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@ronag
Created November 4, 2014 14:52
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"use strict";
// jsmpeg by Dominic Szablewski - phoboslab.org, github.com/phoboslab
//
// Consider this to be under MIT license. It's largely based an an Open Source
// Decoder for Java under GPL, while I looked at another Decoder from Nokia
// (under no particular license?) for certain aspects.
// I'm not sure if this work is "derivative" enough to have a different license
// but then again, who still cares about MPEG1?
//
// Based on "Java MPEG-1 Video Decoder and Player" by Korandi Zoltan:
// http://sourceforge.net/projects/javampeg1video/
//
// Inspired by "MPEG Decoder in Java ME" by Nokia:
// http://www.developer.nokia.com/Community/Wiki/MPEG_decoder_in_Java_ME
var decoder = null;
var _buffers = [];
onmessage = function(event) {
switch (event.data.type) {
case 'open':
decoder = new jsmpeg(event.data.url);
break;
case 'close':
decoder.close();
break;
case 'buffer':
_buffers.push(event.data.buffer);
break;
}
}
var requestAnimFrame = function(callback){
//return window.requestAnimationFrame ||
// window.webkitRequestAnimationFrame ||
// window.mozRequestAnimationFrame ||
// function( callback ){
// window.setTimeout(callback, 1000 / 60);
// };
//function( callback ){
// setTimeout(callback, 1);//1000 / 60);
//};
setTimeout(callback, 1);
};
var jsmpeg = function( url, opts ) {
opts = opts || {};
this.benchmark = !!opts.benchmark;
this.autoplay = !!opts.autoplay;
this.loop = !!opts.loop;
this.externalLoadCallback = opts.onload || null;
this.externalDecodeCallback = opts.ondecodeframe || null;
this.externalFinishedCallback = opts.onfinished || null;
this.bwFilter = opts.bwFilter || false;
this.customIntraQuantMatrix = new Uint8Array(64);
this.customNonIntraQuantMatrix = new Uint8Array(64);
this.blockData = new Int32Array(64);
this.zeroBlockData = new Int32Array(64);
this.fillArray(this.zeroBlockData, 0);
this.client = new WebSocket(url);
this.client.onopen = this.initSocketClient.bind(this);
};
jsmpeg.prototype.close = function() {
this.client.close();
}
// ----------------------------------------------------------------------------
// Streaming over WebSockets
jsmpeg.prototype.waitForIntraFrame = true;
jsmpeg.prototype.socketBufferSize = 512 * 1024; // 512kb each
jsmpeg.prototype.onlostconnection = null;
jsmpeg.prototype.initSocketClient = function( client ) {
this.buffer = new BitReader(new ArrayBuffer(this.socketBufferSize));
this.nextPictureBuffer = new BitReader(new ArrayBuffer(this.socketBufferSize));
this.nextPictureBuffer.writePos = 0;
this.nextPictureBuffer.chunkBegin = 0;
this.nextPictureBuffer.lastWriteBeforeWrap = 0;
this.client.binaryType = 'arraybuffer';
this.client.onmessage = this.receiveSocketMessage.bind(this);
};
jsmpeg.prototype.decodeSocketHeader = function( data ) {
// Custom header sent to all newly connected clients when streaming
// over websockets:
// struct { char magic[4] = "jsmp"; unsigned short width, height; };
if(
data[0] == SOCKET_MAGIC_BYTES.charCodeAt(0) &&
data[1] == SOCKET_MAGIC_BYTES.charCodeAt(1) &&
data[2] == SOCKET_MAGIC_BYTES.charCodeAt(2) &&
data[3] == SOCKET_MAGIC_BYTES.charCodeAt(3)
) {
this.width = (data[4] * 256 + data[5]);
this.height = (data[6] * 256 + data[7]);
this.initBuffers();
}
};
jsmpeg.prototype.receiveSocketMessage = function( event ) {
var messageData = new Uint8Array(event.data);
if( !this.sequenceStarted ) {
this.decodeSocketHeader(messageData);
}
var current = this.buffer;
var next = this.nextPictureBuffer;
if( next.writePos + messageData.length > next.length ) {
next.lastWriteBeforeWrap = next.writePos;
next.writePos = 0;
next.index = 0;
}
next.bytes.set( messageData, next.writePos );
next.writePos += messageData.length;
var startCode = 0;
while( true ) {
startCode = next.findNextMPEGStartCode();
if(
startCode == BitReader.NOT_FOUND ||
((next.index >> 3) > next.writePos)
) {
// We reached the end with no picture found yet; move back a few bytes
// in case we are at the beginning of a start code and exit.
next.index = Math.max((next.writePos-3), 0) << 3;
return;
}
else if( startCode == START_PICTURE ) {
break;
}
}
// If we are still here, we found the next picture start code!
// Skip picture decoding until we find the first intra frame?
if( this.waitForIntraFrame ) {
next.advance(10); // skip temporalReference
if( next.getBits(3) == PICTURE_TYPE_I ) {
this.waitForIntraFrame = false;
next.chunkBegin = (next.index-13) >> 3;
}
return;
}
// Last picture hasn't been decoded yet? Decode now but skip output
// before scheduling the next one
if( !this.currentPictureDecoded ) {
this.decodePicture(DECODE_SKIP_OUTPUT);
}
// Copy the picture chunk over to 'this.buffer' and schedule decoding.
var chunkEnd = ((next.index) >> 3);
if( chunkEnd > next.chunkBegin ) {
// Just copy the current picture chunk
current.bytes.set( next.bytes.subarray(next.chunkBegin, chunkEnd) );
current.writePos = chunkEnd - next.chunkBegin;
}
else {
// We wrapped the nextPictureBuffer around, so we have to copy the last part
// till the end, as well as from 0 to the current writePos
current.bytes.set( next.bytes.subarray(next.chunkBegin, next.lastWriteBeforeWrap) );
var written = next.lastWriteBeforeWrap - next.chunkBegin;
current.bytes.set( next.bytes.subarray(0, chunkEnd), written );
current.writePos = chunkEnd + written;
}
current.index = 0;
next.chunkBegin = chunkEnd;
// Decode!
