Detect when the Shader is done mixing the audio - actionscript-3

Question

so this the code with it i am able to mix several tracks
with a Shader done in pixel bender.
the problem here i don't know when the mixing is finish or all the sound reache their end
to be able to save the bytearray into a file any Event or something like that
help plz ?
package
{
import flash.display.*;
import flash.media.*;
import flash.events.*;
import flash.net.*;
import flash.utils.*;
import fl.controls.Slider;
import org.bytearray.micrecorder.encoder.WaveEncoder;
[SWF(width='500', height='380', frameRate='24')]
public class AudioMixer extends Sprite{
[Embed(source = "sound2.mp3")] private var Track1:Class;
[Embed(source = "sound1.mp3")] private var Track2:Class;
[Embed(source = "mix.pbj",mimeType = "application/octet-stream")]
private var EmbedShader:Class;
private var shader:Shader = new Shader(new EmbedShader());
private var sound:Vector.<Sound> = new Vector.<Sound>();
private var bytes:Vector.<ByteArray> = new Vector.<ByteArray>();
private var sliders:Vector.<Slider> = new Vector.<Slider>();
private var graph:Vector.<Shape> = new Vector.<Shape>();
private var recBA:ByteArray = new ByteArray();
private var BUFFER_SIZE:int = 0x800;
public var playback:Sound = new Sound();
public var container:Sprite = new Sprite();
public var isEvent:Boolean = false;
public function AudioMixer():void{
container.y = stage.stageHeight * .5;
addChild(container);
sound.push(new Track1(), new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2(),new Track2());
for(var i:int = 0; i < sound.length; i++){
var slider:Slider = new Slider();
slider.maximum = 1;
slider.minimum = 0;
slider.snapInterval = 0.025;
slider.value = 0.8;
slider.rotation += -90;
slider.x = i * 40 + 25;
container.addChild(slider);
sliders.push(slider);
var line:Shape = new Shape();
line.graphics.lineStyle(1, 0x888888);
line.graphics.drawRect(i * 40 + 14, 0, 5, -80);
line.graphics.endFill();
container.addChild(line);
var shape:Shape = new Shape();
shape.graphics.beginFill(0x00cc00);
shape.graphics.drawRect(i * 40 + 15, 0, 3, -80);
shape.graphics.endFill();
container.addChild(shape);
graph.push(shape);
}
playback.addEventListener(SampleDataEvent.SAMPLE_DATA, onSoundData);
playback.play();
}
private function onSoundData(event:SampleDataEvent):void {
for(var i:int = 0; i < sound.length; i++){
bytes[i] = new ByteArray();
bytes[i].length = BUFFER_SIZE * 4 * 2;
sound[i].extract(bytes[i], BUFFER_SIZE);
var volume:Number = 0;
bytes[i].position = 0;
for(var j:int = 0; j < BUFFER_SIZE; j++){
volume += Math.abs(bytes[i].readFloat());
volume += Math.abs(bytes[i].readFloat());
}
volume = (volume / (BUFFER_SIZE * .5)) * sliders[i].value;
shader.data['track' + (i + 1)].width = BUFFER_SIZE / 1024;
shader.data['track' + (i + 1)].height = 512;
shader.data['track' + (i + 1)].input = bytes[i];
shader.data['vol' + (i + 1)].value = [sliders[i].value];
graph[i].scaleY = volume;
}
var shaderJob:ShaderJob = new ShaderJob(shader,event.data,BUFFER_SIZE / 1024,512);
shaderJob.start(true);
var shaderJob2:ShaderJob = new ShaderJob(shader,recBA,BUFFER_SIZE / 1024,512);
shaderJob2.start(true);
}
}
}

Answer 1

You can tell when a shader has completed it's job using the ShaderEvent.COMPLETE listener. Like so:
shaderJob.addEventListener(ShaderEvent.COMPLETE, onShaderComplete);
private function onShaderComplete(e:Event):void
{
//Do Something here
}
See this link for more details.
One thing about your code though. You're doing this shader job inside of a sampleDataEvent and I can see this being problematic (possibly) in the sense that your mixing may be out of sync with your playback (that is, if you plan on mixing live and writing the mixed data back into the sound stream). Anyway that's perhaps an issue for a new question. This should solve your problem with needing to know when the mixing is complete.
Note you also need to add "false" to the shaderJob.start(false) function. From the documentation about the ShaderEvent.COMPLETE:
"Dispatched when a ShaderJob that executes asynchronously finishes processing the data using the shader. A ShaderJob instance executes asynchronously when the start() method is called with a false value for the waitForCompletion parameter."
Update
In response to your inquiry about how to only process inside the sampleDataEvent if the sound isnt being processed:
private var isProcessing:Boolean = false;
private function onSoundData(event:SampleDataEvent):void {
if(isProcessing != true){
for(var i:int = 0; i < sound.length; i++){
bytes[i] = new ByteArray();
bytes[i].length = BUFFER_SIZE * 4 * 2;
sound[i].extract(bytes[i], BUFFER_SIZE);
var volume:Number = 0;
bytes[i].position = 0;
for(var j:int = 0; j < BUFFER_SIZE; j++){
volume += Math.abs(bytes[i].readFloat());
volume += Math.abs(bytes[i].readFloat());
}
volume = (volume / (BUFFER_SIZE * .5)) * sliders[i].value;
shader.data['track' + (i + 1)].width = BUFFER_SIZE / 1024;
shader.data['track' + (i + 1)].height = 512;
shader.data['track' + (i + 1)].input = bytes[i];
shader.data['vol' + (i + 1)].value = [sliders[i].value];
graph[i].scaleY = volume;
}
var shaderJob:ShaderJob = new ShaderJob(shader,event.data,BUFFER_SIZE / 1024,512);
shaderJob.start(false);
shaderJob.addEventListener(ShaderEvent.COMPLETE, onShaderComplete);
var shaderJob2:ShaderJob = new ShaderJob(shader,recBA,BUFFER_SIZE / 1024,512);
shaderJob2.start(false);
}
}
private function onShaderComplete(e:ShaderEvent):void
{
//Do something here
isProcessing = false;
}