793 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
			
		
		
	
	
			793 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
| (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);throw new Error("Cannot find module '"+o+"'")}var f=n[o]={exports:{}};t[o][0].call(f.exports,function(e){var n=t[o][1][e];return s(n?n:e)},f,f.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
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| exports.FLACDemuxer = require('./src/demuxer');
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| exports.FLACDecoder = require('./src/decoder');
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| require('./src/ogg');
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| 
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| },{"./src/decoder":2,"./src/demuxer":3,"./src/ogg":4}],2:[function(require,module,exports){
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| /*
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|  * FLAC.js - Free Lossless Audio Codec decoder in JavaScript
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|  * Original C version from FFmpeg (c) 2003 Alex Beregszaszi
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|  * JavaScript port by Devon Govett and Jens Nockert of Official.fm Labs
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|  * 
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|  * Licensed under the same terms as the original.  The original
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|  * license follows.
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|  *
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|  * FLAC.js is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FLAC.js is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  */
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| 
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| var AV = (window.AV);
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| 
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| var FLACDecoder = AV.Decoder.extend(function() {
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|     AV.Decoder.register('flac', this);
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|     
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|     this.prototype.setCookie = function(cookie) {
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|         this.cookie = cookie;
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|         
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|         // initialize arrays
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|         this.decoded = [];
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|         for (var i = 0; i < this.format.channelsPerFrame; i++) {
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|             this.decoded[i] = new Int32Array(cookie.maxBlockSize);
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|         }
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|         
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|         // for 24 bit lpc frames, this is used to simulate a 64 bit int
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|         this.lpc_total = new Int32Array(2);
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|     };
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|     
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|     const BLOCK_SIZES = new Int16Array([
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|                0,      192, 576 << 0, 576 << 1, 576 << 2, 576 << 3,        0,        0,
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|         256 << 0, 256 << 1, 256 << 2, 256 << 3, 256 << 4, 256 << 5, 256 << 6, 256 << 7
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|     ]);
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|     
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|     const SAMPLE_RATES = new Int32Array([
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|         0, 88200, 176400, 192000,
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|         8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
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|         0, 0, 0, 0
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|     ]);
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|     
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|     const SAMPLE_SIZES = new Int8Array([
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|         0, 8, 12, 0, 16, 20, 24, 0
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|     ]);
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|     
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|     const MAX_CHANNELS = 8,
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|           CHMODE_INDEPENDENT = 0,
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|           CHMODE_LEFT_SIDE = 8,
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|           CHMODE_RIGHT_SIDE = 9,
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|           CHMODE_MID_SIDE = 10;
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|     
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|     this.prototype.readChunk = function() {
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|         var stream = this.bitstream;
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|         if (!stream.available(32))
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|             return;
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|                             
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|         // frame sync code
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|         if ((stream.read(15) & 0x7FFF) !== 0x7FFC)
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|             throw new Error('Invalid sync code');
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|             
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|         var isVarSize = stream.read(1),  // variable block size stream code
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|             bsCode = stream.read(4),  // block size
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|             srCode = stream.read(4),  // sample rate code
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|             chMode = stream.read(4),  // channel mode
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|             bpsCode = stream.read(3); // bits per sample
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|             
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|         stream.advance(1); // reserved bit
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|         
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|         // channels
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|         this.chMode = chMode;
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|         var channels;
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|         
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|         if (chMode < MAX_CHANNELS) {
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|             channels = chMode + 1;
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|             this.chMode = CHMODE_INDEPENDENT;
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|         } else if (chMode <= CHMODE_MID_SIDE) {
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|             channels = 2;
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|         } else {
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|             throw new Error('Invalid channel mode');
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|         }
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|         
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|         if (channels !== this.format.channelsPerFrame)
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|             throw new Error('Switching channel layout mid-stream not supported.');
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|         
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|         // bits per sample    
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|         if (bpsCode === 3 || bpsCode === 7)