this.currentPictureDecoded = false;
requestAnimFrame( this.scheduleDecoding.bind(this));
};
jsmpeg.prototype.scheduleDecoding = function() {
this.decodePicture();
this.currentPictureDecoded = true;
};
// ----------------------------------------------------------------------------
// Recording from WebSockets
jsmpeg.prototype.isRecording = false;
jsmpeg.prototype.recorderWaitForIntraFrame = false;
jsmpeg.prototype.recordedFrames = 0;
jsmpeg.prototype.recordedSize = 0;
jsmpeg.prototype.didStartRecordingCallback = null;
jsmpeg.prototype.recordBuffers = [];
jsmpeg.prototype.canRecord = function(){
return (this.client && this.client.readyState == this.client.OPEN);
};
jsmpeg.prototype.startRecording = function(callback) {
if( !this.canRecord() ) {
return;
}
// Discard old buffers and set for recording
this.discardRecordBuffers();
this.isRecording = true;
this.recorderWaitForIntraFrame = true;
this.didStartRecordingCallback = callback || null;
this.recordedFrames = 0;
this.recordedSize = 0;
// Fudge a simple Sequence Header for the MPEG file
// 3 bytes width & height, 12 bits each
var wh1 = (this.width >> 4),
wh2 = ((this.width & 0xf) << 4) | (this.height >> 8),
wh3 = (this.height & 0xff);
this.recordBuffers.push(new Uint8Array([
0x00, 0x00, 0x01, 0xb3, // Sequence Start Code
wh1, wh2, wh3, // Width & height
0x13, // aspect ratio & framerate
0xff, 0xff, 0xe1, 0x58, // Meh. Bitrate and other boring stuff
0x00, 0x00, 0x01, 0xb8, 0x00, 0x08, 0x00, // GOP
0x00, 0x00, 0x00, 0x01, 0x00 // First Picture Start Code
]));
};
jsmpeg.prototype.recordFrameFromCurrentBuffer = function() {
if( !this.isRecording ) { return; }
if( this.recorderWaitForIntraFrame ) {
// Not an intra frame? Exit.
if( this.pictureCodingType != PICTURE_TYPE_I ) { return; }
// Start recording!
this.recorderWaitForIntraFrame = false;
if( this.didStartRecordingCallback ) {
this.didStartRecordingCallback( this );
}
}
this.recordedFrames++;
this.recordedSize += this.buffer.writePos;
// Copy the actual subrange for the current picture into a new Buffer
this.recordBuffers.push(new Uint8Array(this.buffer.bytes.subarray(0, this.buffer.writePos)));
};
jsmpeg.prototype.discardRecordBuffers = function() {
this.recordBuffers = [];
this.recordedFrames = 0;
};
jsmpeg.prototype.stopRecording = function() {
var blob = new Blob(this.recordBuffers, {type: 'video/mpeg'});
this.discardRecordBuffers();
this.isRecording = false;
return blob;
};
jsmpeg.prototype.play = function(file) {
if( this.playing ) { return; }
this.targetTime = Date.now();
this.playing = true;
this.scheduleNextFrame();
};
jsmpeg.prototype.pause = function(file) {
this.playing = false;
};
jsmpeg.prototype.stop = function(file) {
if( this.buffer ) {
this.buffer.index = this.firstSequenceHeader;
}
this.playing = false;
if( this.client ) {
this.client.close();
this.client = null;
}
};
// ----------------------------------------------------------------------------
// Utilities
jsmpeg.prototype.readCode = function(codeTable) {
var state = 0;
do {
state = codeTable[state + this.buffer.getBits(1)];
} while( state >= 0 && codeTable[state] != 0 );
return codeTable[state+2];
};
jsmpeg.prototype.findStartCode = function( code ) {
var current = 0;
while( true ) {
current = this.buffer.findNextMPEGStartCode();
if( current == code || current == BitReader.NOT_FOUND ) {
return current;
}
}
return BitReader.NOT_FOUND;
};
jsmpeg.prototype.fillArray = function(a, value) {
for( var i = 0, length = a.length; i < length; i++ ) {
a[i] = value;
}
};
jsmpeg.prototype.cachedFrameCount = 0;
jsmpeg.prototype.calculateFrameCount = function() {
if( !this.buffer || this.cachedFrameCount ) {
return this.cachedFrameCount;
}
// Remember the buffer position, so we can rewind to the beginning and
// reset to the current position afterwards
var currentPlaybackIndex = this.buffer.index,
frames = 0;
this.buffer.index = 0;
while( this.findStartCode(START_PICTURE) !== BitReader.NOT_FOUND ) {
frames++;
}
this.buffer.index = currentPlaybackIndex;
this.cachedFrameCount = frames;
return frames;
};
jsmpeg.prototype.calculateDuration = function() {
return this.calculateFrameCount() * (1/this.pictureRate);
};
// ----------------------------------------------------------------------------
// Sequence Layer
jsmpeg.prototype.pictureRate = 30;
jsmpeg.prototype.lateTime = 0;
jsmpeg.prototype.firstSequenceHeader = 0;
jsmpeg.prototype.targetTime = 0;
jsmpeg.prototype.nextFrame = function() {
if( !this.buffer ) { return; }
while(true) {
var code = this.buffer.findNextMPEGStartCode();
if( code == START_SEQUENCE ) {
this.decodeSequenceHeader();
}
else if( code == START_PICTURE ) {
if( this.playing ) {
this.scheduleNextFrame();
}
this.decodePicture();
}
else if( code == BitReader.NOT_FOUND ) {
this.stop(); // Jump back to the beginning
if( this.externalFinishedCallback ) {
this.externalFinishedCallback(this);
}
// Only loop if we found a sequence header
if( this.loop && this.sequenceStarted ) {
this.play();
}
}
else {
// ignore (GROUP, USER_DATA, EXTENSION, SLICES...)
}
}
};
jsmpeg.prototype.scheduleNextFrame = function() {
this.scheduleAnimation();
//this.lateTime = Date.now() - this.targetTime;
//var wait = Math.max(0, (1000/this.pictureRate) - this.lateTime);
//this.targetTime = Date.now() + wait;
//
//if( this.benchmark ) {
// var now = Date.now();
// if(!this.benchframe) {
// this.benchstart = now;
// this.benchframe = 0;
// }
// this.benchframe++;
// var timepassed = now - this.benchstart;
// if( this.benchframe >= 100 ) {
// this.benchfps = (this.benchframe / timepassed) * 1000;
// if( console ) {
// console.log("frames per second: " + this.benchfps);
// }
// this.benchframe = null;
// }
// setTimeout( this.nextFrame.bind(this), 0);
//}
//else if( wait < 18) {
// this.scheduleAnimation();
//}
//else {
// setTimeout( this.scheduleAnimation.bind(this), wait );
//}
};
jsmpeg.prototype.scheduleAnimation = function() {
requestAnimFrame( this.nextFrame.bind(this) );
};
jsmpeg.prototype.decodeSequenceHeader = function() {
this.width = this.buffer.getBits(12);
this.height = this.buffer.getBits(12);
this.buffer.advance(4); // skip pixel aspect ratio
this.pictureRate = PICTURE_RATE[this.buffer.getBits(4)];
this.buffer.advance(18 + 1 + 10 + 1); // skip bitRate, marker, bufferSize and constrained bit
this.initBuffers();
if( this.buffer.getBits(1) ) { // load custom intra quant matrix?
