diff --git a/src/PhpPresentation/AbstractShape.php b/src/PhpPresentation/AbstractShape.php
index c73060f29..2015d0451 100644
--- a/src/PhpPresentation/AbstractShape.php
+++ b/src/PhpPresentation/AbstractShape.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use PhpOffice\PhpPresentation\Shape\Hyperlink;
diff --git a/src/PhpPresentation/Autoloader.php b/src/PhpPresentation/Autoloader.php
index 02d112c13..6c7211fde 100644
--- a/src/PhpPresentation/Autoloader.php
+++ b/src/PhpPresentation/Autoloader.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 /**
@@ -43,6 +45,9 @@ public static function autoload(string $class): void
         if (0 === strncmp(self::NAMESPACE_PREFIX, $class, $prefixLength)) {
             $file = str_replace('\\', DIRECTORY_SEPARATOR, substr($class, $prefixLength));
             $file = realpath(__DIR__ . (empty($file) ? '' : DIRECTORY_SEPARATOR) . $file . '.php');
+            if (!$file) {
+                return;
+            }
             if (file_exists($file)) {
                 /** @noinspection PhpIncludeInspection Dynamic includes */
                 require_once $file;
diff --git a/src/PhpPresentation/ComparableInterface.php b/src/PhpPresentation/ComparableInterface.php
index d4dbe569b..7fefbda1c 100644
--- a/src/PhpPresentation/ComparableInterface.php
+++ b/src/PhpPresentation/ComparableInterface.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 /**
diff --git a/src/PhpPresentation/DocumentLayout.php b/src/PhpPresentation/DocumentLayout.php
index b5ef68a2c..bf7910407 100644
--- a/src/PhpPresentation/DocumentLayout.php
+++ b/src/PhpPresentation/DocumentLayout.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use PhpOffice\Common\Drawing;
@@ -224,7 +226,7 @@ protected function convertUnit(float $value, string $fromUnit, string $toUnit):
                 $value /= 914400;
                 break;
             case self::UNIT_PIXEL:
-                $value = Drawing::emuToPixels($value);
+                $value = Drawing::emuToPixels((int) $value);
                 break;
             case self::UNIT_POINT:
                 $value /= 12700;
diff --git a/src/PhpPresentation/DocumentProperties.php b/src/PhpPresentation/DocumentProperties.php
index 85fb89442..ab4542043 100644
--- a/src/PhpPresentation/DocumentProperties.php
+++ b/src/PhpPresentation/DocumentProperties.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 /**
@@ -398,9 +400,9 @@ public function isCustomPropertySet(string $propertyName): bool
      *
      * @param string $propertyName
      *
-     * @return string|null
+     * @return mixed|null
      */
-    public function getCustomPropertyValue(string $propertyName): ?string
+    public function getCustomPropertyValue(string $propertyName)
     {
         if ($this->isCustomPropertySet($propertyName)) {
             return $this->customProperties[$propertyName]['value'];
diff --git a/src/PhpPresentation/GeometryCalculator.php b/src/PhpPresentation/GeometryCalculator.php
index 8d309bf8d..7eccbf895 100644
--- a/src/PhpPresentation/GeometryCalculator.php
+++ b/src/PhpPresentation/GeometryCalculator.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 /**
diff --git a/src/PhpPresentation/HashTable.php b/src/PhpPresentation/HashTable.php
index 59b95c67c..242b582a7 100644
--- a/src/PhpPresentation/HashTable.php
+++ b/src/PhpPresentation/HashTable.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 /**
diff --git a/src/PhpPresentation/IOFactory.php b/src/PhpPresentation/IOFactory.php
index b29df5b14..5a34cd171 100644
--- a/src/PhpPresentation/IOFactory.php
+++ b/src/PhpPresentation/IOFactory.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use PhpOffice\PhpPresentation\Reader\ReaderInterface;
@@ -51,7 +53,7 @@ public static function createWriter(PhpPresentation $phpPresentation, string $na
      *
      * @throws \Exception
      */
-    public static function createReader(string $name = ''): ReaderInterface
+    public static function createReader(string $name): ReaderInterface
     {
         $class = 'PhpOffice\\PhpPresentation\\Reader\\' . $name;
 
diff --git a/src/PhpPresentation/PhpPresentation.php b/src/PhpPresentation/PhpPresentation.php
index 91adcb8c3..4e3c4665d 100644
--- a/src/PhpPresentation/PhpPresentation.php
+++ b/src/PhpPresentation/PhpPresentation.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use ArrayObject;
diff --git a/src/PhpPresentation/PresentationProperties.php b/src/PhpPresentation/PresentationProperties.php
index 8a76d887a..a8ee8eff3 100644
--- a/src/PhpPresentation/PresentationProperties.php
+++ b/src/PhpPresentation/PresentationProperties.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 class PresentationProperties
diff --git a/src/PhpPresentation/Reader/ODPresentation.php b/src/PhpPresentation/Reader/ODPresentation.php
index a9578b541..0ba6288c4 100644
--- a/src/PhpPresentation/Reader/ODPresentation.php
+++ b/src/PhpPresentation/Reader/ODPresentation.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Reader;
 
 use DateTime;
diff --git a/src/PhpPresentation/Reader/PowerPoint2007.php b/src/PhpPresentation/Reader/PowerPoint2007.php
index c7b62a0b1..3b19e7cb6 100644
--- a/src/PhpPresentation/Reader/PowerPoint2007.php
+++ b/src/PhpPresentation/Reader/PowerPoint2007.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Reader;
 
 use DateTime;
@@ -540,24 +542,25 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
                     } else {
                         $level = str_replace('a:lvl', '', $oElementLvl->nodeName);
                         $level = str_replace('pPr', '', $level);
+                        $level = intval($level);
                     }
 
                     if ($oElementLvl->hasAttribute('algn')) {
                         $oRTParagraph->getAlignment()->setHorizontal($oElementLvl->getAttribute('algn'));
                     }
                     if ($oElementLvl->hasAttribute('marL')) {
-                        $val = $oElementLvl->getAttribute('marL');
-                        $val = CommonDrawing::emuToPixels($val);
+                        $val = (int) $oElementLvl->getAttribute('marL');
+                        $val = CommonDrawing::emuToPixels((int) $val);
                         $oRTParagraph->getAlignment()->setMarginLeft($val);
                     }
                     if ($oElementLvl->hasAttribute('marR')) {
-                        $val = $oElementLvl->getAttribute('marR');
-                        $val = CommonDrawing::emuToPixels($val);
+                        $val = (int) $oElementLvl->getAttribute('marR');
+                        $val = CommonDrawing::emuToPixels((int) $val);
                         $oRTParagraph->getAlignment()->setMarginRight($val);
                     }
                     if ($oElementLvl->hasAttribute('indent')) {
-                        $val = $oElementLvl->getAttribute('indent');
-                        $val = CommonDrawing::emuToPixels($val);
+                        $val = (int) $oElementLvl->getAttribute('indent');
+                        $val = CommonDrawing::emuToPixels((int) $val);
                         $oRTParagraph->getAlignment()->setIndent($val);
                     }
                     $oElementLvlDefRPR = $xmlReader->getElement('a:defRPr', $oElementLvl);
@@ -840,27 +843,27 @@ protected function loadShapeDrawing(XMLReader $document, DOMElement $node, Abstr
         $oElement = $document->getElement('p:spPr/a:xfrm', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('rot')) {
-                $oShape->setRotation((int) CommonDrawing::angleToDegrees($oElement->getAttribute('rot')));
+                $oShape->setRotation((int) CommonDrawing::angleToDegrees((int) $oElement->getAttribute('rot')));
             }
         }
 
         $oElement = $document->getElement('p:spPr/a:xfrm/a:off', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('x')) {
-                $oShape->setOffsetX(CommonDrawing::emuToPixels($oElement->getAttribute('x')));
+                $oShape->setOffsetX(CommonDrawing::emuToPixels((int) $oElement->getAttribute('x')));
             }
             if ($oElement->hasAttribute('y')) {
-                $oShape->setOffsetY(CommonDrawing::emuToPixels($oElement->getAttribute('y')));
+                $oShape->setOffsetY(CommonDrawing::emuToPixels((int) $oElement->getAttribute('y')));
             }
         }
 
         $oElement = $document->getElement('p:spPr/a:xfrm/a:ext', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('cx')) {
-                $oShape->setWidth(CommonDrawing::emuToPixels($oElement->getAttribute('cx')));
+                $oShape->setWidth(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cx')));
             }
             if ($oElement->hasAttribute('cy')) {
-                $oShape->setHeight(CommonDrawing::emuToPixels($oElement->getAttribute('cy')));
+                $oShape->setHeight(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cy')));
             }
         }
 
@@ -871,13 +874,13 @@ protected function loadShapeDrawing(XMLReader $document, DOMElement $node, Abstr
             $oSubElement = $document->getElement('a:outerShdw', $oElement);
             if ($oSubElement instanceof DOMElement) {
                 if ($oSubElement->hasAttribute('blurRad')) {
-                    $oShape->getShadow()->setBlurRadius(CommonDrawing::emuToPixels($oSubElement->getAttribute('blurRad')));
+                    $oShape->getShadow()->setBlurRadius(CommonDrawing::emuToPixels((int) $oSubElement->getAttribute('blurRad')));
                 }
                 if ($oSubElement->hasAttribute('dist')) {
-                    $oShape->getShadow()->setDistance(CommonDrawing::emuToPixels($oSubElement->getAttribute('dist')));
+                    $oShape->getShadow()->setDistance(CommonDrawing::emuToPixels((int) $oSubElement->getAttribute('dist')));
                 }
                 if ($oSubElement->hasAttribute('dir')) {
-                    $oShape->getShadow()->setDirection((int) CommonDrawing::angleToDegrees($oSubElement->getAttribute('dir')));
+                    $oShape->getShadow()->setDirection((int) CommonDrawing::angleToDegrees((int) $oSubElement->getAttribute('dir')));
                 }
                 if ($oSubElement->hasAttribute('algn')) {
                     $oShape->getShadow()->setAlignment($oSubElement->getAttribute('algn'));
@@ -922,26 +925,26 @@ protected function loadShapeRichText(XMLReader $document, DOMElement $node, Abst
 
         $oElement = $document->getElement('p:spPr/a:xfrm', $node);
         if ($oElement instanceof DOMElement && $oElement->hasAttribute('rot')) {
-            $oShape->setRotation((int) CommonDrawing::angleToDegrees($oElement->getAttribute('rot')));
+            $oShape->setRotation((int) CommonDrawing::angleToDegrees((int) $oElement->getAttribute('rot')));
         }
 
         $oElement = $document->getElement('p:spPr/a:xfrm/a:off', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('x')) {
-                $oShape->setOffsetX(CommonDrawing::emuToPixels($oElement->getAttribute('x')));
+                $oShape->setOffsetX(CommonDrawing::emuToPixels((int) $oElement->getAttribute('x')));
             }
             if ($oElement->hasAttribute('y')) {
-                $oShape->setOffsetY(CommonDrawing::emuToPixels($oElement->getAttribute('y')));
+                $oShape->setOffsetY(CommonDrawing::emuToPixels((int) $oElement->getAttribute('y')));
             }
         }
 