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|             throw new Error('Invalid sample size code');
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|             
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|         this.bps = SAMPLE_SIZES[bpsCode];
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|         if (this.bps !== this.format.bitsPerChannel)
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|             throw new Error('Switching bits per sample mid-stream not supported.');
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|         
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|         // sample number or frame number
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|         // see http://www.hydrogenaudio.org/forums/index.php?s=ea7085ffe6d57132c36e6105c0d434c9&showtopic=88390&pid=754269&st=0&#entry754269
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|         var ones = 0;
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|         while (stream.read(1) === 1)
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|             ones++;
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|         
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|         var frame_or_sample_num = stream.read(7 - ones);
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|         for (; ones > 1; ones--) {
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|             stream.advance(2); // == 2
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|             frame_or_sample_num = (frame_or_sample_num << 6) | stream.read(6);
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|         }
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|                 
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|         // block size
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|         if (bsCode === 0)
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|             throw new Error('Reserved blocksize code');
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|         else if (bsCode === 6)
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|             this.blockSize = stream.read(8) + 1;
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|         else if (bsCode === 7)
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|             this.blockSize = stream.read(16) + 1;
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|         else
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|             this.blockSize = BLOCK_SIZES[bsCode];
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|             
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|         // sample rate
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|         var sampleRate;
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|         if (srCode < 12)
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|             sampleRate = SAMPLE_RATES[srCode];
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|         else if (srCode === 12)
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|             sampleRate = stream.read(8) * 1000;
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|         else if (srCode === 13)
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|             sampleRate = stream.read(16);
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|         else if (srCode === 14)
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|             sampleRate = stream.read(16) * 10;
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|         else
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|             throw new Error('Invalid sample rate code');
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|             
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|         stream.advance(8); // skip CRC check
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|         
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|         // subframes
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|         for (var i = 0; i < channels; i++)
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|             this.decodeSubframe(i);
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|         
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|         stream.align();
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|         stream.advance(16); // skip CRC frame footer
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|         
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|         var is32 = this.bps > 16,
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|             output = new ArrayBuffer(this.blockSize * channels * (is32 ? 4 : 2)),
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|             buf = is32 ? new Int32Array(output) : new Int16Array(output),
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|             blockSize = this.blockSize,
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|             decoded = this.decoded,
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|             j = 0;
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|             
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|         switch (this.chMode) {
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|             case CHMODE_INDEPENDENT:
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|                 for (var k = 0; k < blockSize; k++) {
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|                     for (var i = 0; i < channels; i++) {
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|                         buf[j++] = decoded[i][k];
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|                     }
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|                 }
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|                 break;
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|                 
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|             case CHMODE_LEFT_SIDE:
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|                 for (var i = 0; i < blockSize; i++) {
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|                     var left = decoded[0][i],
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|                         right = decoded[1][i];
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| 
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|                     buf[j++] = left;
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|                     buf[j++] = (left - right);
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|                 }
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|                 break;
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|                 
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|             case CHMODE_RIGHT_SIDE:
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|                 for (var i = 0; i < blockSize; i++) {
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|                     var left = decoded[0][i],
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|                         right = decoded[1][i];
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| 
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|                     buf[j++] = (left + right);
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|                     buf[j++] = right;
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|                 }
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|                 break;
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|                 
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|             case CHMODE_MID_SIDE:
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|                 for (var i = 0; i < blockSize; i++) {
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|                     var left = decoded[0][i],
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|                         right = decoded[1][i];
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|                     
