/flash/flash-audio/src/com/ryanberdeen/audio/SoundSampleSource.as

 1/*
 2 * Copyright 2009 Ryan Berdeen. All rights reserved.
 3 * Distributed under the terms of the MIT License.
 4 * See accompanying file LICENSE.txt
 5 */
 6
 7package com.ryanberdeen.audio {
 8  import flash.media.Sound;
 9  import flash.utils.ByteArray;
10
11  /**
12  * <code>ISampleSource</code> that provides samples unaltered from a
13  * <code>Sound</code>.
14  */
15  public class SoundSampleSource implements ISampleSource {
16    private var sound:Sound;
17    private var startPosition:Number;
18    private var _length:Number;
19
20    public function SoundSampleSource(sound:Sound):void {
21      this.sound = sound;
22      startPosition = 0;
23      _length = Math.ceil(sound.length * 44.1);
24    }
25
26    public function extract(target:ByteArray, length:Number, startPosition:Number = -1):Number {
27      if (startPosition == -1) {
28        startPosition = this.startPosition;
29      }
30      var result:Number = sound.extract(target, length, startPosition);
31      this.startPosition = startPosition + length;
32      return result;
33    }
34
35    public function toSourcePosition(position:Number):Number {
36      return position;
37    }
38
39    public function get length():Number {
40      return _length;
41    }
42  }
43}