         $oElement = $document->getElement('p:spPr/a:xfrm/a:ext', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('cx')) {
-                $oShape->setWidth(CommonDrawing::emuToPixels($oElement->getAttribute('cx')));
+                $oShape->setWidth(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cx')));
             }
             if ($oElement->hasAttribute('cy')) {
-                $oShape->setHeight(CommonDrawing::emuToPixels($oElement->getAttribute('cy')));
+                $oShape->setHeight(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cy')));
             }
         }
 
@@ -987,20 +990,20 @@ protected function loadShapeTable(XMLReader $document, DOMElement $node, Abstrac
         $oElement = $document->getElement('p:xfrm/a:off', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('x')) {
-                $oShape->setOffsetX(CommonDrawing::emuToPixels($oElement->getAttribute('x')));
+                $oShape->setOffsetX(CommonDrawing::emuToPixels((int) $oElement->getAttribute('x')));
             }
             if ($oElement->hasAttribute('y')) {
-                $oShape->setOffsetY(CommonDrawing::emuToPixels($oElement->getAttribute('y')));
+                $oShape->setOffsetY(CommonDrawing::emuToPixels((int) $oElement->getAttribute('y')));
             }
         }
 
         $oElement = $document->getElement('p:xfrm/a:ext', $node);
         if ($oElement instanceof DOMElement) {
             if ($oElement->hasAttribute('cx')) {
-                $oShape->setWidth(CommonDrawing::emuToPixels($oElement->getAttribute('cx')));
+                $oShape->setWidth(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cx')));
             }
             if ($oElement->hasAttribute('cy')) {
-                $oShape->setHeight(CommonDrawing::emuToPixels($oElement->getAttribute('cy')));
+                $oShape->setHeight(CommonDrawing::emuToPixels((int) $oElement->getAttribute('cy')));
             }
         }
 
@@ -1009,7 +1012,7 @@ protected function loadShapeTable(XMLReader $document, DOMElement $node, Abstrac
         $oShape->createRow();
         foreach ($arrayElements as $key => $oElement) {
             if ($oElement instanceof DOMElement && $oElement->getAttribute('w')) {
-                $oShape->getRow(0)->getCell($key)->setWidth(CommonDrawing::emuToPixels($oElement->getAttribute('w')));
+                $oShape->getRow(0)->getCell($key)->setWidth(CommonDrawing::emuToPixels((int) $oElement->getAttribute('w')));
             }
         }
 
@@ -1023,7 +1026,7 @@ protected function loadShapeTable(XMLReader $document, DOMElement $node, Abstrac
                 $oRow = $oShape->createRow();
             }
             if ($oElementRow->hasAttribute('h')) {
-                $oRow->setHeight(CommonDrawing::emuToPixels($oElementRow->getAttribute('h')));
+                $oRow->setHeight(CommonDrawing::emuToPixels((int) $oElementRow->getAttribute('h')));
             }
             $arrayElementsCell = $document->getElements('a:tc', $oElementRow);
             foreach ($arrayElementsCell as $keyCell => $oElementCell) {
@@ -1125,13 +1128,13 @@ protected function loadParagraph(XMLReader $document, DOMElement $oElement, $oSh
                 $oParagraph->getAlignment()->setVertical($oSubElement->getAttribute('fontAlgn'));
             }
             if ($oSubElement->hasAttribute('marL')) {
-                $oParagraph->getAlignment()->setMarginLeft(CommonDrawing::emuToPixels($oSubElement->getAttribute('marL')));
+                $oParagraph->getAlignment()->setMarginLeft(CommonDrawing::emuToPixels((int) $oSubElement->getAttribute('marL')));
             }
             if ($oSubElement->hasAttribute('marR')) {
-                $oParagraph->getAlignment()->setMarginRight(CommonDrawing::emuToPixels($oSubElement->getAttribute('marR')));
+                $oParagraph->getAlignment()->setMarginRight(CommonDrawing::emuToPixels((int) $oSubElement->getAttribute('marR')));
             }
             if ($oSubElement->hasAttribute('indent')) {
-                $oParagraph->getAlignment()->setIndent(CommonDrawing::emuToPixels($oSubElement->getAttribute('indent')));
+                $oParagraph->getAlignment()->setIndent(CommonDrawing::emuToPixels((int) $oSubElement->getAttribute('indent')));
             }
             if ($oSubElement->hasAttribute('lvl')) {
                 $oParagraph->getAlignment()->setLevel((int) $oSubElement->getAttribute('lvl'));
@@ -1339,7 +1342,7 @@ protected function loadStyleFill(XMLReader $xmlReader, DOMElement $oElement): ?F
 
             $oRotation = $xmlReader->getElement('a:lin', $oElementFill);
             if ($oRotation instanceof DOMElement && $oRotation->hasAttribute('ang')) {
-                $oFill->setRotation(CommonDrawing::angleToDegrees($oRotation->getAttribute('ang')));
+                $oFill->setRotation(CommonDrawing::angleToDegrees((int) $oRotation->getAttribute('ang')));
             }
 
             return $oFill;
diff --git a/src/PhpPresentation/Reader/PowerPoint97.php b/src/PhpPresentation/Reader/PowerPoint97.php
index 18251cc75..9c086f69f 100644
--- a/src/PhpPresentation/Reader/PowerPoint97.php
+++ b/src/PhpPresentation/Reader/PowerPoint97.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Reader;
 
 use PhpOffice\Common\Microsoft\OLERead;
@@ -31,6 +33,7 @@
 use PhpOffice\PhpPresentation\Style\Alignment;
 use PhpOffice\PhpPresentation\Style\Bullet;
 use PhpOffice\PhpPresentation\Style\Color;
+use PhpOffice\PhpPresentation\Style\Font;
 
 /**
  * Serialized format reader.
@@ -1654,7 +1657,9 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
                             $txtRun->getFont()->setItalic($clientTextbox['part' . $inc]['italic']);
                         }
                         if (isset($clientTextbox['part' . $inc]['underline'])) {
-                            $txtRun->getFont()->setUnderline($clientTextbox['part' . $inc]['underline']);
+                            $txtRun->getFont()->setUnderline(
+                                $clientTextbox['part' . $inc]['underline'] ? Font::UNDERLINE_SINGLE : Font::UNDERLINE_NONE
+                            );
                         }
                         if (isset($clientTextbox['part' . $inc]['fontName'])) {
                             $txtRun->getFont()->setName($clientTextbox['part' . $inc]['fontName']);
@@ -1953,7 +1958,7 @@ private function readRecordOfficeArtFDG(string $stream, int $pos): array
     /**
      * The OfficeArtFOPT record specifies a table of OfficeArtRGFOPTE records.
      *
-     * @return array<string, int>
+     * @return array<string, int|string|bool>
      *
      * @see https://msdn.microsoft.com/en-us/library/dd943404(v=office.12).aspx
      */
@@ -2004,22 +2009,22 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                     case 0x0081:
                         // Text : dxTextLeft
                         //@link : http://msdn.microsoft.com/en-us/library/dd953234(v=office.12).aspx
-                        $arrayReturn['insetLeft'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['insetLeft'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x0082:
                         // Text : dyTextTop
                         //@link : http://msdn.microsoft.com/en-us/library/dd925068(v=office.12).aspx
-                        $arrayReturn['insetTop'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['insetTop'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x0083:
                         // Text : dxTextRight
                         //@link : http://msdn.microsoft.com/en-us/library/dd906782(v=office.12).aspx
-                        $arrayReturn['insetRight'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['insetRight'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x0084:
                         // Text : dyTextBottom
                         //@link : http://msdn.microsoft.com/en-us/library/dd772858(v=office.12).aspx
-                        $arrayReturn['insetBottom'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['insetBottom'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x0085:
                         // Text : WrapText
@@ -2139,12 +2144,12 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                     case 0x0193:
                         // Fill : fillRectRight
                         //@link : http://msdn.microsoft.com/en-us/library/dd951294(v=office.12).aspx
-                        // echo 'fillRectRight  : '.\PhpOffice\Common\Drawing::emuToPixels($opt['op']).EOL;
+                        // echo 'fillRectRight  : '.\PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']).EOL;
                         break;
                     case 0x0194:
                         // Fill : fillRectBottom
                         //@link : http://msdn.microsoft.com/en-us/library/dd910194(v=office.12).aspx
-                        // echo 'fillRectBottom   : '.\PhpOffice\Common\Drawing::emuToPixels($opt['op']).EOL;
+                        // echo 'fillRectBottom   : '.\PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']).EOL;
                         break;
                     case 0x01BF:
                         // Fill : Fill Style Boolean Properties
@@ -2170,7 +2175,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                     case 0x01CB:
                         // Line Style : lineWidth
                         //@link : http://msdn.microsoft.com/en-us/library/dd926964(v=office.12).aspx
-                        $arrayReturn['lineWidth'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['lineWidth'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x01D6:
                         // Line Style : lineJoinStyle
@@ -2195,12 +2200,12 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                     case 0x0205:
                         // Shadow Style : shadowOffsetX
                         //@link : http://msdn.microsoft.com/en-us/library/dd945280(v=office.12).aspx
-                        $arrayReturn['shadowOffsetX'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['shadowOffsetX'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x0206:
                         // Shadow Style : shadowOffsetY
                         //@link : http://msdn.microsoft.com/en-us/library/dd907855(v=office.12).aspx
-                        $arrayReturn['shadowOffsetY'] = \PhpOffice\Common\Drawing::emuToPixels($opt['op']);
+                        $arrayReturn['shadowOffsetY'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
                         break;
                     case 0x023F:
                         // Shadow Style : Shadow Style Boolean Properties
diff --git a/src/PhpPresentation/Reader/ReaderInterface.php b/src/PhpPresentation/Reader/ReaderInterface.php
index 5966da33b..41bc7c34f 100644
--- a/src/PhpPresentation/Reader/ReaderInterface.php
+++ b/src/PhpPresentation/Reader/ReaderInterface.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Reader;
 
 use PhpOffice\PhpPresentation\PhpPresentation;
diff --git a/src/PhpPresentation/Reader/Serialized.php b/src/PhpPresentation/Reader/Serialized.php
index 30d4320b0..f0cb9fe6b 100644
--- a/src/PhpPresentation/Reader/Serialized.php
+++ b/src/PhpPresentation/Reader/Serialized.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Reader;
 