for( var i = 0; i < 64; i++ ) {
this.customIntraQuantMatrix[ZIG_ZAG[i]] = this.buffer.getBits(8);
}
this.intraQuantMatrix = this.customIntraQuantMatrix;
}
if( this.buffer.getBits(1) ) { // load custom non intra quant matrix?
for( var i = 0; i < 64; i++ ) {
this.customNonIntraQuantMatrix[ZIG_ZAG[i]] = this.buffer.getBits(8);
}
this.nonIntraQuantMatrix = this.customNonIntraQuantMatrix;
}
};
jsmpeg.prototype.initBuffers = function() {
this.intraQuantMatrix = DEFAULT_INTRA_QUANT_MATRIX;
this.nonIntraQuantMatrix = DEFAULT_NON_INTRA_QUANT_MATRIX;
this.mbWidth = (this.width + 15) >> 4;
this.mbHeight = (this.height + 15) >> 4;
this.mbSize = this.mbWidth * this.mbHeight;
this.codedWidth = this.mbWidth << 4;
this.codedHeight = this.mbHeight << 4;
this.codedSize = this.codedWidth * this.codedHeight;
this.halfWidth = this.mbWidth << 3;
this.halfHeight = this.mbHeight << 3;
this.quarterSize = this.codedSize >> 2;
// Sequence already started? Don't allocate buffers again
if( this.sequenceStarted ) { return; }
this.sequenceStarted = true;
// Allocated buffers and resize the canvas
this.currentY = new Uint8ClampedArray(this.codedSize);
this.currentY32 = new Uint32Array(this.currentY.buffer);
this.currentCr = new Uint8ClampedArray(this.codedSize >> 2);
this.currentCr32 = new Uint32Array(this.currentCr.buffer);
this.currentCb = new Uint8ClampedArray(this.codedSize >> 2);
this.currentCb32 = new Uint32Array(this.currentCb.buffer);
this.forwardY = new Uint8ClampedArray(this.codedSize);
this.forwardY32 = new Uint32Array(this.forwardY.buffer);
this.forwardCr = new Uint8ClampedArray(this.codedSize >> 2);
this.forwardCr32 = new Uint32Array(this.forwardCr.buffer);
this.forwardCb = new Uint8ClampedArray(this.codedSize >> 2);
this.forwardCb32 = new Uint32Array(this.forwardCb.buffer);
this.currentRGBA = {
width: this.width,
height: this.height
};
for (var n = 0; n < 4; ++n) {
var buffer = new Uint8ClampedArray(this.width * this.height * 4);
this.fillArray(buffer, 255);
_buffers.push(buffer);
}
};
// ----------------------------------------------------------------------------
// Picture Layer
jsmpeg.prototype.currentY = null;
jsmpeg.prototype.currentCr = null;
jsmpeg.prototype.currentCb = null;
jsmpeg.prototype.currentRGBA = null;
jsmpeg.prototype.pictureCodingType = 0;
// Buffers for motion compensation
jsmpeg.prototype.forwardY = null;
jsmpeg.prototype.forwardCr = null;
jsmpeg.prototype.forwardCb = null;
jsmpeg.prototype.fullPelForward = false;
jsmpeg.prototype.forwardFCode = 0;
jsmpeg.prototype.forwardRSize = 0;
jsmpeg.prototype.forwardF = 0;
jsmpeg.prototype.decodePicture = function(skipOutput) {
this.buffer.advance(10); // skip temporalReference
this.pictureCodingType = this.buffer.getBits(3);
this.buffer.advance(16); // skip vbv_delay
// Skip B and D frames or unknown coding type
if( this.pictureCodingType <= 0 || this.pictureCodingType >= PICTURE_TYPE_B ) {
return;
}
// full_pel_forward, forward_f_code
if( this.pictureCodingType == PICTURE_TYPE_P ) {
this.fullPelForward = this.buffer.getBits(1);
this.forwardFCode = this.buffer.getBits(3);
if( this.forwardFCode == 0 ) {
// Ignore picture with zero forward_f_code
return;
}
this.forwardRSize = this.forwardFCode - 1;
this.forwardF = 1 << this.forwardRSize;
}
var code = 0;
do {
code = this.buffer.findNextMPEGStartCode();
} while( code == START_EXTENSION || code == START_USER_DATA );
while( code >= START_SLICE_FIRST && code <= START_SLICE_LAST ) {
this.decodeSlice( (code & 0x000000FF) );
code = this.buffer.findNextMPEGStartCode();
}
// We found the next start code; rewind 32bits and let the main loop handle it.
this.buffer.rewind(32);
// Record this frame, if the recorder wants it
this.recordFrameFromCurrentBuffer();
if (skipOutput != DECODE_SKIP_OUTPUT) {
if (_buffers.length) {
this.currentRGBA.data = _buffers.pop();
this.YCbCrToRGBA();
var data = this.currentRGBA.data;
this.currentRGBA.data = null;
postMessage(data, [data.buffer]);
}
}
// If this is a reference picutre then rotate the prediction pointers
if( this.pictureCodingType == PICTURE_TYPE_I || this.pictureCodingType == PICTURE_TYPE_P ) {
var
tmpY = this.forwardY,
tmpY32 = this.forwardY32,
tmpCr = this.forwardCr,
tmpCr32 = this.forwardCr32,
tmpCb = this.forwardCb,
tmpCb32 = this.forwardCb32;
this.forwardY = this.currentY;
this.forwardY32 = this.currentY32;
this.forwardCr = this.currentCr;
this.forwardCr32 = this.currentCr32;
this.forwardCb = this.currentCb;
this.forwardCb32 = this.currentCb32;
this.currentY = tmpY;
this.currentY32 = tmpY32;
this.currentCr = tmpCr;
this.currentCr32 = tmpCr32;
this.currentCb = tmpCb;
this.currentCb32 = tmpCb32;
}
};
jsmpeg.prototype.YCbCrToRGBA = function() {
var pY = this.currentY;
var pCb = this.currentCb;
var pCr = this.currentCr;
var pRGBA = this.currentRGBA.data;
// Chroma values are the same for each block of 4 pixels, so we proccess
// 2 lines at a time, 2 neighboring pixels each.