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|                     left -= right >> 1;
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|                     buf[j++] = (left + right);
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|                     buf[j++] = left;
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|                 }
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|                 break;
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|         }
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|         
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|         return buf;
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|     };
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|     
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|     this.prototype.decodeSubframe = function(channel) {
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|         var wasted = 0,
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|             stream = this.bitstream,
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|             blockSize = this.blockSize,
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|             decoded = this.decoded;
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|         
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|         this.curr_bps = this.bps;
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|         if (channel === 0) {
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|             if (this.chMode === CHMODE_RIGHT_SIDE)
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|                 this.curr_bps++;
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|         } else {
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|             if (this.chMode === CHMODE_LEFT_SIDE || this.chMode === CHMODE_MID_SIDE)
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|                 this.curr_bps++;
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|         }
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|         
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|         if (stream.read(1))
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|             throw new Error("Invalid subframe padding");
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|         
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|         var type = stream.read(6);
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|         
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|         if (stream.read(1)) {
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|             wasted = 1;
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|             while (!stream.read(1))
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|                 wasted++;
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| 
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|             this.curr_bps -= wasted;
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|         }
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|         
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|         if (this.curr_bps > 32)
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|             throw new Error("decorrelated bit depth > 32 (" + this.curr_bps + ")");
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|         
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|         if (type === 0) {
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|             var tmp = stream.read(this.curr_bps, true);
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|             for (var i = 0; i < blockSize; i++)
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|                 decoded[channel][i] = tmp;
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|                 
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|         } else if (type === 1) {
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|             var bps = this.curr_bps;
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|             for (var i = 0; i < blockSize; i++)
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|                 decoded[channel][i] = stream.read(bps, true);
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|                 
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|         } else if ((type >= 8) && (type <= 12)) {
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|             this.decode_subframe_fixed(channel, type & ~0x8);
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|                 
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|         } else if (type >= 32) {
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|             this.decode_subframe_lpc(channel, (type & ~0x20) + 1);
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| 
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|         } else {
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|             throw new Error("Invalid coding type");
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|         }
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|         
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|         if (wasted) {
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|             for (var i = 0; i < blockSize; i++)
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|                 decoded[channel][i] <<= wasted;
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|         }
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|     };
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|     
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|     this.prototype.decode_subframe_fixed = function(channel, predictor_order) {
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|         var decoded = this.decoded[channel],
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|             stream = this.bitstream,
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|             bps = this.curr_bps;
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|     
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|         // warm up samples
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|         for (var i = 0; i < predictor_order; i++)
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|             decoded[i] = stream.read(bps, true);
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|     
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|         this.decode_residuals(channel, predictor_order);
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|         
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|         var a = 0, b = 0, c = 0, d = 0;
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|         
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|         if (predictor_order > 0) 
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|             a = decoded[predictor_order - 1];
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|         
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|         if (predictor_order > 1)
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|             b = a - decoded[predictor_order - 2];
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|         
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|         if (predictor_order > 2) 
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|             c = b - decoded[predictor_order - 2] + decoded[predictor_order - 3];
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|         
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|         if (predictor_order > 3)
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|             d = c - decoded[predictor_order - 2] + 2 * decoded[predictor_order - 3] - decoded[predictor_order - 4];
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|             
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|         switch (predictor_order) {
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|             case 0:
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|                 break;
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|                 
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|             case 1:
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|             case 2:
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|             case 3:
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|             case 4:
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|                 var abcd = new Int32Array([a, b, c, d]),
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|                     blockSize = this.blockSize;
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|                     
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|                 for (var i = predictor_order; i < blockSize; i++) {
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|                     abcd[predictor_order - 1] += decoded[i];
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|                     
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|                     for (var j = predictor_order - 2; j >= 0; j--) {
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|                         abcd[j] += abcd[j + 1];
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|                     }
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|                     
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|                     decoded[i] = abcd[0];
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|                 }
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|                 
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|                 break;
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|                 
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|             default:
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|                 throw new Error("Invalid Predictor Order " + predictor_order);
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|         }
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|     };
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|     
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|     this.prototype.decode_subframe_lpc = function(channel, predictor_order) {
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|         var stream = this.bitstream,
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|             decoded = this.decoded[channel],
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|             bps = this.curr_bps,
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|             blockSize = this.blockSize;
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|             
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|         // warm up samples
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|         for (var i = 0; i < predictor_order; i++) {
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|             decoded[i] = stream.read(bps, true);
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|         }
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| 
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|         var coeff_prec = stream.read(4) + 1;
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|         if (coeff_prec === 16)
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|             throw new Error("Invalid coefficient precision");
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|         
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|         var qlevel = stream.read(5, true);
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|         if (qlevel < 0)
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|             throw new Error("Negative qlevel, maybe buggy stream");
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|         
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|         var coeffs = new Int32Array(32);
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|         for (var i = 0; i < predictor_order; i++) {
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|             coeffs[i] = stream.read(coeff_prec, true);
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|         }
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|         
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|         this.decode_residuals(channel, predictor_order);
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|         
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|         if (this.bps <= 16) {
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|             for (var i = predictor_order; i < blockSize - 1; i += 2) {
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|                 var d = decoded[i - predictor_order],
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|                     s0 = 0, s1 = 0, c = 0;
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|             
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|                 for (var j = predictor_order - 1; j > 0; j--) {
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|                     c = coeffs[j];
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|                     s0 += c * d;
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|                     d = decoded[i - j];
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|                     s1 += c * d;
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|                 }
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|             
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|                 c = coeffs[0];
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|                 s0 += c * d;
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|                 d = decoded[i] += (s0 >> qlevel);
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|                 s1 += c * d;
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|                 decoded[i + 1] += (s1 >> qlevel);
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|             }
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|             
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|             if (i < blockSize) {
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|                 var sum = 0;
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|                 for (var j = 0; j < predictor_order; j++)
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|                     sum += coeffs[j] * decoded[i - j - 1];
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|             
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|                 decoded[i] += (sum >> qlevel);
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|             }
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|         } else {
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|             // simulate 64 bit integer using an array of two 32 bit ints
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|             var total = this.lpc_total;
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|             for (var i = predictor_order; i < blockSize; i++) {
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|                 // reset total to 0
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|                 total[0] = 0;
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|                 total[1] = 0;
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| 
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|                 for (j = 0; j < predictor_order; j++) {
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|                     // simulate `total += coeffs[j] * decoded[i - j - 1]`
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|                     multiply_add(total, coeffs[j], decoded[i - j - 1]);                    
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|                 }
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| 
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|                 // simulate `decoded[i] += total >> qlevel`
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|                 // we know that qlevel < 32 since it is a 5 bit field (see above)
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|                 decoded[i] += (total[0] >>> qlevel) | (total[1] << (32 - qlevel));