 use Exception;
diff --git a/src/PhpPresentation/Shape/AbstractGraphic.php b/src/PhpPresentation/Shape/AbstractGraphic.php
index 0192e1a93..e7a4e731d 100644
--- a/src/PhpPresentation/Shape/AbstractGraphic.php
+++ b/src/PhpPresentation/Shape/AbstractGraphic.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/src/PhpPresentation/Shape/AutoShape.php b/src/PhpPresentation/Shape/AutoShape.php
index e69b4c0f4..3d2c21ca5 100644
--- a/src/PhpPresentation/Shape/AutoShape.php
+++ b/src/PhpPresentation/Shape/AutoShape.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/src/PhpPresentation/Shape/Chart.php b/src/PhpPresentation/Shape/Chart.php
index 7cebcb3b2..3d56b7378 100644
--- a/src/PhpPresentation/Shape/Chart.php
+++ b/src/PhpPresentation/Shape/Chart.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Axis.php b/src/PhpPresentation/Shape/Chart/Axis.php
index bc0d88d6b..e82a85eb0 100644
--- a/src/PhpPresentation/Shape/Chart/Axis.php
+++ b/src/PhpPresentation/Shape/Chart/Axis.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Gridlines.php b/src/PhpPresentation/Shape/Chart/Gridlines.php
index bf41d442d..83f124886 100644
--- a/src/PhpPresentation/Shape/Chart/Gridlines.php
+++ b/src/PhpPresentation/Shape/Chart/Gridlines.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
diff --git a/src/PhpPresentation/Shape/Chart/Legend.php b/src/PhpPresentation/Shape/Chart/Legend.php
index 33bd590ea..0a7a51131 100644
--- a/src/PhpPresentation/Shape/Chart/Legend.php
+++ b/src/PhpPresentation/Shape/Chart/Legend.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Marker.php b/src/PhpPresentation/Shape/Chart/Marker.php
index f6090a43c..008f787b3 100644
--- a/src/PhpPresentation/Shape/Chart/Marker.php
+++ b/src/PhpPresentation/Shape/Chart/Marker.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Style\Border;
diff --git a/src/PhpPresentation/Shape/Chart/PlotArea.php b/src/PhpPresentation/Shape/Chart/PlotArea.php
index f5d21de1d..f20a290c2 100644
--- a/src/PhpPresentation/Shape/Chart/PlotArea.php
+++ b/src/PhpPresentation/Shape/Chart/PlotArea.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Series.php b/src/PhpPresentation/Shape/Chart/Series.php
index b60d03f24..ea1bf4996 100644
--- a/src/PhpPresentation/Shape/Chart/Series.php
+++ b/src/PhpPresentation/Shape/Chart/Series.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Title.php b/src/PhpPresentation/Shape/Chart/Title.php
index f8ebd144e..ceef81b00 100644
--- a/src/PhpPresentation/Shape/Chart/Title.php
+++ b/src/PhpPresentation/Shape/Chart/Title.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractType.php b/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
index 99b42c430..112123115 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
index 600bf7391..234717698 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 /**
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
index 32c5e7f0e..3040f0bc3 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 class AbstractTypeLine extends AbstractType
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
index 08d40b3ce..b538d9a16 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 /**
diff --git a/src/PhpPresentation/Shape/Chart/Type/Area.php b/src/PhpPresentation/Shape/Chart/Type/Area.php
index a8c39ff00..49fc9bd6b 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Area.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Area.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Bar.php b/src/PhpPresentation/Shape/Chart/Type/Bar.php
index 602b69d53..9ea5b3dc7 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Bar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Bar.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Bar3D.php b/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
index b2127862d..1011ad071 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Doughnut.php b/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
index 33da681fd..292c82326 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Line.php b/src/PhpPresentation/Shape/Chart/Type/Line.php
index 4d1f07cad..cefca9ddd 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Line.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Line.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Pie.php b/src/PhpPresentation/Shape/Chart/Type/Pie.php
index 94c9ff20b..53cb6b1fe 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Pie.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Pie.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Pie3D.php b/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
index 1ee43bce9..05689c61a 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Radar.php b/src/PhpPresentation/Shape/Chart/Type/Radar.php
index 85525f10e..9f45b5d5e 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Radar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Radar.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/Type/Scatter.php b/src/PhpPresentation/Shape/Chart/Type/Scatter.php
index 3cb2bba43..58f2576e7 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Scatter.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Scatter.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Chart/View3D.php b/src/PhpPresentation/Shape/Chart/View3D.php
index f358db059..21bbaeefe 100644
--- a/src/PhpPresentation/Shape/Chart/View3D.php
+++ b/src/PhpPresentation/Shape/Chart/View3D.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Chart;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Comment.php b/src/PhpPresentation/Shape/Comment.php
index 4fa5e86a7..d909e0548 100644
--- a/src/PhpPresentation/Shape/Comment.php
+++ b/src/PhpPresentation/Shape/Comment.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/src/PhpPresentation/Shape/Comment/Author.php b/src/PhpPresentation/Shape/Comment/Author.php
index 7bbe86b6a..59784f3e9 100644
--- a/src/PhpPresentation/Shape/Comment/Author.php
+++ b/src/PhpPresentation/Shape/Comment/Author.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Comment;
 
diff --git a/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php b/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
index 80108f7c6..f361ba7d4 100644
--- a/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
+++ b/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Drawing;
 
diff --git a/src/PhpPresentation/Shape/Drawing/Base64.php b/src/PhpPresentation/Shape/Drawing/Base64.php
index 0a051e81c..889bc73e3 100644
--- a/src/PhpPresentation/Shape/Drawing/Base64.php
+++ b/src/PhpPresentation/Shape/Drawing/Base64.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Drawing;
 
diff --git a/src/PhpPresentation/Shape/Drawing/File.php b/src/PhpPresentation/Shape/Drawing/File.php
index 41f93dac6..3f8eceefc 100644
--- a/src/PhpPresentation/Shape/Drawing/File.php
+++ b/src/PhpPresentation/Shape/Drawing/File.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Drawing;
 
diff --git a/src/PhpPresentation/Shape/Drawing/Gd.php b/src/PhpPresentation/Shape/Drawing/Gd.php
index 542127d5d..59bcf8d3d 100644
--- a/src/PhpPresentation/Shape/Drawing/Gd.php
+++ b/src/PhpPresentation/Shape/Drawing/Gd.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Drawing;
 
diff --git a/src/PhpPresentation/Shape/Drawing/ZipFile.php b/src/PhpPresentation/Shape/Drawing/ZipFile.php
index 119980460..e14573011 100644
--- a/src/PhpPresentation/Shape/Drawing/ZipFile.php
+++ b/src/PhpPresentation/Shape/Drawing/ZipFile.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Shape\Drawing;
 
diff --git a/src/PhpPresentation/Shape/Group.php b/src/PhpPresentation/Shape/Group.php
index 361b2be57..537e33763 100644
--- a/src/PhpPresentation/Shape/Group.php
+++ b/src/PhpPresentation/Shape/Group.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use ArrayObject;
diff --git a/src/PhpPresentation/Shape/Hyperlink.php b/src/PhpPresentation/Shape/Hyperlink.php
index a7aac436e..7063c726c 100644
--- a/src/PhpPresentation/Shape/Hyperlink.php
+++ b/src/PhpPresentation/Shape/Hyperlink.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 /**
diff --git a/src/PhpPresentation/Shape/Line.php b/src/PhpPresentation/Shape/Line.php
index 5ae89e36c..be7574d55 100644
--- a/src/PhpPresentation/Shape/Line.php
+++ b/src/PhpPresentation/Shape/Line.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/src/PhpPresentation/Shape/Media.php b/src/PhpPresentation/Shape/Media.php
index f70ba689b..1207195d5 100644
--- a/src/PhpPresentation/Shape/Media.php
+++ b/src/PhpPresentation/Shape/Media.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Placeholder.php b/src/PhpPresentation/Shape/Placeholder.php
index b777547e8..45f6ac820 100644
--- a/src/PhpPresentation/Shape/Placeholder.php
+++ b/src/PhpPresentation/Shape/Placeholder.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 class Placeholder
diff --git a/src/PhpPresentation/Shape/RichText.php b/src/PhpPresentation/Shape/RichText.php
index 5bd118ee6..89b62acc2 100644
--- a/src/PhpPresentation/Shape/RichText.php
+++ b/src/PhpPresentation/Shape/RichText.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/src/PhpPresentation/Shape/RichText/BreakElement.php b/src/PhpPresentation/Shape/RichText/BreakElement.php
index 65542411d..5df5f0648 100644
--- a/src/PhpPresentation/Shape/RichText/BreakElement.php
+++ b/src/PhpPresentation/Shape/RichText/BreakElement.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Style\Font;
diff --git a/src/PhpPresentation/Shape/RichText/Paragraph.php b/src/PhpPresentation/Shape/RichText/Paragraph.php
index 939d9d874..cadeaa17c 100644
--- a/src/PhpPresentation/Shape/RichText/Paragraph.php
+++ b/src/PhpPresentation/Shape/RichText/Paragraph.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\RichText;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/RichText/Run.php b/src/PhpPresentation/Shape/RichText/Run.php
index 4e444a4b3..c4fabf545 100644
--- a/src/PhpPresentation/Shape/RichText/Run.php
+++ b/src/PhpPresentation/Shape/RichText/Run.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Style\Font;
diff --git a/src/PhpPresentation/Shape/RichText/TextElement.php b/src/PhpPresentation/Shape/RichText/TextElement.php
index 2be9ab4c0..5efee1157 100644
--- a/src/PhpPresentation/Shape/RichText/TextElement.php
+++ b/src/PhpPresentation/Shape/RichText/TextElement.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Shape\Hyperlink;
diff --git a/src/PhpPresentation/Shape/RichText/TextElementInterface.php b/src/PhpPresentation/Shape/RichText/TextElementInterface.php
index c3f553d16..4c704436c 100644
--- a/src/PhpPresentation/Shape/RichText/TextElementInterface.php
+++ b/src/PhpPresentation/Shape/RichText/TextElementInterface.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\RichText;
 