// I wish we could use 32bit writes to the RGBA buffer instead of writing
// each byte separately, but we need the automatic clamping of the RGBA
// buffer.
var yIndex1 = 0;
var yIndex2 = this.codedWidth;
var yNext2Lines = this.codedWidth + (this.codedWidth - this.width);
var cIndex = 0;
var cNextLine = this.halfWidth - (this.width >> 1);
var rgbaIndex1 = 0;
var rgbaIndex2 = this.width * 4;
var rgbaNext2Lines = this.width * 4;
var cols = this.width >> 1;
var rows = this.height >> 1;
var y, cb, cr, r, g, b;
for( var row = 0; row < rows; row++ ) {
for( var col = 0; col < cols; col++ ) {
cb = pCb[cIndex];
cr = pCr[cIndex];
cIndex++;
r = (cr + ((cr * 103) >> 8)) - 179;
g = ((cb * 88) >> 8) - 44 + ((cr * 183) >> 8) - 91;
b = (cb + ((cb * 198) >> 8)) - 227;
// Line 1
var y1 = pY[yIndex1++];
var y2 = pY[yIndex1++];
pRGBA[rgbaIndex1] = y1 + r;
pRGBA[rgbaIndex1+1] = y1 - g;
pRGBA[rgbaIndex1+2] = y1 + b;
pRGBA[rgbaIndex1+4] = y2 + r;
pRGBA[rgbaIndex1+5] = y2 - g;
pRGBA[rgbaIndex1+6] = y2 + b;
rgbaIndex1 += 8;
// Line 2
var y3 = pY[yIndex2++];
var y4 = pY[yIndex2++];
pRGBA[rgbaIndex2] = y3 + r;
pRGBA[rgbaIndex2+1] = y3 - g;
pRGBA[rgbaIndex2+2] = y3 + b;
pRGBA[rgbaIndex2+4] = y4 + r;
pRGBA[rgbaIndex2+5] = y4 - g;
pRGBA[rgbaIndex2+6] = y4 + b;
rgbaIndex2 += 8;
}
yIndex1 += yNext2Lines;
yIndex2 += yNext2Lines;
rgbaIndex1 += rgbaNext2Lines;
rgbaIndex2 += rgbaNext2Lines;
cIndex += cNextLine;
}
};
// ----------------------------------------------------------------------------
// Slice Layer
jsmpeg.prototype.quantizerScale = 0;
jsmpeg.prototype.sliceBegin = false;
jsmpeg.prototype.decodeSlice = function(slice) {
this.sliceBegin = true;
this.macroblockAddress = (slice - 1) * this.mbWidth - 1;
// Reset motion vectors and DC predictors
this.motionFwH = this.motionFwHPrev = 0;
this.motionFwV = this.motionFwVPrev = 0;
this.dcPredictorY = 128;
this.dcPredictorCr = 128;
this.dcPredictorCb = 128;
this.quantizerScale = this.buffer.getBits(5);
// skip extra bits
while( this.buffer.getBits(1) ) {
this.buffer.advance(8);
}
do {
this.decodeMacroblock();
// We may have to ignore Video Stream Start Codes here (0xE0)!?
} while( !this.buffer.nextBytesAreStartCode() );
}
// ----------------------------------------------------------------------------
// Macroblock Layer
jsmpeg.prototype.macroblockAddress = 0;
jsmpeg.prototype.mbRow = 0;
jsmpeg.prototype.mbCol = 0;
jsmpeg.prototype.macroblockType = 0;
jsmpeg.prototype.macroblockIntra = false;
jsmpeg.prototype.macroblockMotFw = false;
jsmpeg.prototype.motionFwH = 0;
jsmpeg.prototype.motionFwV = 0;
jsmpeg.prototype.motionFwHPrev = 0;
jsmpeg.prototype.motionFwVPrev = 0;
jsmpeg.prototype.decodeMacroblock = function() {
// Decode macroblock_address_increment
var
increment = 0,
t = this.readCode(MACROBLOCK_ADDRESS_INCREMENT);
while( t == 34 ) {
// macroblock_stuffing
t = this.readCode(MACROBLOCK_ADDRESS_INCREMENT);
}
while( t == 35 ) {
// macroblock_escape
increment += 33;
t = this.readCode(MACROBLOCK_ADDRESS_INCREMENT);
}
increment += t;
// Process any skipped macroblocks
if( this.sliceBegin ) {
// The first macroblock_address_increment of each slice is relative
// to beginning of the preverious row, not the preverious macroblock
this.sliceBegin = false;
this.macroblockAddress += increment;
}
else {
if( this.macroblockAddress + increment >= this.mbSize ) {
// Illegal (too large) macroblock_address_increment
return;
}
if( increment > 1 ) {
// Skipped macroblocks reset DC predictors
this.dcPredictorY = 128;
this.dcPredictorCr = 128;
this.dcPredictorCb = 128;
// Skipped macroblocks in P-pictures reset motion vectors
if( this.pictureCodingType == PICTURE_TYPE_P ) {
this.motionFwH = this.motionFwHPrev = 0;
this.motionFwV = this.motionFwVPrev = 0;
}
}
// Predict skipped macroblocks
while( increment > 1) {
this.macroblockAddress++;
this.mbRow = (this.macroblockAddress / this.mbWidth)|0;
this.mbCol = this.macroblockAddress % this.mbWidth;
this.copyMacroblock(this.motionFwH, this.motionFwV, this.forwardY, this.forwardCr, this.forwardCb);
increment--;
}
this.macroblockAddress++;
}
this.mbRow = (this.macroblockAddress / this.mbWidth)|0;
this.mbCol = this.macroblockAddress % this.mbWidth;
// Process the current macroblock
this.macroblockType = this.readCode(MACROBLOCK_TYPE_TABLES[this.pictureCodingType]);
this.macroblockIntra = (this.macroblockType & 0x01);
this.macroblockMotFw = (this.macroblockType & 0x08);
// Quantizer scale
if( (this.macroblockType & 0x10) != 0 ) {
this.quantizerScale = this.buffer.getBits(5);
}
if( this.macroblockIntra ) {
// Intra-coded macroblocks reset motion vectors