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|             }
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|         }
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|     };
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|     
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|     const TWO_PWR_32_DBL = Math.pow(2, 32);
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|         
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|     // performs `total += a * b` on a simulated 64 bit int
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|     // total is an Int32Array(2)
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|     // a and b are JS numbers (32 bit ints)
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|     function multiply_add(total, a, b) {
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|         // multiply a * b (we can use normal JS multiplication for this)
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|         var r = a * b;
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|         var n = r < 0;
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|         if (n)
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|             r = -r;
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|             
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|         var r_low = (r % TWO_PWR_32_DBL) | 0;
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|         var r_high = (r / TWO_PWR_32_DBL) | 0;
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|         if (n) {
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|             r_low = ~r_low + 1;
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|             r_high = ~r_high;
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|         }
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|         
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|         // add result to total
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|         var a48 = total[1] >>> 16;
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|         var a32 = total[1] & 0xFFFF;
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|         var a16 = total[0] >>> 16;
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|         var a00 = total[0] & 0xFFFF;
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| 
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|         var b48 = r_high >>> 16;
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|         var b32 = r_high & 0xFFFF;
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|         var b16 = r_low >>> 16;
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|         var b00 = r_low & 0xFFFF;
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| 
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|         var c48 = 0, c32 = 0, c16 = 0, c00 = 0;
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|         c00 += a00 + b00;
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|         c16 += c00 >>> 16;
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|         c00 &= 0xFFFF;
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|         c16 += a16 + b16;
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|         c32 += c16 >>> 16;
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|         c16 &= 0xFFFF;
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|         c32 += a32 + b32;
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|         c48 += c32 >>> 16;
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|         c32 &= 0xFFFF;
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|         c48 += a48 + b48;
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|         c48 &= 0xFFFF;
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|         
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|         // store result back in total
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|         total[0] = (c16 << 16) | c00;
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|         total[1] = (c48 << 16) | c32;
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|     }
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|      
 | |
|     const INT_MAX = 32767;
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|     
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|     this.prototype.decode_residuals = function(channel, predictor_order) {
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|         var stream = this.bitstream,
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|             method_type = stream.read(2);
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|             
 | |
|         if (method_type > 1)
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|             throw new Error('Illegal residual coding method ' + method_type);
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|         
 | |
|         var rice_order = stream.read(4),
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|             samples = (this.blockSize >>> rice_order);
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|             
 | |
|         if (predictor_order > samples)
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|             throw new Error('Invalid predictor order ' + predictor_order + ' > ' + samples);
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|         
 | |
|         var decoded = this.decoded[channel],
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|             sample = predictor_order, 
 | |
|             i = predictor_order;
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|         
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|         for (var partition = 0; partition < (1 << rice_order); partition++) {
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|             var tmp = stream.read(method_type === 0 ? 4 : 5);
 | |
| 
 | |
|             if (tmp === (method_type === 0 ? 15 : 31)) {
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|                 tmp = stream.read(5);
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|                 for (; i < samples; i++)
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|                     decoded[sample++] = stream.read(tmp, true);
 | |
|                     
 | |
|             } else {
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|                 for (; i < samples; i++)
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|                     decoded[sample++] = this.golomb(tmp, INT_MAX, 0);
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|             }
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|             
 | |
|             i = 0;
 | |
|         }
 | |
|     };
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|     
 | |
|     const MIN_CACHE_BITS = 25;
 | |
|     
 | |
|     this.prototype.golomb = function(k, limit, esc_len) {
 | |
|         var data = this.bitstream,
 | |
|             offset = data.bitPosition,
 | |
|             buf = data.peek(32 - offset) << offset,
 | |
|             v = 0;
 | |
|         
 | |
|         var log = 31 - clz(buf | 1); // log2(buf)
 | |
| 
 | |
|         if (log - k >= 32 - MIN_CACHE_BITS && 32 - log < limit) {
 | |
|             buf >>>= log - k;
 | |
|             buf += (30 - log) << k;
 | |
| 
 | |
|             data.advance(32 + k - log);
 | |
|             v = buf;
 | |
|             
 | |
|         } else {
 | |
|             for (var i = 0; data.read(1) === 0; i++)
 | |
|                 buf = data.peek(32 - offset) << offset;
 | |
| 
 | |
|             if (i < limit - 1) {
 | |
|                 if (k)
 | |
|                     buf = data.read(k);
 | |
|                 else
 | |
|                     buf = 0;
 | |
| 
 | |
|                 v = buf + (i << k);
 | |
|                 
 | |
|             } else if (i === limit - 1) {
 | |
|                 buf = data.read(esc_len);
 | |
|                 v = buf + 1;
 | |
|                 
 | |
|             } else {
 | |
|                 v = -1;
 | |
|             }
 | |
|         }
 | |
|         
 | |
|         return (v >> 1) ^ -(v & 1);
 | |
|     };
 | |
|     
 | |
|     // Should be in the damned standard library...