 /**
diff --git a/src/PhpPresentation/Shape/Table.php b/src/PhpPresentation/Shape/Table.php
index 2fab8177f..6df8edff0 100644
--- a/src/PhpPresentation/Shape/Table.php
+++ b/src/PhpPresentation/Shape/Table.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Table/Cell.php b/src/PhpPresentation/Shape/Table/Cell.php
index 521e4e676..4231c5aa1 100644
--- a/src/PhpPresentation/Shape/Table/Cell.php
+++ b/src/PhpPresentation/Shape/Table/Cell.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Table;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Shape/Table/Row.php b/src/PhpPresentation/Shape/Table/Row.php
index 576533700..3e8c9cb51 100644
--- a/src/PhpPresentation/Shape/Table/Row.php
+++ b/src/PhpPresentation/Shape/Table/Row.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Shape\Table;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/ShapeContainerInterface.php b/src/PhpPresentation/ShapeContainerInterface.php
index aef612571..48e24f167 100644
--- a/src/PhpPresentation/ShapeContainerInterface.php
+++ b/src/PhpPresentation/ShapeContainerInterface.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use ArrayObject;
diff --git a/src/PhpPresentation/Slide.php b/src/PhpPresentation/Slide.php
index fbbe4ecb2..61c0d5775 100644
--- a/src/PhpPresentation/Slide.php
+++ b/src/PhpPresentation/Slide.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation;
 
 use PhpOffice\PhpPresentation\Slide\AbstractSlide;
diff --git a/src/PhpPresentation/Slide/AbstractBackground.php b/src/PhpPresentation/Slide/AbstractBackground.php
index d5b34356f..42aa4d585 100644
--- a/src/PhpPresentation/Slide/AbstractBackground.php
+++ b/src/PhpPresentation/Slide/AbstractBackground.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Slide;
 
diff --git a/src/PhpPresentation/Slide/AbstractSlide.php b/src/PhpPresentation/Slide/AbstractSlide.php
index 2ac59bbc8..d633ea99d 100644
--- a/src/PhpPresentation/Slide/AbstractSlide.php
+++ b/src/PhpPresentation/Slide/AbstractSlide.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 use ArrayObject;
diff --git a/src/PhpPresentation/Slide/Animation.php b/src/PhpPresentation/Slide/Animation.php
index e17d37b4d..2e6d1dc48 100644
--- a/src/PhpPresentation/Slide/Animation.php
+++ b/src/PhpPresentation/Slide/Animation.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Slide;
 
diff --git a/src/PhpPresentation/Slide/Background/Color.php b/src/PhpPresentation/Slide/Background/Color.php
index 0dc1c51bf..24507d8dc 100644
--- a/src/PhpPresentation/Slide/Background/Color.php
+++ b/src/PhpPresentation/Slide/Background/Color.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Slide\Background;
 
diff --git a/src/PhpPresentation/Slide/Background/Image.php b/src/PhpPresentation/Slide/Background/Image.php
index 3f8181e8c..2a10d6565 100644
--- a/src/PhpPresentation/Slide/Background/Image.php
+++ b/src/PhpPresentation/Slide/Background/Image.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Slide\Background;
 
@@ -70,9 +88,9 @@ public function setPath(string $pValue = '', bool $pVerifyFile = true)
      *
      * @return string
      */
-    public function getFilename()
+    public function getFilename(): string
     {
-        return basename($this->path);
+        return $this->path ? basename($this->path) : '';
     }
 
     /**
@@ -82,7 +100,7 @@ public function getFilename()
      */
     public function getExtension(): string
     {
-        $exploded = explode('.', basename($this->path));
+        $exploded = explode('.', $this->getFilename());
 
         return $exploded[count($exploded) - 1];
     }
diff --git a/src/PhpPresentation/Slide/Background/SchemeColor.php b/src/PhpPresentation/Slide/Background/SchemeColor.php
index bd063b3a6..3cb785df5 100644
--- a/src/PhpPresentation/Slide/Background/SchemeColor.php
+++ b/src/PhpPresentation/Slide/Background/SchemeColor.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Slide\Background;
 
diff --git a/src/PhpPresentation/Slide/Iterator.php b/src/PhpPresentation/Slide/Iterator.php
index 73f3e0bb7..0164d655e 100644
--- a/src/PhpPresentation/Slide/Iterator.php
+++ b/src/PhpPresentation/Slide/Iterator.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 use IteratorIterator;
diff --git a/src/PhpPresentation/Slide/Layout.php b/src/PhpPresentation/Slide/Layout.php
index f7204bfb4..1c1ec93cb 100644
--- a/src/PhpPresentation/Slide/Layout.php
+++ b/src/PhpPresentation/Slide/Layout.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 /**
diff --git a/src/PhpPresentation/Slide/Note.php b/src/PhpPresentation/Slide/Note.php
index e1a5810b5..f8bc8b831 100644
--- a/src/PhpPresentation/Slide/Note.php
+++ b/src/PhpPresentation/Slide/Note.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 use ArrayObject;
diff --git a/src/PhpPresentation/Slide/SlideLayout.php b/src/PhpPresentation/Slide/SlideLayout.php
index f73e17a34..9c30db23b 100644
--- a/src/PhpPresentation/Slide/SlideLayout.php
+++ b/src/PhpPresentation/Slide/SlideLayout.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Slide/SlideMaster.php b/src/PhpPresentation/Slide/SlideMaster.php
index 493eb8e74..13e42aed9 100644
--- a/src/PhpPresentation/Slide/SlideMaster.php
+++ b/src/PhpPresentation/Slide/SlideMaster.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Slide/Transition.php b/src/PhpPresentation/Slide/Transition.php
index 99d340b76..9836f7c62 100644
--- a/src/PhpPresentation/Slide/Transition.php
+++ b/src/PhpPresentation/Slide/Transition.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Slide;
 
 /**
diff --git a/src/PhpPresentation/Style/Alignment.php b/src/PhpPresentation/Style/Alignment.php
index cf0c92202..e620626bd 100644
--- a/src/PhpPresentation/Style/Alignment.php
+++ b/src/PhpPresentation/Style/Alignment.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Border.php b/src/PhpPresentation/Style/Border.php
index 4432dc077..da8c6b60a 100644
--- a/src/PhpPresentation/Style/Border.php
+++ b/src/PhpPresentation/Style/Border.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Borders.php b/src/PhpPresentation/Style/Borders.php
index a23bc88c0..01fa0112a 100644
--- a/src/PhpPresentation/Style/Borders.php
+++ b/src/PhpPresentation/Style/Borders.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Bullet.php b/src/PhpPresentation/Style/Bullet.php
index 64313d734..dd3729d5d 100644
--- a/src/PhpPresentation/Style/Bullet.php
+++ b/src/PhpPresentation/Style/Bullet.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Color.php b/src/PhpPresentation/Style/Color.php
index 18e652614..56e51029f 100644
--- a/src/PhpPresentation/Style/Color.php
+++ b/src/PhpPresentation/Style/Color.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
@@ -95,12 +97,12 @@ public function setARGB($pValue = self::COLOR_BLACK)
      *
      * @return int
      */
-    public function getAlpha()
+    public function getAlpha(): int
     {
         $alpha = 100;
         if (strlen($this->argb) >= 6) {
             $dec = hexdec(substr($this->argb, 0, 2));
-            $alpha = number_format(($dec / 255) * 100, 2);
+            $alpha = (int) number_format(($dec / 255) * 100, 0);
         }
 
         return $alpha;
@@ -113,7 +115,7 @@ public function getAlpha()
      *
      * @return $this
      */
-    public function setAlpha($alpha = 100)
+    public function setAlpha(int $alpha = 100): self
     {
         if ($alpha < 0) {
             $alpha = 0;
diff --git a/src/PhpPresentation/Style/ColorMap.php b/src/PhpPresentation/Style/ColorMap.php
index 12fbc81fa..f95a3bc55 100644
--- a/src/PhpPresentation/Style/ColorMap.php
+++ b/src/PhpPresentation/Style/ColorMap.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 /**
diff --git a/src/PhpPresentation/Style/Fill.php b/src/PhpPresentation/Style/Fill.php
index dc1e18d68..cfb13a2f6 100644
--- a/src/PhpPresentation/Style/Fill.php
+++ b/src/PhpPresentation/Style/Fill.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Font.php b/src/PhpPresentation/Style/Font.php
index 87b841c22..2e25b257a 100644
--- a/src/PhpPresentation/Style/Font.php
+++ b/src/PhpPresentation/Style/Font.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/Outline.php b/src/PhpPresentation/Style/Outline.php
index 69e598ec9..99714e27d 100644
--- a/src/PhpPresentation/Style/Outline.php
+++ b/src/PhpPresentation/Style/Outline.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 /**
diff --git a/src/PhpPresentation/Style/SchemeColor.php b/src/PhpPresentation/Style/SchemeColor.php
index f170a71bb..040e103b1 100644
--- a/src/PhpPresentation/Style/SchemeColor.php
+++ b/src/PhpPresentation/Style/SchemeColor.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 class SchemeColor extends Color
diff --git a/src/PhpPresentation/Style/Shadow.php b/src/PhpPresentation/Style/Shadow.php
index a1575bff3..826dd47d9 100644
--- a/src/PhpPresentation/Style/Shadow.php
+++ b/src/PhpPresentation/Style/Shadow.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\ComparableInterface;
diff --git a/src/PhpPresentation/Style/TextStyle.php b/src/PhpPresentation/Style/TextStyle.php
index d18b1f2ee..0670f7645 100644
--- a/src/PhpPresentation/Style/TextStyle.php
+++ b/src/PhpPresentation/Style/TextStyle.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Style;
 
 use PhpOffice\PhpPresentation\Shape\RichText\Paragraph as RichTextParagraph;
diff --git a/src/PhpPresentation/Writer/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
index 4791f3c80..e77b00e28 100644
--- a/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer;
 
diff --git a/src/PhpPresentation/Writer/AbstractWriter.php b/src/PhpPresentation/Writer/AbstractWriter.php
index f7e9ccefa..0646a3a23 100644
--- a/src/PhpPresentation/Writer/AbstractWriter.php
+++ b/src/PhpPresentation/Writer/AbstractWriter.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer;
 
diff --git a/src/PhpPresentation/Writer/ODPresentation.php b/src/PhpPresentation/Writer/ODPresentation.php
index 0c45098cb..bf23d02c8 100644
--- a/src/PhpPresentation/Writer/ODPresentation.php
+++ b/src/PhpPresentation/Writer/ODPresentation.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer;
 
 use DirectoryIterator;
diff --git a/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
index 02a88f4ae..7683106b6 100644
--- a/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
diff --git a/src/PhpPresentation/Writer/ODPresentation/Content.php b/src/PhpPresentation/Writer/ODPresentation/Content.php
index 514538f38..7a29fce45 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Content.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Content.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
@@ -171,11 +189,11 @@ public function writeContent(): string
                         // style:list-level-properties
                         $objWriter->startElement('style:list-level-properties');
                         if ($oAlign->getIndent() < 0) {
-                            $objWriter->writeAttribute('text:space-before', CommonDrawing::pixelsToCentimeters($oAlign->getMarginLeft() - (-1 * $oAlign->getIndent())) . 'cm');
-                            $objWriter->writeAttribute('text:min-label-width', CommonDrawing::pixelsToCentimeters(-1 * $oAlign->getIndent()) . 'cm');
+                            $objWriter->writeAttribute('text:space-before', CommonDrawing::pixelsToCentimeters((int) ($oAlign->getMarginLeft() - (-1 * $oAlign->getIndent()))) . 'cm');
+                            $objWriter->writeAttribute('text:min-label-width', CommonDrawing::pixelsToCentimeters((int) (-1 * $oAlign->getIndent())) . 'cm');
                         } else {
-                            $objWriter->writeAttribute('text:space-before', (CommonDrawing::pixelsToCentimeters($oAlign->getMarginLeft() - $oAlign->getIndent())) . 'cm');
-                            $objWriter->writeAttribute('text:min-label-width', CommonDrawing::pixelsToCentimeters($oAlign->getIndent()) . 'cm');
+                            $objWriter->writeAttribute('text:space-before', (CommonDrawing::pixelsToCentimeters((int) ($oAlign->getMarginLeft() - $oAlign->getIndent()))) . 'cm');
+                            $objWriter->writeAttribute('text:min-label-width', CommonDrawing::pixelsToCentimeters((int) $oAlign->getIndent()) . 'cm');
                         }
 