this.motionFwH = this.motionFwHPrev = 0;
this.motionFwV = this.motionFwVPrev = 0;
}
else {
// Non-intra macroblocks reset DC predictors
this.dcPredictorY = 128;
this.dcPredictorCr = 128;
this.dcPredictorCb = 128;
this.decodeMotionVectors();
this.copyMacroblock(this.motionFwH, this.motionFwV, this.forwardY, this.forwardCr, this.forwardCb);
}
// Decode blocks
var cbp = ((this.macroblockType & 0x02) != 0)
? this.readCode(CODE_BLOCK_PATTERN)
: (this.macroblockIntra ? 0x3f : 0);
for( var block = 0, mask = 0x20; block < 6; block++ ) {
if( (cbp & mask) != 0 ) {
this.decodeBlock(block);
}
mask >>= 1;
}
};
jsmpeg.prototype.decodeMotionVectors = function() {
var code, d, r = 0;
// Forward
if( this.macroblockMotFw ) {
// Horizontal forward
code = this.readCode(MOTION);
if( (code != 0) && (this.forwardF != 1) ) {
r = this.buffer.getBits(this.forwardRSize);
d = ((Math.abs(code) - 1) << this.forwardRSize) + r + 1;
if( code < 0 ) {
d = -d;
}
}
else {
d = code;
}
this.motionFwHPrev += d;
if( this.motionFwHPrev > (this.forwardF << 4) - 1 ) {
this.motionFwHPrev -= this.forwardF << 5;
}
else if( this.motionFwHPrev < ((-this.forwardF) << 4) ) {
this.motionFwHPrev += this.forwardF << 5;
}
this.motionFwH = this.motionFwHPrev;
if( this.fullPelForward ) {
this.motionFwH <<= 1;
}
// Vertical forward
code = this.readCode(MOTION);
if( (code != 0) && (this.forwardF != 1) ) {
r = this.buffer.getBits(this.forwardRSize);
d = ((Math.abs(code) - 1) << this.forwardRSize) + r + 1;
if( code < 0 ) {
d = -d;
}
}
else {
d = code;
}
this.motionFwVPrev += d;
if( this.motionFwVPrev > (this.forwardF << 4) - 1 ) {
this.motionFwVPrev -= this.forwardF << 5;
}
else if( this.motionFwVPrev < ((-this.forwardF) << 4) ) {
this.motionFwVPrev += this.forwardF << 5;
}
this.motionFwV = this.motionFwVPrev;
if( this.fullPelForward ) {
this.motionFwV <<= 1;
}
}
else if( this.pictureCodingType == PICTURE_TYPE_P ) {
// No motion information in P-picture, reset vectors
this.motionFwH = this.motionFwHPrev = 0;
this.motionFwV = this.motionFwVPrev = 0;
}
};
jsmpeg.prototype.copyMacroblock = function(motionH, motionV, sY, sCr, sCb ) {
var
width, scan,
H, V, oddH, oddV,
src, dest, last;
// We use 32bit writes here
var dY = this.currentY32;
var dCb = this.currentCb32;
var dCr = this.currentCr32;
// Luminance
width = this.codedWidth;
scan = width - 16;
H = motionH >> 1;
V = motionV >> 1;
oddH = (motionH & 1) == 1;
oddV = (motionV & 1) == 1;
src = ((this.mbRow << 4) + V) * width + (this.mbCol << 4) + H;
dest = (this.mbRow * width + this.mbCol) << 2;
last = dest + (width << 2);
var y1, y2, y;
if( oddH ) {
if( oddV ) {
while( dest < last ) {
y1 = sY[src] + sY[src+width]; src++;
for( var x = 0; x < 4; x++ ) {
y2 = sY[src] + sY[src+width]; src++;
y = (((y1 + y2 + 2) >> 2) & 0xff);
y1 = sY[src] + sY[src+width]; src++;
y |= (((y1 + y2 + 2) << 6) & 0xff00);
y2 = sY[src] + sY[src+width]; src++;
y |= (((y1 + y2 + 2) << 14) & 0xff0000);
y1 = sY[src] + sY[src+width]; src++;
y |= (((y1 + y2 + 2) << 22) & 0xff000000);
dY[dest++] = y;
}
dest += scan >> 2; src += scan-1;
}
}
else {
while( dest < last ) {
y1 = sY[src++];
for( var x = 0; x < 4; x++ ) {
y2 = sY[src++];
y = (((y1 + y2 + 1) >> 1) & 0xff);
y1 = sY[src++];
y |= (((y1 + y2 + 1) << 7) & 0xff00);
y2 = sY[src++];
y |= (((y1 + y2 + 1) << 15) & 0xff0000);
y1 = sY[src++];
y |= (((y1 + y2 + 1) << 23) & 0xff000000);
dY[dest++] = y;
}
dest += scan >> 2; src += scan-1;
}
}
}
else {
if( oddV ) {
while( dest < last ) {
for( var x = 0; x < 4; x++ ) {
y = (((sY[src] + sY[src+width] + 1) >> 1) & 0xff); src++;
y |= (((sY[src] + sY[src+width] + 1) << 7) & 0xff00); src++;
y |= (((sY[src] + sY[src+width] + 1) << 15) & 0xff0000); src++;
y |= (((sY[src] + sY[src+width] + 1) << 23) & 0xff000000); src++;
dY[dest++] = y;
}
dest += scan >> 2; src += scan;
}
}
else {
while( dest < last ) {
for( var x = 0; x < 4; x++ ) {
y = sY[src]; src++;
y |= sY[src] << 8; src++;
y |= sY[src] << 16; src++;
y |= sY[src] << 24; src++;
dY[dest++] = y;
}
dest += scan >> 2; src += scan;
}
}
}
if( this.bwFilter ) {
// No need to copy chrominance when black&white filter is active
return;
}
// Chrominance
width = this.halfWidth;
scan = width - 8;
H = (motionH/2) >> 1;
V = (motionV/2) >> 1;
oddH = ((motionH/2) & 1) == 1;
oddV = ((motionV/2) & 1) == 1;
src = ((this.mbRow << 3) + V) * width + (this.mbCol << 3) + H;
dest = (this.mbRow * width + this.mbCol) << 1;
last = dest + (width << 1);
var cr1, cr2, cr;
var cb1, cb2, cb;
if( oddH ) {
if( oddV ) {
while( dest < last ) {
cr1 = sCr[src] + sCr[src+width];
cb1 = sCb[src] + sCb[src+width];
src++;
for( var x = 0; x < 2; x++ ) {
