Add methods for suppressing all Sound library info/warning messages to Sound() class

[besketh]

I was trying to read the amplitude of a .wav file at a given sample, n, so I used the
processing.sound.AudioSample#read(n)
function which gave me what I wanted, so I was happy, but then I noticed that the terminal was completely swamped with messages about how this was a stereo wave file and it was only giving the amplitude for the left channel. Messages which were completely inconsequential for me as I didn't care which channel the amplitude came from. This was annoying because I was monitoring certain params with the terminal output and it was impossible to find the figures amongst the spam. I thought it was using some kind of logging system which I could turn off but I looked into the source code and found that it was just using System.out.println(). I read into this more and realised that this is not good coding practice.

The example I gave is actually common throughout the codebase and many of the System.out.println() usages link back to this method:

processing.core.PApplet#println(java.lang.String)

I suggest that we use a more sophisticated logging package in place of this method to avoid the problems like the one I described

[kevinstadler]

Good call, looking back at that method in particular it's strange that I put a warning message instead of simply providing better documentation of what the method actually does. I'll remove that particular warning message (and add a separate read method where the channel number can be specified) to the next version. Thanks for reporting!

As for the occasional logging of other errors/warnings to the Processing console, those only occur when a sketch performs malformed/redundant operations on Sound objects, so they are really there to flag up potential coding problems to beginner users instead of them just sitting there wondering why no sound comes out. There's actually only one place where System.out.println() is called and that is the library's central Engine.printMessage() method which all those messages are funneled through. I'll add a library config option for suppressing all messages (and optionally also warnings) at runtime!

[besketh]

Thanks for the quick reply, and explanation :) your proposed improvements seem like a good resolution.

[kevinstadler]

No more warning redtext in the console with v2.3.1, which should become available from the Contribution Manager in the next couple of days (or for manual installation right now, from https://github.com/processing/processing-sound/releases/tag/v2.3.1).

@besketh just to clarify the behaviour of the read(int) method you've been using (which was actually incorrectly described by the warning message as well as documentation): say you have a 1 second stereo sample at a framerate of 44100, then sample.frames() will return 44100, but read(int) will actually access all 88200 data point of the stereo sample, in interleaved order:

• sample.read(0) returns the left channel sample at the first frame
• sample.read(1) returns the right channel sample at the first frame
• sample.read(44100) returns the left channel sample half a second into the file
• sample.read(88199) is the right channel sample at the very last frame

The release also contains a new example sketch which demonstrates the difference between read(index) and the newly added read(index, channel) method, in case you do want easy access to frames from both channels: https://github.com/processing/processing-sound/blob/8bc3339fd2a43431b22e82c4b38fa164bf57e3e0/examples/Soundfile/StereoSample/StereoSample.pde

Thanks again for reporting!

[besketh]

Nicely done! Cheers :)

[trackme518]

Hi, I still have these warning when setting the amplitude to 0 with version 2.4.0 - but this is intentional as I need to dynamically change volumes and at times assign 0 to certain channels.

In Engine.java line 606:

	// static helper methods that do stuff like checking argument values or 
	// printing library messages

	protected static boolean checkAmp(float amp) {
		if (amp < -1 || amp > 1) {
			Engine.printError("amplitude has to be in [-1,1]");
			return false;
		} else if (amp == 0.0) {
			Engine.printWarning("an amplitude of 0 means this sound is not audible now");
		}
		return true;
	}

What is the method to supress warnings?