                         $objWriter->endElement();
@@ -374,10 +392,10 @@ public function writeShapeMedia(XMLWriter $objWriter, Media $shape): void
         // draw:frame
         $objWriter->startElement('draw:frame');
         $objWriter->writeAttribute('draw:name', $shape->getName());
-        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getWidth()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getHeight()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
         $objWriter->writeAttribute('draw:style-name', 'gr' . $this->shapeId);
         // draw:frame > draw:plugin
         $objWriter->startElement('draw:plugin');
@@ -423,10 +441,10 @@ public function writeShapeDrawing(XMLWriter $objWriter, ShapeDrawing\AbstractDra
         // draw:frame
         $objWriter->startElement('draw:frame');
         $objWriter->writeAttribute('draw:name', $shape->getName());
-        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getWidth()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getHeight()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
         $objWriter->writeAttribute('draw:style-name', 'gr' . $this->shapeId);
         // draw:image
         $objWriter->startElement('draw:image');
@@ -470,10 +488,10 @@ public function writeShapeTxt(XMLWriter $objWriter, RichText $shape): void
         // draw:frame
         $objWriter->startElement('draw:frame');
         $objWriter->writeAttribute('draw:style-name', 'gr' . $this->shapeId);
-        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getWidth()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getHeight()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
         // draw:text-box
         $objWriter->startElement('draw:text-box');
 
@@ -629,8 +647,8 @@ public function writeShapeComment(XMLWriter $objWriter, Comment $oShape): void
          */
         // officeooo:annotation
         $objWriter->startElement('officeooo:annotation');
-        $objWriter->writeAttribute('svg:x', number_format(CommonDrawing::pixelsToCentimeters($oShape->getOffsetX()), 2, '.', '') . 'cm');
-        $objWriter->writeAttribute('svg:y', number_format(CommonDrawing::pixelsToCentimeters($oShape->getOffsetY()), 2, '.', '') . 'cm');
+        $objWriter->writeAttribute('svg:x', number_format(CommonDrawing::pixelsToCentimeters((int) $oShape->getOffsetX()), 2, '.', '') . 'cm');
+        $objWriter->writeAttribute('svg:y', number_format(CommonDrawing::pixelsToCentimeters((int) $oShape->getOffsetY()), 2, '.', '') . 'cm');
 
         if ($oShape->getAuthor() instanceof Comment\Author) {
             $objWriter->writeElement('dc:creator', $oShape->getAuthor()->getName());
@@ -647,10 +665,10 @@ public function writeShapeLine(XMLWriter $objWriter, Line $shape): void
         // draw:line
         $objWriter->startElement('draw:line');
         $objWriter->writeAttribute('draw:style-name', 'gr' . $this->shapeId);
-        $objWriter->writeAttribute('svg:x1', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y1', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:x2', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX() + $shape->getWidth()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y2', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY() + $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x1', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y1', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x2', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX() + $shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y2', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY() + $shape->getHeight()), 3) . 'cm');
 
         // text:p
         $objWriter->writeElement('text:p');
@@ -667,10 +685,10 @@ public function writeShapeTable(XMLWriter $objWriter, Table $shape): void
     {
         // draw:frame
         $objWriter->startElement('draw:frame');
-        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getHeight()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getWidth()), 3) . 'cm');
 
         $arrayRows = $shape->getRows();
         if (!empty($arrayRows)) {
@@ -768,10 +786,10 @@ public function writeShapeChart(XMLWriter $objWriter, Chart $shape): void
         // draw:frame
         $objWriter->startElement('draw:frame');
         $objWriter->writeAttribute('draw:name', $shape->getTitle()->getText());
-        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetX()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getOffsetY()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getHeight()), 3) . 'cm');
-        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($shape->getWidth()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetX()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getOffsetY()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getHeight()), 3) . 'cm');
+        $objWriter->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $shape->getWidth()), 3) . 'cm');
 
         // draw:object
         $objWriter->startElement('draw:object');
@@ -1365,7 +1383,7 @@ protected function writeStylePartShadow(XMLWriter $objWriter, Shadow $oShadow):
         $objWriter->writeAttribute('draw:shadow', 'visible');
         $objWriter->writeAttribute('draw:shadow-color', '#' . $oShadow->getColor()->getRGB());
 
-        $distanceCms = CommonDrawing::pixelsToCentimeters($oShadow->getDistance());
+        $distanceCms = CommonDrawing::pixelsToCentimeters((int) $oShadow->getDistance());
         if (0 == $oShadow->getDirection() || 360 == $oShadow->getDirection()) {
             $objWriter->writeAttribute('draw:shadow-offset-x', $distanceCms . 'cm');
             $objWriter->writeAttribute('draw:shadow-offset-y', '0cm');
diff --git a/src/PhpPresentation/Writer/ODPresentation/Meta.php b/src/PhpPresentation/Writer/ODPresentation/Meta.php
index 0afaa895a..b91d7d5d8 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Meta.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Meta.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
@@ -65,7 +83,7 @@ public function render()
                 case DocumentProperties::PROPERTY_TYPE_INTEGER:
                 case DocumentProperties::PROPERTY_TYPE_FLOAT:
                     $objWriter->writeAttribute('meta:value-type', 'float');
-                    $objWriter->writeRaw($propertyValue);
+                    $objWriter->writeRaw((string) $propertyValue);
                     break;
                 case DocumentProperties::PROPERTY_TYPE_BOOLEAN:
                     $objWriter->writeAttribute('meta:value-type', 'boolean');
@@ -79,7 +97,7 @@ public function render()
                 case DocumentProperties::PROPERTY_TYPE_UNKNOWN:
                 default:
                     $objWriter->writeAttribute('meta:value-type', 'string');
-                    $objWriter->writeRaw($propertyValue);
+                    $objWriter->writeRaw((string) $propertyValue);
                     break;
             }
             $objWriter->endElement();
diff --git a/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php b/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
index 45330e38a..0265d47bf 100644
--- a/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
+++ b/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
diff --git a/src/PhpPresentation/Writer/ODPresentation/Mimetype.php b/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
index a6360a324..f364860be 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
diff --git a/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php b/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
index fa6078eda..4addc132a 100644
--- a/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
+++ b/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
@@ -163,8 +181,8 @@ protected function writeContentPart(Chart $chart): string
         $this->xmlContent->startElement('office:chart');
         // office:chart
         $this->xmlContent->startElement('chart:chart');
-        $this->xmlContent->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters($chart->getWidth()), 3) . 'cm');
-        $this->xmlContent->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters($chart->getHeight()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:width', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $chart->getWidth()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:height', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $chart->getHeight()), 3) . 'cm');
         $this->xmlContent->writeAttribute('xlink:href', '.');
         $this->xmlContent->writeAttribute('xlink:type', 'simple');
         $this->xmlContent->writeAttribute('chart:style-name', 'styleChart');
@@ -458,8 +476,8 @@ private function writeLegend(Chart $chart): void
                 break;
         }
         $this->xmlContent->writeAttribute('chart:legend-position', $position);
-        $this->xmlContent->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($chart->getLegend()->getOffsetX()), 3) . 'cm');
-        $this->xmlContent->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($chart->getLegend()->getOffsetY()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $chart->getLegend()->getOffsetX()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $chart->getLegend()->getOffsetY()), 3) . 'cm');
         $this->xmlContent->writeAttribute('style:legend-expansion', 'high');
         $this->xmlContent->writeAttribute('chart:style-name', 'styleLegend');
         // > chart:legend
@@ -913,8 +931,8 @@ private function writeTitle(Title $oTitle): void
         }
         // chart:title
         $this->xmlContent->startElement('chart:title');
-        $this->xmlContent->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters($oTitle->getOffsetX()), 3) . 'cm');
-        $this->xmlContent->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters($oTitle->getOffsetY()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:x', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $oTitle->getOffsetX()), 3) . 'cm');
+        $this->xmlContent->writeAttribute('svg:y', Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $oTitle->getOffsetY()), 3) . 'cm');
         $this->xmlContent->writeAttribute('chart:style-name', 'styleTitle');
         // > text:p
         $this->xmlContent->startElement('text:p');
diff --git a/src/PhpPresentation/Writer/ODPresentation/Pictures.php b/src/PhpPresentation/Writer/ODPresentation/Pictures.php
index 16af2c76c..405c6b184 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Pictures.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Pictures.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
diff --git a/src/PhpPresentation/Writer/ODPresentation/Styles.php b/src/PhpPresentation/Writer/ODPresentation/Styles.php
index 766cb094a..351e8a205 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Styles.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Styles.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
@@ -136,8 +154,8 @@ protected function writePart(): string
         $objWriter->writeAttribute('fo:margin-bottom', '0cm');
         $objWriter->writeAttribute('fo:margin-left', '0cm');
         $objWriter->writeAttribute('fo:margin-right', '0cm');
-        $objWriter->writeAttribute('fo:page-width', Text::numberFormat(CommonDrawing::pixelsToCentimeters(CommonDrawing::emuToPixels($this->getPresentation()->getLayout()->getCX())), 1) . 'cm');
-        $objWriter->writeAttribute('fo:page-height', Text::numberFormat(CommonDrawing::pixelsToCentimeters(CommonDrawing::emuToPixels($this->getPresentation()->getLayout()->getCY())), 1) . 'cm');
+        $objWriter->writeAttribute('fo:page-width', Text::numberFormat(CommonDrawing::pixelsToCentimeters(CommonDrawing::emuToPixels((int) $this->getPresentation()->getLayout()->getCX())), 1) . 'cm');
+        $objWriter->writeAttribute('fo:page-height', Text::numberFormat(CommonDrawing::pixelsToCentimeters(CommonDrawing::emuToPixels((int) $this->getPresentation()->getLayout()->getCY())), 1) . 'cm');
         $printOrientation = 'portrait';
         if ($this->getPresentation()->getLayout()->getCX() > $this->getPresentation()->getLayout()->getCY()) {
             $printOrientation = 'landscape';
diff --git a/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php b/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
index 087dd042d..7e9988983 100644
--- a/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
+++ b/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\ODPresentation;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007.php b/src/PhpPresentation/Writer/PowerPoint2007.php
index f3ff5f418..db43657ff 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer;
 
 use DirectoryIterator;
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
index 802098b7f..7e9eff342 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
@@ -217,7 +235,7 @@ protected function writeGradientFill(XMLWriter $objWriter, Fill $pFill): void
 