 | |
|     function clz(input) {
 | |
|         var output = 0,
 | |
|             curbyte = 0;
 | |
| 
 | |
|         while(true) { // emulate goto in JS using the break statement :D
 | |
|             curbyte = input >>> 24;
 | |
|             if (curbyte) break;
 | |
|             output += 8;
 | |
| 
 | |
|             curbyte = input >>> 16;
 | |
|             if (curbyte & 0xff) break;
 | |
|             output += 8;
 | |
| 
 | |
|             curbyte = input >>> 8;
 | |
|             if (curbyte & 0xff) break;
 | |
|             output += 8;
 | |
| 
 | |
|             curbyte = input;
 | |
|             if (curbyte & 0xff) break;
 | |
|             output += 8;
 | |
| 
 | |
|             return output;
 | |
|         }
 | |
| 
 | |
|         if (!(curbyte & 0xf0))
 | |
|             output += 4;
 | |
|         else
 | |
|             curbyte >>>= 4;
 | |
| 
 | |
|         if (curbyte & 0x8)
 | |
|             return output;
 | |
|             
 | |
|         if (curbyte & 0x4)
 | |
|             return output + 1;
 | |
|             
 | |
|         if (curbyte & 0x2)
 | |
|             return output + 2;
 | |
|             
 | |
|         if (curbyte & 0x1)
 | |
|             return output + 3;
 | |
| 
 | |
|         // shouldn't get here
 | |
|         return output + 4;
 | |
|     }
 | |
| });
 | |
| 
 | |
| module.exports = FLACDecoder;
 | |
| 
 | |
| },{}],3:[function(require,module,exports){
 | |
| /*
 | |
|  * FLAC.js - Free Lossless Audio Codec decoder in JavaScript
 | |
|  * By Devon Govett and Jens Nockert of Official.fm Labs
 | |
|  *
 | |
|  * FLAC.js is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU Lesser General Public
 | |
|  * License as published by the Free Software Foundation; either
 | |
|  * version 2.1 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  * FLAC.js is distributed in the hope that it will be useful,
 | |
|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | |
|  * Lesser General Public License for more details.
 | |
|  *
 | |
|  */
 | |
| 
 | |
| var AV = (window.AV);
 | |
| 
 | |
| var FLACDemuxer = AV.Demuxer.extend(function() {
 | |
|     AV.Demuxer.register(this);
 | |
|     
 | |
|     this.probe = function(buffer) {
 | |
|         return buffer.peekString(0, 4) === 'fLaC';
 | |
|     }
 | |
|     
 | |
|     const STREAMINFO = 0,
 | |
|           PADDING = 1,
 | |
|           APPLICATION = 2,
 | |
|           SEEKTABLE = 3,
 | |
|           VORBIS_COMMENT = 4,
 | |
|           CUESHEET = 5,
 | |
|           PICTURE = 6,
 | |
|           INVALID = 127,
 | |
|           STREAMINFO_SIZE = 34;
 | |
|     
 | |
|     this.prototype.readChunk = function() {
 | |
|         var stream = this.stream;
 | |
|         
 | |
|         if (!this.readHeader && stream.available(4)) {
 | |
|             if (stream.readString(4) !== 'fLaC')
 | |
|                 return this.emit('error', 'Invalid FLAC file.');
 | |
|                 
 | |
|             this.readHeader = true;
 | |
|         }
 | |
|         
 | |
|         while (stream.available(1) && !this.last) {                     
 | |
|             if (!this.readBlockHeaders) {
 | |
|                 var tmp = stream.readUInt8();
 | |
|                 this.last = (tmp & 0x80) === 0x80,
 | |
|                 this.type = tmp & 0x7F,
 | |
|                 this.size = stream.readUInt24();
 | |
|             }
 | |
|             
 | |
|             if (!this.foundStreamInfo && this.type !== STREAMINFO)
 | |
|                 return this.emit('error', 'STREAMINFO must be the first block');
 | |
|                 
 | |
|             if (!stream.available(this.size))
 | |
|                 return;
 | |
|             
 | |
|             switch (this.type) {
 | |
|                 case STREAMINFO:
 | |
|                     if (this.foundStreamInfo)
 | |
|                         return this.emit('error', 'STREAMINFO can only occur once.');
 | |
|                     
 | |
|                     if (this.size !== STREAMINFO_SIZE)
 | |