cr2 = sCr[src] + sCr[src+width];
cb2 = sCb[src] + sCb[src+width]; src++;
cr = (((cr1 + cr2 + 2) >> 2) & 0xff);
cb = (((cb1 + cb2 + 2) >> 2) & 0xff);
cr1 = sCr[src] + sCr[src+width];
cb1 = sCb[src] + sCb[src+width]; src++;
cr |= (((cr1 + cr2 + 2) << 6) & 0xff00);
cb |= (((cb1 + cb2 + 2) << 6) & 0xff00);
cr2 = sCr[src] + sCr[src+width];
cb2 = sCb[src] + sCb[src+width]; src++;
cr |= (((cr1 + cr2 + 2) << 14) & 0xff0000);
cb |= (((cb1 + cb2 + 2) << 14) & 0xff0000);
cr1 = sCr[src] + sCr[src+width];
cb1 = sCb[src] + sCb[src+width]; src++;
cr |= (((cr1 + cr2 + 2) << 22) & 0xff000000);
cb |= (((cb1 + cb2 + 2) << 22) & 0xff000000);
dCr[dest] = cr;
dCb[dest] = cb;
dest++;
}
dest += scan >> 2; src += scan-1;
}
}
else {
while( dest < last ) {
cr1 = sCr[src];
cb1 = sCb[src];
src++;
for( var x = 0; x < 2; x++ ) {
cr2 = sCr[src];
cb2 = sCb[src++];
cr = (((cr1 + cr2 + 1) >> 1) & 0xff);
cb = (((cb1 + cb2 + 1) >> 1) & 0xff);
cr1 = sCr[src];
cb1 = sCb[src++];
cr |= (((cr1 + cr2 + 1) << 7) & 0xff00);
cb |= (((cb1 + cb2 + 1) << 7) & 0xff00);
cr2 = sCr[src];
cb2 = sCb[src++];
cr |= (((cr1 + cr2 + 1) << 15) & 0xff0000);
cb |= (((cb1 + cb2 + 1) << 15) & 0xff0000);
cr1 = sCr[src];
cb1 = sCb[src++];
cr |= (((cr1 + cr2 + 1) << 23) & 0xff000000);
cb |= (((cb1 + cb2 + 1) << 23) & 0xff000000);
dCr[dest] = cr;
dCb[dest] = cb;
dest++;
}
dest += scan >> 2; src += scan-1;
}
}
}
else {
if( oddV ) {
while( dest < last ) {
for( var x = 0; x < 2; x++ ) {
cr = (((sCr[src] + sCr[src+width] + 1) >> 1) & 0xff);
cb = (((sCb[src] + sCb[src+width] + 1) >> 1) & 0xff); src++;
cr |= (((sCr[src] + sCr[src+width] + 1) << 7) & 0xff00);
cb |= (((sCb[src] + sCb[src+width] + 1) << 7) & 0xff00); src++;
cr |= (((sCr[src] + sCr[src+width] + 1) << 15) & 0xff0000);
cb |= (((sCb[src] + sCb[src+width] + 1) << 15) & 0xff0000); src++;
cr |= (((sCr[src] + sCr[src+width] + 1) << 23) & 0xff000000);
cb |= (((sCb[src] + sCb[src+width] + 1) << 23) & 0xff000000); src++;
dCr[dest] = cr;
dCb[dest] = cb;
dest++;
}
dest += scan >> 2; src += scan;
}
}
else {
while( dest < last ) {
for( var x = 0; x < 2; x++ ) {
cr = sCr[src];
cb = sCb[src]; src++;
cr |= sCr[src] << 8;
cb |= sCb[src] << 8; src++;
cr |= sCr[src] << 16;
cb |= sCb[src] << 16; src++;
cr |= sCr[src] << 24;
cb |= sCb[src] << 24; src++;
dCr[dest] = cr;
dCb[dest] = cb;
dest++;
}
dest += scan >> 2; src += scan;
}
}
}
};
// ----------------------------------------------------------------------------
// Block layer
jsmpeg.prototype.dcPredictorY;
jsmpeg.prototype.dcPredictorCr;
jsmpeg.prototype.dcPredictorCb;
jsmpeg.prototype.blockData = null;
jsmpeg.prototype.decodeBlock = function(block) {
var
n = 0,
quantMatrix;
// Decode DC coefficient of intra-coded blocks
if( this.macroblockIntra ) {
var
predictor,
dctSize;
// DC prediction
if( block < 4 ) {
predictor = this.dcPredictorY;
dctSize = this.readCode(DCT_DC_SIZE_LUMINANCE);
}
else {
predictor = (block == 4 ? this.dcPredictorCr : this.dcPredictorCb);
dctSize = this.readCode(DCT_DC_SIZE_CHROMINANCE);
}
// Read DC coeff
if( dctSize > 0 ) {
var differential = this.buffer.getBits(dctSize);
if( (differential & (1 << (dctSize - 1))) != 0 ) {
this.blockData[0] = predictor + differential;
}
else {
this.blockData[0] = predictor + ((-1 << dctSize)|(differential+1));
}
}
else {
this.blockData[0] = predictor;
}
// Save predictor value
if( block < 4 ) {
this.dcPredictorY = this.blockData[0];
}
else if( block == 4 ) {
this.dcPredictorCr = this.blockData[0];
}
else {
this.dcPredictorCb = this.blockData[0];
}
// Dequantize + premultiply
this.blockData[0] <<= (3 + 5);
quantMatrix = this.intraQuantMatrix;
n = 1;
}
else {
quantMatrix = this.nonIntraQuantMatrix;
}
// Decode AC coefficients (+DC for non-intra)
var level = 0;
while( true ) {
var
run = 0,
coeff = this.readCode(DCT_COEFF);
if( (coeff == 0x0001) && (n > 0) && (this.buffer.getBits(1) == 0) ) {
// end_of_block
break;
}
if( coeff == 0xffff ) {
// escape
run = this.buffer.getBits(6);
level = this.buffer.getBits(8);
if( level == 0 ) {
level = this.buffer.getBits(8);
}
else if( level == 128 ) {
level = this.buffer.getBits(8) - 256;
}
else if( level > 128 ) {
level = level - 256;
}
}
else {
run = coeff >> 8;
level = coeff & 0xff;
if( this.buffer.getBits(1) ) {
level = -level;
}
}
n += run;
var dezigZagged = ZIG_ZAG[n];
n++;
// Dequantize, oddify, clip
level <<= 1;
if( !this.macroblockIntra ) {
level += (level < 0 ? -1 : 1);
}
level = (level * this.quantizerScale * quantMatrix[dezigZagged]) >> 4;
if( (level & 1) == 0 ) {
level -= level > 0 ? 1 : -1;
}
if( level > 2047 ) {
level = 2047;
}
else if( level < -2048 ) {
level = -2048;
}
// Save premultiplied coefficient