         // a:lin
         $objWriter->startElement('a:lin');
-        $objWriter->writeAttribute('ang', CommonDrawing::degreesToAngle($pFill->getRotation()));
+        $objWriter->writeAttribute('ang', CommonDrawing::degreesToAngle((int) $pFill->getRotation()));
         $objWriter->writeAttribute('scaled', '0');
         $objWriter->endElement();
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php b/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
index 4b3bea8a8..dbb7c53fd 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
 use ArrayObject;
@@ -206,7 +208,7 @@ protected function writeShapeText(XMLWriter $objWriter, RichText $shape, int $sh
         if (!$shape->isPlaceholder()) {
             // p:sp\p:spPr\a:xfrm
             $objWriter->startElement('a:xfrm');
-            $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle($shape->getRotation()));
+            $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle((int) $shape->getRotation()));
             // p:sp\p:spPr\a:xfrm\a:off
             $objWriter->startElement('a:off');
             $objWriter->writeAttribute('x', CommonDrawing::pixelsToEmu($shape->getOffsetX()));
@@ -763,7 +765,7 @@ protected function writeShadow(XMLWriter $objWriter, Shadow $oShadow): void
         $objWriter->startElement('a:outerShdw');
         $objWriter->writeAttribute('blurRad', CommonDrawing::pixelsToEmu($oShadow->getBlurRadius()));
         $objWriter->writeAttribute('dist', CommonDrawing::pixelsToEmu($oShadow->getDistance()));
-        $objWriter->writeAttribute('dir', CommonDrawing::degreesToAngle($oShadow->getDirection()));
+        $objWriter->writeAttribute('dir', CommonDrawing::degreesToAngle((int) $oShadow->getDirection()));
         $objWriter->writeAttribute('algn', $oShadow->getAlignment());
         $objWriter->writeAttribute('rotWithShape', '0');
 
@@ -1116,7 +1118,7 @@ protected function writeShapeAutoShape(XMLWriter $objWriter, AutoShape $shape, i
 
         // p:sp\p:spPr\a:xfrm
         $objWriter->startElement('a:xfrm');
-        $objWriter->writeAttributeIf($shape->getRotation() != 0, 'rot', CommonDrawing::degreesToAngle($shape->getRotation()));
+        $objWriter->writeAttributeIf($shape->getRotation() != 0, 'rot', CommonDrawing::degreesToAngle((int) $shape->getRotation()));
         // p:sp\p:spPr\a:xfrm\a:off
         $objWriter->startElement('a:off');
         $objWriter->writeAttribute('x', CommonDrawing::pixelsToEmu($shape->getOffsetX()));
@@ -1210,7 +1212,7 @@ protected function writeShapeChart(XMLWriter $objWriter, ShapeChart $shape, int
         $objWriter->endElement();
         // p:xfrm
         $objWriter->startElement('p:xfrm');
-        $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle($shape->getRotation()));
+        $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle((int) $shape->getRotation()));
         // a:off
         $objWriter->startElement('a:off');
         $objWriter->writeAttribute('x', CommonDrawing::pixelsToEmu($shape->getOffsetX()));
@@ -1377,7 +1379,7 @@ protected function writeShapePic(XMLWriter $objWriter, AbstractGraphic $shape, i
         $objWriter->startElement('p:spPr');
         // a:xfrm
         $objWriter->startElement('a:xfrm');
-        $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle($shape->getRotation()));
+        $objWriter->writeAttributeIf(0 != $shape->getRotation(), 'rot', CommonDrawing::degreesToAngle((int) $shape->getRotation()));
 
         // a:off
         $objWriter->startElement('a:off');
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php b/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
index 437feba36..4471b612f 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php b/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
index 2f4184e2f..e0293817e 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
 use PhpOffice\Common\XMLWriter;
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
index e6fa24cbe..4df4d6a55 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
index f0d55269c..9aef8a6c7 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
index 47f0651bb..e80b8fd0e 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
@@ -53,13 +71,13 @@ public function render()
             $objWriter->writeAttribute('name', $customProperty);
             switch ($propertyType) {
                 case DocumentProperties::PROPERTY_TYPE_INTEGER:
-                    $objWriter->writeElement('vt:i4', $propertyValue);
+                    $objWriter->writeElement('vt:i4', (string) $propertyValue);
                     break;
                 case DocumentProperties::PROPERTY_TYPE_FLOAT:
-                    $objWriter->writeElement('vt:r8', $propertyValue);
+                    $objWriter->writeElement('vt:r8', (string) $propertyValue);
                     break;
                 case DocumentProperties::PROPERTY_TYPE_BOOLEAN:
-                    $objWriter->writeElement('vt:bool', ($propertyValue) ? 'true' : 'false');
+                    $objWriter->writeElement('vt:bool', $propertyValue ? 'true' : 'false');
                     break;
                 case DocumentProperties::PROPERTY_TYPE_DATE:
                     $objWriter->startElement('vt:filetime');
@@ -67,7 +85,7 @@ public function render()
                     $objWriter->endElement();
                     break;
                 default:
-                    $objWriter->writeElement('vt:lpwstr', $propertyValue);
+                    $objWriter->writeElement('vt:lpwstr', (string) $propertyValue);
                     break;
             }
             $objWriter->endElement();
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
index f6dde3826..b9ec15199 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php b/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
index a5837fdc6..125bf1342 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
@@ -174,7 +192,7 @@ public function writeChart(Chart $chart): string
             $objWriter->startElement('a:outerShdw');
             $objWriter->writeAttribute('blurRad', CommonDrawing::pixelsToEmu($chart->getShadow()->getBlurRadius()));
             $objWriter->writeAttribute('dist', CommonDrawing::pixelsToEmu($chart->getShadow()->getDistance()));
-            $objWriter->writeAttribute('dir', CommonDrawing::degreesToAngle($chart->getShadow()->getDirection()));
+            $objWriter->writeAttribute('dir', CommonDrawing::degreesToAngle((int) $chart->getShadow()->getDirection()));
             $objWriter->writeAttribute('algn', $chart->getShadow()->getAlignment());
             $objWriter->writeAttribute('rotWithShape', '0');
 
@@ -845,7 +863,7 @@ protected function writeTypeBar(XMLWriter $objWriter, Bar $subject, bool $includ
                 $objWriter->startElement('c:dPt');
 
                 // c:idx
-                $this->writeElementWithValAttribute($objWriter, 'c:idx', $key);
+                $this->writeElementWithValAttribute($objWriter, 'c:idx', (string) $key);
 
                 if (Fill::FILL_NONE != $value->getFillType()) {
                     // c:spPr
@@ -1058,7 +1076,7 @@ protected function writeTypeBar3D(XMLWriter $objWriter, Bar3D $subject, bool $in
                 $objWriter->startElement('c:dPt');
 
                 // c:idx
-                $this->writeElementWithValAttribute($objWriter, 'c:idx', $key);
+                $this->writeElementWithValAttribute($objWriter, 'c:idx', (string) $key);
 
                 if (Fill::FILL_NONE != $value->getFillType()) {
                     // c:spPr
@@ -1244,7 +1262,7 @@ protected function writeTypeDoughnut(XMLWriter $objWriter, Doughnut $subject, bo
             foreach ($dataPointFills as $key => $value) {
                 // c:dPt
                 $objWriter->startElement('c:dPt');
-                $this->writeElementWithValAttribute($objWriter, 'c:idx', $key);
+                $this->writeElementWithValAttribute($objWriter, 'c:idx', (string) $key);
                 // c:dPt/c:spPr
                 $objWriter->startElement('c:spPr');
                 $this->writeFill($objWriter, $value);
@@ -1403,7 +1421,7 @@ protected function writeTypePie(XMLWriter $objWriter, Pie $subject, bool $includ
             foreach ($dataPointFills as $key => $value) {
                 // c:dPt
                 $objWriter->startElement('c:dPt');
-                $this->writeElementWithValAttribute($objWriter, 'c:idx', $key);
+                $this->writeElementWithValAttribute($objWriter, 'c:idx', (string) $key);
                 // c:dPt/c:spPr
                 $objWriter->startElement('c:spPr');
                 $this->writeFill($objWriter, $value);
@@ -1573,7 +1591,7 @@ protected function writeTypePie3D(XMLWriter $objWriter, Pie3D $subject, bool $in
             foreach ($dataPointFills as $key => $value) {
                 // c:dPt
                 $objWriter->startElement('c:dPt');
-                $this->writeElementWithValAttribute($objWriter, 'c:idx', $key);
+                $this->writeElementWithValAttribute($objWriter, 'c:idx', (string) $key);
                 // c:dPt/c:spPr
                 $objWriter->startElement('c:spPr');
                 $this->writeFill($objWriter, $value);
@@ -2362,7 +2380,7 @@ protected function writeAxis(XMLWriter $objWriter, Chart\Axis $oAxis, string $ty
 
             // a:bodyPr
             $objWriter->startElement('a:bodyPr');
-            $objWriter->writeAttributeIf($oAxis->getTitleRotation() != 0, 'rot', CommonDrawing::degreesToAngle($oAxis->getTitleRotation()));
+            $objWriter->writeAttributeIf($oAxis->getTitleRotation() != 0, 'rot', CommonDrawing::degreesToAngle((int) $oAxis->getTitleRotation()));
             $objWriter->endElement();
 
             // a:lstStyle
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php b/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
index 0bae8b149..060fec0bf 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php b/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
index 8c8286e2f..bbbe22f9f 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
index d2a8674c0..10585295b 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php b/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
index 2250866b9..63c138c2e 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
index 51d0aae7f..b9730e3aa 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
index 9a7f99dbb..5db12b952 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
index 2d7773c82..7ef785e34 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
index 6467c5b72..c567721ef 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php b/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
index 7b261417a..efc07a618 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
index 69aa13015..1871fb31b 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php b/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
index 64ca70067..34f70a978 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Writer\PowerPoint2007;
 
diff --git a/src/PhpPresentation/Writer/Serialized.php b/src/PhpPresentation/Writer/Serialized.php
index 894f4cbff..8d04d9423 100644
--- a/src/PhpPresentation/Writer/Serialized.php
+++ b/src/PhpPresentation/Writer/Serialized.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer;
 
 use PhpOffice\Common\Adapter\Zip\ZipArchiveAdapter;
diff --git a/src/PhpPresentation/Writer/WriterInterface.php b/src/PhpPresentation/Writer/WriterInterface.php
index abc6b53b2..55112facb 100644
--- a/src/PhpPresentation/Writer/WriterInterface.php
+++ b/src/PhpPresentation/Writer/WriterInterface.php
@@ -16,6 +16,8 @@
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Writer;
 
