Basic.as

package {
 
	import flash.display.Shape;
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.SampleDataEvent;
	import flash.media.Microphone;
	import flash.media.Sound;
	import flash.media.SoundMixer;
	import flash.utils.ByteArray;
 
	/**
	 * Simple Microphone test for Flash Player 10.1
	 * @author Devon O.
	 */
 
	[SWF(width='550', height='450', backgroundColor='#000000', frameRate='40')]
	public class Basic extends Sprite {
 
		// sound
		private var _soundBytes:ByteArray = new ByteArray();
		private var _micBytes:ByteArray;
		private var _micSound:Sound;
		private var _lines:Vector.<Shape> = new Vector.<Shape>(512, true);
 
		private var _ctr:int;
 
		public function Basic():void {
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
 
		private function init(event:Event = null):void {
			removeEventListener(Event.ADDED_TO_STAGE, init);
 
			initEqualizer();
			initMic();
			initSound();
 
			addEventListener(Event.ENTER_FRAME, drawLines);
		}
 
		private function initEqualizer():void {
			var holder:Sprite = new Sprite();
			for (var i:int = 0; i < 512; i++) {
				var line:Shape = new Shape();
				with(line.graphics) {
					beginFill(0xFFFFFF);
					drawRect(0, -300, 1, 300);
					endFill();
				}
				line.x = i;
				line.scaleY = 0;
				holder.addChild(line);
				_lines[i] = line;
			}
			holder.y = 400;
			holder.x = stage.stageWidth * .5 - holder.width * .5;
			addChild(holder);
		}		
 
		private function initMic():void {
			var mic:Microphone = Microphone.getMicrophone();
            if ( mic ) {
                mic.setLoopBack(false);
                mic.rate = 44;
		mic.gain = 60;
                mic.addEventListener(SampleDataEvent.SAMPLE_DATA, micSampleDataHandler);
            }
            else {
               // no mic
            }
		}
 
		private function micSampleDataHandler(event:SampleDataEvent) :void {
            _micBytes = event.data;
			_micSound.play();
        }
 
		private function initSound():void {
			_micSound = new Sound();
			_micSound.addEventListener(SampleDataEvent.SAMPLE_DATA, soundSampleDataHandler);
		}
 
		private function soundSampleDataHandler(event:SampleDataEvent):void {
			for (var i:int = 0; i < 8192 && _micBytes.bytesAvailable > 0; i++) {
				var sample:Number = _micBytes.readFloat();
				event.data.writeFloat(sample);
				event.data.writeFloat(sample);
			}
		}
 
		private function drawLines(event:Event):void {
			SoundMixer.computeSpectrum(_soundBytes, true);
			if (_soundBytes.bytesAvailable) {
				_ctr = 0;
				while (++_ctr < 512) {
					_lines[_ctr].scaleY = _soundBytes.readFloat();
				}
			}
		}
	}
}