this.blockData[dezigZagged] = level * PREMULTIPLIER_MATRIX[dezigZagged];
};
// Move block to its place
var
destArray,
destIndex,
scan;
if( block < 4 ) {
destArray = this.currentY;
scan = this.codedWidth - 8;
destIndex = (this.mbRow * this.codedWidth + this.mbCol) << 4;
if( (block & 1) != 0 ) {
destIndex += 8;
}
if( (block & 2) != 0 ) {
destIndex += this.codedWidth << 3;
}
}
else {
destArray = (block == 4) ? this.currentCb : this.currentCr;
scan = (this.codedWidth >> 1) - 8;
destIndex = ((this.mbRow * this.codedWidth) << 2) + (this.mbCol << 3);
}
if( this.macroblockIntra ) {
// Overwrite (no prediction)
if (n == 1) {
this.copyValueToDestination((this.blockData[0] + 128) >> 8, destArray, destIndex, scan);
this.blockData[0] = 0;
} else {
this.IDCT();
this.copyBlockToDestination(this.blockData, destArray, destIndex, scan);
this.blockData.set(this.zeroBlockData);
}
}
else {
// Add data to the predicted macroblock
if (n == 1) {
this.addValueToDestination((this.blockData[0] + 128) >> 8, destArray, destIndex, scan);
this.blockData[0] = 0;
} else {
this.IDCT();
this.addBlockToDestination(this.blockData, destArray, destIndex, scan);
this.blockData.set(this.zeroBlockData);
}
}
};
jsmpeg.prototype.copyBlockToDestination = function(_blockData, _destArray, _destIndex, scan) {
var blockData = _blockData;
var destArray = _destArray;
var destIndex = _destIndex;
for (var n = 0; n < 64; n += 8, destIndex += scan+8) {
destArray[destIndex+0] = blockData[n+0];
destArray[destIndex+1] = blockData[n+1];
destArray[destIndex+2] = blockData[n+2];
destArray[destIndex+3] = blockData[n+3];
destArray[destIndex+4] = blockData[n+4];
destArray[destIndex+5] = blockData[n+5];
destArray[destIndex+6] = blockData[n+6];
destArray[destIndex+7] = blockData[n+7];
}
};
jsmpeg.prototype.addBlockToDestination = function(_blockData, _destArray, _destIndex, scan) {
var blockData = _blockData;
var destArray = _destArray;
var destIndex = _destIndex;
for (var n = 0; n < 64; n += 8, destIndex += scan+8) {
destArray[destIndex+0] += blockData[n+0];
destArray[destIndex+1] += blockData[n+1];
destArray[destIndex+2] += blockData[n+2];
destArray[destIndex+3] += blockData[n+3];
destArray[destIndex+4] += blockData[n+4];
destArray[destIndex+5] += blockData[n+5];
destArray[destIndex+6] += blockData[n+6];
destArray[destIndex+7] += blockData[n+7];
}
};
jsmpeg.prototype.copyValueToDestination = function(value, _destArray, _destIndex, scan) {
var destArray = _destArray;
var destIndex = _destIndex;
for (var n = 0; n < 64; n += 8, destIndex += scan+8) {
destArray[destIndex+0] = value;
destArray[destIndex+1] = value;
destArray[destIndex+2] = value;
destArray[destIndex+3] = value;
destArray[destIndex+4] = value;
destArray[destIndex+5] = value;
destArray[destIndex+6] = value;
destArray[destIndex+7] = value;
}
};
jsmpeg.prototype.addValueToDestination = function(value, _destArray, _destIndex, scan) {
var destArray = _destArray;
var destIndex = _destIndex;
for (var n = 0; n < 64; n += 8, destIndex += scan+8) {
destArray[destIndex+0] += value;
destArray[destIndex+1] += value;
destArray[destIndex+2] += value;
destArray[destIndex+3] += value;
destArray[destIndex+4] += value;
destArray[destIndex+5] += value;
destArray[destIndex+6] += value;
destArray[destIndex+7] += value;
}
};
jsmpeg.prototype.IDCT = function() {
// See http://vsr.informatik.tu-chemnitz.de/~jan/MPEG/HTML/IDCT.html
// for more info.
var
b1, b3, b4, b6, b7, tmp1, tmp2, m0,
x0, x1, x2, x3, x4, y3, y4, y5, y6, y7,
i,
blockData = this.blockData;
// Transform columns
for (i = 0; i < 8; ++i) {
b1 = blockData[4*8+i];
b3 = blockData[2*8+i] + blockData[6*8+i];
b4 = blockData[5*8+i] - blockData[3*8+i];
tmp1 = blockData[1*8+i] + blockData[7*8+i];
tmp2 = blockData[3*8+i] + blockData[5*8+i];
b6 = blockData[1*8+i] - blockData[7*8+i];
b7 = tmp1 + tmp2;
m0 = blockData[0*8+i];
x4 = ((b6*473 - b4*196 + 128) >> 8) - b7;
x0 = x4 - (((tmp1 - tmp2)*362 + 128) >> 8);
x1 = m0 - b1;
x2 = (((blockData[2*8+i] - blockData[6*8+i])*362 + 128) >> 8) - b3;
x3 = m0 + b1;
y3 = x1 + x2;
y4 = x3 + b3;
y5 = x1 - x2;
y6 = x3 - b3;
y7 = -x0 - ((b4*473 + b6*196 + 128) >> 8);
blockData[0*8+i] = b7 + y4;
blockData[1*8+i] = x4 + y3;
blockData[2*8+i] = y5 - x0;
blockData[3*8+i] = y6 - y7;
blockData[4*8+i] = y6 + y7;
blockData[5*8+i] = x0 + y5;
blockData[6*8+i] = y3 - x4;
blockData[7*8+i] = y4 - b7;
}
// Transform rows
for (i = 0; i < 64; i += 8) {
b1 = blockData[4+i];
b3 = blockData[2+i] + blockData[6+i];
b4 = blockData[5+i] - blockData[3+i];
tmp1 = blockData[1+i] + blockData[7+i];
tmp2 = blockData[3+i] + blockData[5+i];
b6 = blockData[1+i] - blockData[7+i];