 /**
diff --git a/tests/PhpPresentation/Tests/AbstractShapeTest.php b/tests/PhpPresentation/Tests/AbstractShapeTest.php
index c003b293e..3b0c0eb23 100644
--- a/tests/PhpPresentation/Tests/AbstractShapeTest.php
+++ b/tests/PhpPresentation/Tests/AbstractShapeTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
- * @copyright   2010-2014 PhpPresentation contributors
- * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
  * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/tests/PhpPresentation/Tests/AutoloaderTest.php b/tests/PhpPresentation/Tests/AutoloaderTest.php
index 8da3f8769..c1b32c0c4 100644
--- a/tests/PhpPresentation/Tests/AutoloaderTest.php
+++ b/tests/PhpPresentation/Tests/AutoloaderTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
- * @copyright   2010-2014 PhpPresentation contributors
- * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
  * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\Autoloader;
diff --git a/tests/PhpPresentation/Tests/DocumentLayoutTest.php b/tests/PhpPresentation/Tests/DocumentLayoutTest.php
index 53c1e1a73..1d1c1c488 100644
--- a/tests/PhpPresentation/Tests/DocumentLayoutTest.php
+++ b/tests/PhpPresentation/Tests/DocumentLayoutTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\DocumentLayout;
diff --git a/tests/PhpPresentation/Tests/DocumentPropertiesTest.php b/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
index 273428fa1..3e520d045 100644
--- a/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
+++ b/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\DocumentProperties;
diff --git a/tests/PhpPresentation/Tests/HashTableTest.php b/tests/PhpPresentation/Tests/HashTableTest.php
index d68027229..18c3a149a 100644
--- a/tests/PhpPresentation/Tests/HashTableTest.php
+++ b/tests/PhpPresentation/Tests/HashTableTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\HashTable;
diff --git a/tests/PhpPresentation/Tests/IOFactoryTest.php b/tests/PhpPresentation/Tests/IOFactoryTest.php
index 0f988eb9c..223fc5532 100644
--- a/tests/PhpPresentation/Tests/IOFactoryTest.php
+++ b/tests/PhpPresentation/Tests/IOFactoryTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\IOFactory;
@@ -56,7 +58,7 @@ public function testLoadClassException(): void
     {
         $this->expectException(\Exception::class);
         $this->expectExceptionMessage('"" is not a valid reader');
-        IOFactory::createReader();
+        IOFactory::createReader('');
     }
 
     public function testLoad(): void
diff --git a/tests/PhpPresentation/Tests/PhpPresentationTest.php b/tests/PhpPresentation/Tests/PhpPresentationTest.php
index 83232f0f8..8d5acc2a0 100644
--- a/tests/PhpPresentation/Tests/PhpPresentationTest.php
+++ b/tests/PhpPresentation/Tests/PhpPresentationTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\DocumentLayout;
diff --git a/tests/PhpPresentation/Tests/PresentationPropertiesTest.php b/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
index 8a076b7f1..56d88f5d4 100644
--- a/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
+++ b/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\PresentationProperties;
diff --git a/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php b/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
index 235cdc9b9..ddbfdf03f 100644
--- a/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Reader;
 
 use PhpOffice\PhpPresentation\PresentationProperties;
diff --git a/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php b/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
index 45eb67bd4..57c5133ec 100644
--- a/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
+++ b/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Reader;
 
 use PhpOffice\PhpPresentation\DocumentLayout;
diff --git a/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php b/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
index 86bb14280..87c9c403c 100644
--- a/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
+++ b/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Reader;
 
 use PhpOffice\PhpPresentation\Reader\PowerPoint97;
diff --git a/tests/PhpPresentation/Tests/Reader/SerializedTest.php b/tests/PhpPresentation/Tests/Reader/SerializedTest.php
index 164b5debf..f1d057cd0 100644
--- a/tests/PhpPresentation/Tests/Reader/SerializedTest.php
+++ b/tests/PhpPresentation/Tests/Reader/SerializedTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Reader;
 
 use PhpOffice\PhpPresentation\Reader\Serialized;
diff --git a/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php b/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
index 2428f8c79..54d6cf41e 100644
--- a/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
+++ b/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\AbstractGraphic;
diff --git a/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php b/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
index dbeea6713..9e235e2df 100644
--- a/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
+++ b/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\AutoShape;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php b/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
index 7ae33da24..8696d3874 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Axis;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php b/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
index d7e725cfb..fe0e96451 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php b/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
index d4c62f51c..3b57adbb2 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Legend;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php b/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
index 8e2d6bf26..9904ea660 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Marker;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php b/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
index 12c5420f5..5c2fdc898 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\PlotArea;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php b/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
index 6da4ae0ab..f3cc6b7b1 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Marker;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php b/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
index 2837d05ff..a2e076451 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Title;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
index 7cb5e0e49..d19327eba 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
index 435aed9d0..e1eba28f6 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
index 20beea5a6..68df16e1f 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
index a6c68a7f8..8b7dbd7dc 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
index 62d3f092b..a6c8a2204 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
index 043b5d79c..05b6cb6f3 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
index 6cb06b6e1..33f825c17 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
index 8ec172033..42f5b5d6a 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
index 3957c2fb5..07a3cb2f9 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
index bb430770c..ca8134be7 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart\Type;
 
 use PhpOffice\PhpPresentation\Shape\Chart\Series;
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
index 0b520a21a..f86d39fb1 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Chart;
 
 use PhpOffice\PhpPresentation\Shape\Chart\View3D;
diff --git a/tests/PhpPresentation/Tests/Shape/ChartTest.php b/tests/PhpPresentation/Tests/Shape/ChartTest.php
index a042fa8df..b51d85775 100644
--- a/tests/PhpPresentation/Tests/Shape/ChartTest.php
+++ b/tests/PhpPresentation/Tests/Shape/ChartTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Chart;
diff --git a/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php b/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
index f04e3cae8..e70554246 100644
--- a/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Comment;
 
 use PhpOffice\PhpPresentation\Shape\Comment\Author;
diff --git a/tests/PhpPresentation/Tests/Shape/CommentTest.php b/tests/PhpPresentation/Tests/Shape/CommentTest.php
index e71ba9dd3..b1c3490e7 100644
--- a/tests/PhpPresentation/Tests/Shape/CommentTest.php
+++ b/tests/PhpPresentation/Tests/Shape/CommentTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Comment;
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php b/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
index b85f35b1c..916a1b452 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Drawing;
 
 use PhpOffice\PhpPresentation\Shape\Drawing\Base64;
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php b/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
index 7e9f5c258..81744cb21 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Drawing;
 
 use PhpOffice\PhpPresentation\Shape\Drawing\File;
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php b/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
index 92ab8ac91..5bc76abb3 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Drawing;
 
 use PhpOffice\PhpPresentation\Shape\Drawing\ZipFile;
diff --git a/tests/PhpPresentation/Tests/Shape/GroupTest.php b/tests/PhpPresentation/Tests/Shape/GroupTest.php
index a71bc8bb7..85cb4cd60 100644
--- a/tests/PhpPresentation/Tests/Shape/GroupTest.php
+++ b/tests/PhpPresentation/Tests/Shape/GroupTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Group;
diff --git a/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php b/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
index 9b95d326d..991f72852 100644
--- a/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
+++ b/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Hyperlink;
diff --git a/tests/PhpPresentation/Tests/Shape/LineTest.php b/tests/PhpPresentation/Tests/Shape/LineTest.php
index 8427936c2..12ada1531 100644
--- a/tests/PhpPresentation/Tests/Shape/LineTest.php
+++ b/tests/PhpPresentation/Tests/Shape/LineTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Line;
diff --git a/tests/PhpPresentation/Tests/Shape/MediaTest.php b/tests/PhpPresentation/Tests/Shape/MediaTest.php
index f2c9ec380..14508464c 100644
--- a/tests/PhpPresentation/Tests/Shape/MediaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/MediaTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Shape;
 
diff --git a/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php b/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
index f89e4dca0..eb741d24f 100644
--- a/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
+++ b/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Placeholder;
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php b/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
index cec5d856c..512af22a9 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Shape\RichText\BreakElement;
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php b/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
index 292cf2a95..be34b6f1c 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Shape\RichText\Paragraph;
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php b/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
index 4227820b4..0deb0b333 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Shape\RichText\Run;
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php b/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
index 4931a17e8..f63de69d4 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\RichText;
 
 use PhpOffice\PhpPresentation\Shape\Hyperlink;
diff --git a/tests/PhpPresentation/Tests/Shape/RichTextTest.php b/tests/PhpPresentation/Tests/Shape/RichTextTest.php
index 88936c78c..c1b78f905 100644
--- a/tests/PhpPresentation/Tests/Shape/RichTextTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichTextTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\RichText;
diff --git a/tests/PhpPresentation/Tests/Shape/Table/CellTest.php b/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
index aeefaab1a..017fb61b6 100644
--- a/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Table;
 
 use PhpOffice\PhpPresentation\Shape\RichText\Paragraph;
diff --git a/tests/PhpPresentation/Tests/Shape/Table/RowTest.php b/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
index 0a5627fa1..2dce4c8d1 100644
--- a/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape\Table;
 
 use PhpOffice\PhpPresentation\Shape\Table\Row;
diff --git a/tests/PhpPresentation/Tests/Shape/TableTest.php b/tests/PhpPresentation/Tests/Shape/TableTest.php
index 0d790effa..91e803c01 100644
--- a/tests/PhpPresentation/Tests/Shape/TableTest.php
+++ b/tests/PhpPresentation/Tests/Shape/TableTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Shape;
 
 use PhpOffice\PhpPresentation\Shape\Table;
diff --git a/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php b/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
index 1ae46c3b9..16fd59778 100644
--- a/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
+++ b/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Slide;
 
 use PhpOffice\PhpPresentation\Shape\RichText;
diff --git a/tests/PhpPresentation/Tests/Slide/AnimationTest.php b/tests/PhpPresentation/Tests/Slide/AnimationTest.php
index 686d15953..84d48cee0 100644
--- a/tests/PhpPresentation/Tests/Slide/AnimationTest.php
+++ b/tests/PhpPresentation/Tests/Slide/AnimationTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php b/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
index 9f64af2da..02946f7a8 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Slide\Background;
 
diff --git a/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php b/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
index 286f02b61..edeeae37c 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Slide\Background;
 
diff --git a/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php b/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
index 7da7cda09..cdf5142ff 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Slide\Background;
 
diff --git a/tests/PhpPresentation/Tests/Slide/IteratorTest.php b/tests/PhpPresentation/Tests/Slide/IteratorTest.php
index 4e0509e21..480e874d4 100644
--- a/tests/PhpPresentation/Tests/Slide/IteratorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/IteratorTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Slide;
 
 use PhpOffice\PhpPresentation\PhpPresentation;
diff --git a/tests/PhpPresentation/Tests/Slide/NoteTest.php b/tests/PhpPresentation/Tests/Slide/NoteTest.php
index c94faa9e0..7b40555fb 100644
--- a/tests/PhpPresentation/Tests/Slide/NoteTest.php
+++ b/tests/PhpPresentation/Tests/Slide/NoteTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\PhpPresentation;
diff --git a/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php b/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
index c72fc6886..2fc7f7df0 100644
--- a/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
+++ b/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\Slide\SlideLayout;
diff --git a/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php b/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
index 91d247061..4bda4aa51 100644
--- a/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
+++ b/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\Slide\Background\Color;
diff --git a/tests/PhpPresentation/Tests/Slide/TransitionTest.php b/tests/PhpPresentation/Tests/Slide/TransitionTest.php
index 60967e451..5afda6050 100644
--- a/tests/PhpPresentation/Tests/Slide/TransitionTest.php
+++ b/tests/PhpPresentation/Tests/Slide/TransitionTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\Slide\Transition;
diff --git a/tests/PhpPresentation/Tests/SlideTest.php b/tests/PhpPresentation/Tests/SlideTest.php
index 9da5cd930..eea3f731d 100644
--- a/tests/PhpPresentation/Tests/SlideTest.php
+++ b/tests/PhpPresentation/Tests/SlideTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests;
 