|                         return this.emit('error', 'STREAMINFO size is wrong.');
 | |
|                     
 | |
|                     this.foundStreamInfo = true;
 | |
|                     var bitstream = new AV.Bitstream(stream);
 | |
|                 
 | |
|                     var cookie = {
 | |
|                         minBlockSize: bitstream.read(16),
 | |
|                         maxBlockSize: bitstream.read(16),
 | |
|                         minFrameSize: bitstream.read(24),
 | |
|                         maxFrameSize: bitstream.read(24)
 | |
|                     };
 | |
|                 
 | |
|                     this.format = {
 | |
|                         formatID: 'flac',
 | |
|                         sampleRate: bitstream.read(20),
 | |
|                         channelsPerFrame: bitstream.read(3) + 1,
 | |
|                         bitsPerChannel: bitstream.read(5) + 1
 | |
|                     };
 | |
|                 
 | |
|                     this.emit('format', this.format);
 | |
|                     this.emit('cookie', cookie);
 | |
|                 
 | |
|                     var sampleCount = bitstream.read(36);
 | |
|                     this.emit('duration', sampleCount / this.format.sampleRate * 1000 | 0);
 | |
|                 
 | |
|                     stream.advance(16); // skip MD5 hashes
 | |
|                     this.readBlockHeaders = false;
 | |
|                     break;
 | |
| 
 | |
|                     /*
 | |
|                     I am only looking at the least significant 32 bits of sample number and offset data
 | |
|                     This is more than sufficient for the longest flac file I have (~50 mins 2-channel 16-bit 44.1k which uses about 7.5% of the UInt32 space for the largest offset)
 | |
|                     Can certainly be improved by storing sample numbers and offests as doubles, but would require additional overriding of the searchTimestamp and seek functions (possibly more?)
 | |
|                     Also the flac faq suggests it would be possible to find frame lengths and thus create seek points on the fly via decoding but I assume this would be slow
 | |
|                     I may look into these thigns though as my project progresses
 | |
|                     */
 | |
|                     case SEEKTABLE:
 | |
|                         for(var s=0; s<this.size/18; s++)
 | |
|                         {
 | |
|                             if(stream.peekUInt32(0) == 0xFFFFFFFF && stream.peekUInt32(1) == 0xFFFFFFFF)
 | |
|                             {
 | |
|                                 //placeholder, ignore
 | |
|                                 stream.advance(18);
 | |
|                             } else {
 | |
|                                 if(stream.readUInt32() > 0)
 | |
|                                 {
 | |
|                                     this.emit('error', 'Seek points with sample number >UInt32 not supported');
 | |
|                                 }
 | |
|                                 var samplenum = stream.readUInt32();
 | |
|                                 if(stream.readUInt32() > 0)
 | |
|                                 {
 | |
|                                     this.emit('error', 'Seek points with stream offset >UInt32 not supported');
 | |
|                                 }
 | |
|                                 var offset = stream.readUInt32();
 | |
| 
 | |
|                                 stream.advance(2);
 | |
| 
 | |
|                                 this.addSeekPoint(offset, samplenum);
 | |
|                             }
 | |
|                         }
 | |
|                         break;
 | |
| 
 | |
|                 case VORBIS_COMMENT:
 | |
|                     // see http://www.xiph.org/vorbis/doc/v-comment.html
 | |
|                     this.metadata || (this.metadata = {});
 | |
|                     var len = stream.readUInt32(true);
 | |
|                     
 | |
|                     this.metadata.vendor = stream.readString(len);
 | |
