Stutter and lag when playing multiple samples repeatedly

[trackme518]

When using SoundFile class and triggering samples repeatedly it will start to stutter eventually. This is not happening in another audio library - Beads. Also reported here: https://discourse.processing.org/t/sound-library-bugs-lagging-noise-choppy/4718 Example code below:

import processing.sound.*;

int timer;
SoundFile[] file = new SoundFile[5];

void setup() {
  size(640, 480);
  background(0);
  for (int i=0; i<file.length; i++) {
    file[i] = new SoundFile(this, "http://soundbible.com/grab.php?id=1705&type=wav" );
  }
  timer = millis();

  frameRate(30);
}


int numplays = 0;

void draw() {
  //around 800-1100 plays it will start to stutter
  if (numplays<1000) {
    if (millis() > timer + 20 ) {
      int i = (int)random(0, file.length);
      file[i].play();
      numplays++;
      println(numplays);
      timer = millis();
    }
  }
}

[kevinstadler]

Thanks for reporting! Presumably this is an issue with how extra JSyn data players are allocated ad hoc when a sound file that is already playing is cued to start another playback... This will require a bit of debugging around here to figure out whether the issue is with the JSyn engine being overloaded, or if it's a general garbage collection issue (in which case this TODO finally needs implementing...):

processing-sound/src/processing/sound/AudioSample.java

Lines 305 to 320 in d508007

	// helper function: when called on a soundfile already running, the original
	// library triggered a second (concurrent) playback. with JSyn, every data
	// reader can only do one playback at a time, so if the present player
	// is busy we need to create a new one with the exact same settings and
	// trigger it instead (see JSyn's VoiceAllocator class)
	protected AudioSample getUnusedPlayer() {
	// TODO could implement a more intelligent player allocation pool method here to
	// limit the total number of playback voices
	if (this.isPlaying()) {
	// use private constructor which copies the sample as well as all playback
	// settings over
	return new AudioSample(this);
	} else {
	return this;
	}
	}

[trackme518]

Hi,
is it maybe possible to get number of used audio players at given time? So at least I could monitor it and restrict the max number....

[kevinstadler]

I had another look and it might not be just about the number of active audio players, but an issue of previously used but now inactive players staying connected to the synthesis engine forever. Could you do me a favour and try out the following test build and let me know if it improves the situation for you? sound.zip Just extract it into your Processing's libraries/ folder, replacing the sound directory that is already there.

I tried to test it with the sketch you posted above but I'm finding it difficult to hear past the clipping that's happening with too many simultaneous players, you probably have a better idea of what it should sound like...

(note that audiosample.loop() is probably not working in this build, all one-shot methods like .play(), .jump() etc should work as expected though)

[trackme518]

Hi, I just tested the provided lib build, and the behavior seems unchanged. Once the number of repeatedly played sounds exceeds the threshold, it will start to stutter even after the playback has finished.