 use PhpOffice\PhpPresentation\PhpPresentation;
diff --git a/tests/PhpPresentation/Tests/Style/AlignmentTest.php b/tests/PhpPresentation/Tests/Style/AlignmentTest.php
index e10d550da..2a1a16a90 100644
--- a/tests/PhpPresentation/Tests/Style/AlignmentTest.php
+++ b/tests/PhpPresentation/Tests/Style/AlignmentTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Alignment;
diff --git a/tests/PhpPresentation/Tests/Style/BorderTest.php b/tests/PhpPresentation/Tests/Style/BorderTest.php
index 98f8574e5..6084fa10c 100644
--- a/tests/PhpPresentation/Tests/Style/BorderTest.php
+++ b/tests/PhpPresentation/Tests/Style/BorderTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Border;
diff --git a/tests/PhpPresentation/Tests/Style/BordersTest.php b/tests/PhpPresentation/Tests/Style/BordersTest.php
index dd8657a03..72e9ce8bf 100644
--- a/tests/PhpPresentation/Tests/Style/BordersTest.php
+++ b/tests/PhpPresentation/Tests/Style/BordersTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Border;
diff --git a/tests/PhpPresentation/Tests/Style/BulletTest.php b/tests/PhpPresentation/Tests/Style/BulletTest.php
index febddf719..8d8b96563 100644
--- a/tests/PhpPresentation/Tests/Style/BulletTest.php
+++ b/tests/PhpPresentation/Tests/Style/BulletTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Bullet;
diff --git a/tests/PhpPresentation/Tests/Style/ColorMapTest.php b/tests/PhpPresentation/Tests/Style/ColorMapTest.php
index 6aeb5f3ce..126c80ac1 100644
--- a/tests/PhpPresentation/Tests/Style/ColorMapTest.php
+++ b/tests/PhpPresentation/Tests/Style/ColorMapTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\ColorMap;
diff --git a/tests/PhpPresentation/Tests/Style/ColorTest.php b/tests/PhpPresentation/Tests/Style/ColorTest.php
index 51864fff7..afdfcd26a 100644
--- a/tests/PhpPresentation/Tests/Style/ColorTest.php
+++ b/tests/PhpPresentation/Tests/Style/ColorTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Color;
@@ -49,7 +51,7 @@ public function testAlpha(): void
         $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB());
         $this->assertEquals(100, $object->getAlpha());
         $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB('AA0000FF'));
-        $this->assertEquals(66.67, $object->getAlpha());
+        $this->assertEquals(67, $object->getAlpha());
         $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(Color::COLOR_BLUE));
         $this->assertEquals(100, $object->getAlpha());
         $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setAlpha($randAlpha));
diff --git a/tests/PhpPresentation/Tests/Style/FillTest.php b/tests/PhpPresentation/Tests/Style/FillTest.php
index 8e9e88571..2ac5eb183 100644
--- a/tests/PhpPresentation/Tests/Style/FillTest.php
+++ b/tests/PhpPresentation/Tests/Style/FillTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Color;
diff --git a/tests/PhpPresentation/Tests/Style/FontTest.php b/tests/PhpPresentation/Tests/Style/FontTest.php
index 0952f5459..47deb3f0b 100644
--- a/tests/PhpPresentation/Tests/Style/FontTest.php
+++ b/tests/PhpPresentation/Tests/Style/FontTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Color;
diff --git a/tests/PhpPresentation/Tests/Style/OutlineTest.php b/tests/PhpPresentation/Tests/Style/OutlineTest.php
index 48632922d..30411f12b 100644
--- a/tests/PhpPresentation/Tests/Style/OutlineTest.php
+++ b/tests/PhpPresentation/Tests/Style/OutlineTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Fill;
diff --git a/tests/PhpPresentation/Tests/Style/ShadowTest.php b/tests/PhpPresentation/Tests/Style/ShadowTest.php
index 2336bb70e..ec2286982 100644
--- a/tests/PhpPresentation/Tests/Style/ShadowTest.php
+++ b/tests/PhpPresentation/Tests/Style/ShadowTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Style\Color;
diff --git a/tests/PhpPresentation/Tests/Style/TextStyleTest.php b/tests/PhpPresentation/Tests/Style/TextStyleTest.php
index d84f7d771..b85da8f1f 100644
--- a/tests/PhpPresentation/Tests/Style/TextStyleTest.php
+++ b/tests/PhpPresentation/Tests/Style/TextStyleTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Style;
 
 use PhpOffice\PhpPresentation\Shape\RichText\Paragraph;
diff --git a/tests/PhpPresentation/Tests/Writer/AbstractWriter.php b/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
index b0f348eab..7da382b97 100644
--- a/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
+++ b/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
- * @copyright   2009-2017 PHPPresentation contributors
- * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
  * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Writer;
 
 use PhpOffice\PhpPresentation\AbstractShape;
diff --git a/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php b/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
index 5b2fda6f4..101ed117c 100644
--- a/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
+++ b/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Writer;
 
 use PhpOffice\Common\Adapter\Zip\ZipInterface;
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
index 1b8e093dd..c67a78bc9 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\ODPresentation;
 
@@ -268,10 +286,10 @@ public function testMedia(): void
             ->setOffsetY($expectedY);
         $this->oPresentation->getActiveSlide()->addShape($oMedia);
 
-        $expectedWidth = Text::numberFormat(CommonDrawing::pixelsToCentimeters($expectedWidth), 3) . 'cm';
-        $expectedHeight = Text::numberFormat(CommonDrawing::pixelsToCentimeters($expectedHeight), 3) . 'cm';
-        $expectedX = Text::numberFormat(CommonDrawing::pixelsToCentimeters($expectedX), 3) . 'cm';
-        $expectedY = Text::numberFormat(CommonDrawing::pixelsToCentimeters($expectedY), 3) . 'cm';
+        $expectedWidth = Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $expectedWidth), 3) . 'cm';
+        $expectedHeight = Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $expectedHeight), 3) . 'cm';
+        $expectedX = Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $expectedX), 3) . 'cm';
+        $expectedY = Text::numberFormat(CommonDrawing::pixelsToCentimeters((int) $expectedY), 3) . 'cm';
 
         $element = '/office:document-content/office:body/office:presentation/draw:page/draw:frame';
         $this->assertZipXmlElementExists('content.xml', $element);
@@ -512,9 +530,9 @@ public function testRichTextShadow(): void
                 $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-x', '0cm');
             } else {
                 if ($inc > 90 && $inc < 270) {
-                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-x', '-' . Drawing::pixelsToCentimeters($randDistance) . 'cm');
+                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-x', '-' . Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
                 } else {
-                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-x', Drawing::pixelsToCentimeters($randDistance) . 'cm');
+                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-x', Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
                 }
             }
             // Y
@@ -522,9 +540,9 @@ public function testRichTextShadow(): void
                 $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', '0cm');
             } else {
                 if (($inc > 0 && $inc < 180) || 360 == $inc) {
-                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', Drawing::pixelsToCentimeters($randDistance) . 'cm');
+                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
                 } else {
-                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', '-' . Drawing::pixelsToCentimeters($randDistance) . 'cm');
+                    $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', '-' . Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
                 }
             }
             $this->assertIsSchemaOpenDocumentValid('1.2');
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
index 88a5326c1..be0019b23 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\ODPresentation;
 
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
index 9b30a7df0..a6a142e69 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\ODPresentation;
 
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
index 2a27f32bd..59e668c8a 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\ODPresentation;
 
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
index 25ddd07d4..523087adf 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\ODPresentation;
 
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
index cd0cf0a84..cbcc67dc4 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
index d06f8782f..18552dbbc 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
index 298f1e728..fc9ba5aef 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
@@ -1,11 +1,23 @@
 <?php
 /**
- * Created by PhpStorm.
- * User: lefevre_f
- * Date: 01/03/2016
- * Time: 12:35.
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
+declare(strict_types=1);
+
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
 use PhpOffice\PhpPresentation\Tests\PhpPresentationTestCase;
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
index 01fb7284a..2f7f87732 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
index 3c28e1303..057b2b839 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
index b563266a3..c65bba64e 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
index a01993079..01bb66e3f 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
@@ -448,7 +466,7 @@ public function testAxisTitleRotation(): void
         $element = '/c:chartSpace/c:chart/c:plotArea/c:catAx/c:title/c:tx/c:rich/a:bodyPr';
         $this->assertZipXmlElementExists($pathShape, $element);
         $this->assertZipXmlAttributeExists($pathShape, $element, 'rot');
-        $this->assertZipXmlAttributeEquals($pathShape, $element, 'rot', Drawing::degreesToAngle($value));
+        $this->assertZipXmlAttributeEquals($pathShape, $element, 'rot', Drawing::degreesToAngle((int) $value));
     }
 
     public function testAxisVisibility(): void
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
index 3e202c61d..8c67c8ac7 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
index 3d428d6d9..4029b36b6 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
index b6fdd2978..6acf0e83b 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
index 17bfe64ac..b3b02454a 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
index cc974192e..bc99f27c7 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
index 7592bd42f..0d0f60681 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
index 3e2a782a0..dd4957b0d 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
index 6a9c6780f..a2bed9edf 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
index 27f9eaeca..015e5464c 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer\PowerPoint2007;
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
index 9ce81f02e..bb13cfdcf 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests\Writer;
 
diff --git a/tests/PhpPresentation/Tests/Writer/SerializedTest.php b/tests/PhpPresentation/Tests/Writer/SerializedTest.php
index 3f51acba6..b0274e6b6 100644
--- a/tests/PhpPresentation/Tests/Writer/SerializedTest.php
+++ b/tests/PhpPresentation/Tests/Writer/SerializedTest.php
@@ -10,12 +10,14 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
  * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
- * @see        https://github.com/PHPOffice/PHPPresentation
  */
 
+declare(strict_types=1);
+
 namespace PhpOffice\PhpPresentation\Tests\Writer;
 
 use PhpOffice\PhpPresentation\PhpPresentation;
diff --git a/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php b/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
index 95d2d9968..77cba12ca 100644
--- a/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
+++ b/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
@@ -1,4 +1,22 @@
 <?php
+/**
+ * This file is part of PHPPresentation - A pure PHP library for reading and writing
+ * presentations documents.
+ *
+ * PHPPresentation is free software distributed under the terms of the GNU Lesser
+ * General Public License version 3 as published by the Free Software Foundation.
+ *
+ * For the full copyright and license information, please read the LICENSE
+ * file that was distributed with this source code. For the full list of
+ * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
+ *
+ * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
+ */
+
+declare(strict_types=1);
 
 namespace PhpOffice\PhpPresentation\Tests;
 
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index c7c677661..88d30d03c 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -10,11 +10,13 @@
  * file that was distributed with this source code. For the full list of
  * contributors, visit https://github.com/PHPOffice/PHPPresentation/contributors.
  *
- * @copyright   2010-2014 PhpPresentation contributors
- * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
- *
  * @see        https://github.com/PHPOffice/PHPPresentation
+ *
+ * @copyright   2009-2015 PHPPresentation contributors
+ * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
+
+declare(strict_types=1);
 date_default_timezone_set('UTC');
 
 // defining base dir for tests