|                     var length = stream.readUInt32(true);
 | |
|                     
 | |
|                     for (var i = 0; i < length; i++) {
 | |
|                         len = stream.readUInt32(true);
 | |
|                         var str = stream.readString(len, 'utf8'),
 | |
|                             idx = str.indexOf('=');
 | |
|                             
 | |
|                         this.metadata[str.slice(0, idx).toLowerCase()] = str.slice(idx + 1);
 | |
|                     }
 | |
|                     
 | |
|                     // TODO: standardize field names across formats
 | |
|                     break;
 | |
|                     
 | |
|                 case PICTURE:
 | |
|                     var type = stream.readUInt32();
 | |
|                     if (type !== 3) { // make sure this is album art (type 3)
 | |
|                         stream.advance(this.size - 4);
 | |
|                     } else {
 | |
|                         var mimeLen = stream.readUInt32(),
 | |
|                             mime = stream.readString(mimeLen),
 | |
|                             descLen = stream.readUInt32(),
 | |
|                             description = stream.readString(descLen),
 | |
|                             width = stream.readUInt32(),
 | |
|                             height = stream.readUInt32(),
 | |
|                             depth = stream.readUInt32(),
 | |
|                             colors = stream.readUInt32(),
 | |
|                             length = stream.readUInt32(),
 | |
|                             picture = stream.readBuffer(length);
 | |
|                     
 | |
|                         this.metadata || (this.metadata = {});
 | |
|                         this.metadata.coverArt = picture;
 | |
|                     }
 | |
|                     
 | |
|                     // does anyone want the rest of the info?
 | |
|                     break;
 | |
|                 
 | |
|                 default:
 | |
|                     stream.advance(this.size);
 | |
|                     this.readBlockHeaders = false;
 | |
|             }
 | |
|             
 | |
|             if (this.last && this.metadata)
 | |
|                 this.emit('metadata', this.metadata);
 | |
|         }
 | |
|         
 | |
|         while (stream.available(1) && this.last) {
 | |
|             var buffer = stream.readSingleBuffer(stream.remainingBytes());
 | |
|             this.emit('data', buffer);
 | |
|         }
 | |
|     }
 | |
|     
 | |
| });
 | |
| 
 | |
| module.exports = FLACDemuxer;
 | |
| 
 | |
| },{}],4:[function(require,module,exports){
 | |
| var AV = (window.AV);
 | |
| 
 | |
| // if ogg.js exists, register a plugin
 | |
| try {
 | |
|   var OggDemuxer = (window.AV.OggDemuxer);
 | |
| } catch (e) {};
 | |
| if (!OggDemuxer) return;
 | |
| 
 | |
| OggDemuxer.plugins.push({
 | |
|   magic: "\177FLAC",
 | |
|   
 | |
|   init: function() {
 | |
|     this.list = new AV.BufferList();
 | |
|     this.stream = new AV.Stream(this.list);
 | |
|   },
 | |
|   
 | |
|   readHeaders: function(packet) {
 | |
|     var stream = this.stream;
 | |
|     this.list.append(new AV.Buffer(packet));
 | |
|     
 | |
|     stream.advance(5); // magic
 | |
|     if (stream.readUInt8() != 1)
 | |
|       throw new Error('Unsupported FLAC version');
 | |
|       
 | |
|     stream.advance(3);
 | |
|     if (stream.peekString(0, 4) != 'fLaC')
 | |
|       throw new Error('Not flac');
 | |
|       
 | |
|     this.flac = AV.Demuxer.find(stream.peekSingleBuffer(0, stream.remainingBytes()));
 | |
|     if (!this.flac)
 | |
|       throw new Error('Flac demuxer not found');
 | |
|     
 | |
|     this.flac.prototype.readChunk.call(this);
 | |
|     return true;
 | |
|   },
 | |
|   
 | |
|   readPacket: function(packet) {
 | |
|     this.list.append(new AV.Buffer(packet));
 | |
|     this.flac.prototype.readChunk.call(this);
 | |
|   }
 | |
| });
 | |
| 
 | |
| },{}]},{},[1])
 | |
| 
 | |
| 
 | |
| //# sourceMappingURL=flac.js.map
 |