b7 = tmp1 + tmp2;
m0 = blockData[0+i];
x4 = ((b6*473 - b4*196 + 128) >> 8) - b7;
x0 = x4 - (((tmp1 - tmp2)*362 + 128) >> 8);
x1 = m0 - b1;
x2 = (((blockData[2+i] - blockData[6+i])*362 + 128) >> 8) - b3;
x3 = m0 + b1;
y3 = x1 + x2;
y4 = x3 + b3;
y5 = x1 - x2;
y6 = x3 - b3;
y7 = -x0 - ((b4*473 + b6*196 + 128) >> 8);
blockData[0+i] = (b7 + y4 + 128) >> 8;
blockData[1+i] = (x4 + y3 + 128) >> 8;
blockData[2+i] = (y5 - x0 + 128) >> 8;
blockData[3+i] = (y6 - y7 + 128) >> 8;
blockData[4+i] = (y6 + y7 + 128) >> 8;
blockData[5+i] = (x0 + y5 + 128) >> 8;
blockData[6+i] = (y3 - x4 + 128) >> 8;
blockData[7+i] = (y4 - b7 + 128) >> 8;
}
};
// ----------------------------------------------------------------------------
// VLC Tables and Constants
var
SOCKET_MAGIC_BYTES = 'jsmp',
DECODE_SKIP_OUTPUT = 1,
PICTURE_RATE = [
0.000, 23.976, 24.000, 25.000, 29.970, 30.000, 50.000, 59.940,
60.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000
],
ZIG_ZAG = new Uint8Array([
0, 1, 8, 16, 9, 2, 3, 10,
17, 24, 32, 25, 18, 11, 4, 5,
12, 19, 26, 33, 40, 48, 41, 34,
27, 20, 13, 6, 7, 14, 21, 28,
35, 42, 49, 56, 57, 50, 43, 36,
29, 22, 15, 23, 30, 37, 44, 51,
58, 59, 52, 45, 38, 31, 39, 46,
53, 60, 61, 54, 47, 55, 62, 63
]),
DEFAULT_INTRA_QUANT_MATRIX = new Uint8Array([
8, 16, 19, 22, 26, 27, 29, 34,
16, 16, 22, 24, 27, 29, 34, 37,
19, 22, 26, 27, 29, 34, 34, 38,
22, 22, 26, 27, 29, 34, 37, 40,
22, 26, 27, 29, 32, 35, 40, 48,
26, 27, 29, 32, 35, 40, 48, 58,
26, 27, 29, 34, 38, 46, 56, 69,
27, 29, 35, 38, 46, 56, 69, 83
]),
DEFAULT_NON_INTRA_QUANT_MATRIX = new Uint8Array([
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16,
16, 16, 16, 16, 16, 16, 16, 16
]),
PREMULTIPLIER_MATRIX = new Uint8Array([
32, 44, 42, 38, 32, 25, 17, 9,
44, 62, 58, 52, 44, 35, 24, 12,
42, 58, 55, 49, 42, 33, 23, 12,
38, 52, 49, 44, 38, 30, 20, 10,
32, 44, 42, 38, 32, 25, 17, 9,
25, 35, 33, 30, 25, 20, 14, 7,
17, 24, 23, 20, 17, 14, 9, 5,
9, 12, 12, 10, 9, 7, 5, 2
]),
// MPEG-1 VLC
// macroblock_stuffing decodes as 34.
// macroblock_escape decodes as 35.
MACROBLOCK_ADDRESS_INCREMENT = new Int16Array([
1*3, 2*3, 0, // 0
3*3, 4*3, 0, // 1 0
0, 0, 1, // 2 1.
5*3, 6*3, 0, // 3 00
7*3, 8*3, 0, // 4 01
9*3, 10*3, 0, // 5 000
11*3, 12*3, 0, // 6 001
0, 0, 3, // 7 010.
0, 0, 2, // 8 011.
13*3, 14*3, 0, // 9 0000
15*3, 16*3, 0, // 10 0001
0, 0, 5, // 11 0010.
0, 0, 4, // 12 0011.
17*3, 18*3, 0, // 13 0000 0
19*3, 20*3, 0, // 14 0000 1
0, 0, 7, // 15 0001 0.
0, 0, 6, // 16 0001 1.
21*3, 22*3, 0, // 17 0000 00
23*3, 24*3, 0, // 18 0000 01
25*3, 26*3, 0, // 19 0000 10
27*3, 28*3, 0, // 20 0000 11
-1, 29*3, 0, // 21 0000 000
-1, 30*3, 0, // 22 0000 001
31*3, 32*3, 0, // 23 0000 010
33*3, 34*3, 0, // 24 0000 011
35*3, 36*3, 0, // 25 0000 100
37*3, 38*3, 0, // 26 0000 101
0, 0, 9, // 27 0000 110.
0, 0, 8, // 28 0000 111.
39*3, 40*3, 0, // 29 0000 0001
41*3, 42*3, 0, // 30 0000 0011
43*3, 44*3, 0, // 31 0000 0100
45*3, 46*3, 0, // 32 0000 0101
0, 0, 15, // 33 0000 0110.
0, 0, 14, // 34 0000 0111.
0, 0, 13, // 35 0000 1000.
0, 0, 12, // 36 0000 1001.
0, 0, 11, // 37 0000 1010.
0, 0, 10, // 38 0000 1011.
47*3, -1, 0, // 39 0000 0001 0
-1, 48*3, 0, // 40 0000 0001 1
49*3, 50*3, 0, // 41 0000 0011 0
51*3, 52*3, 0, // 42 0000 0011 1
53*3, 54*3, 0, // 43 0000 0100 0
55*3, 56*3, 0, // 44 0000 0100 1
57*3, 58*3, 0, // 45 0000 0101 0
59*3, 60*3, 0, // 46 0000 0101 1
61*3, -1, 0, // 47 0000 0001 00
-1, 62*3, 0, // 48 0000 0001 11
63*3, 64*3, 0, // 49 0000 0011 00
65*3, 66*3, 0, // 50 0000 0011 01
67*3, 68*3, 0, // 51 0000 0011 10
69*3, 70*3, 0, // 52 0000 0011 11
71*3, 72*3, 0, // 53 0000 0100 00
73*3, 74*3, 0, // 54 0000 0100 01
0, 0, 21, // 55 0000 0100 10.
0, 0, 20, // 56 0000 0100 11.
0, 0, 19, // 57 0000 0101 00.
0, 0, 18, // 58 0000 0101 01.
0, 0, 17, // 59 0000 0101 10.
0, 0, 16, // 60 0000 0101 11.
0, 0, 35, // 61 0000 0001 000. -- macroblock_escape
0, 0, 34, // 62 0000 0001 111. -- macroblock_stuffing
0, 0, 33, // 63 0000 0011 000.
0, 0, 32, // 64 0000 0011 001.
0, 0, 31, // 65 0000 0011 010.
0, 0, 30, // 66 0000 0011 011.
0, 0, 29, // 67 0000 0011 100.
0, 0, 28, // 68 0000 0011 101.
0, 0, 27, // 69 0000 0011 110.
0, 0, 26, // 70 0000 0011 111.
0, 0, 25, // 71 0000 0100 000.
0, 0, 24, // 72 0000 0100 001.
0, 0, 23, // 73 0000 0100 010.
0, 0, 22 // 74 0000 0100 011.
]),
// macroblock_type bitmap:
// 0x10 macroblock_quant
// 0x08 macroblock_motion_forward
// 0x04 macroblock_motion_backward
// 0x02 macrobkock_pattern
// 0x01 macroblock_intra
//
MACROBLOCK_TYPE_I = new Int8Array([
1*3, 2*3, 0, // 0
-1, 3*3, 0, // 1 0
0, 0, 0x01, // 2 1.
0, 0, 0x11 // 3 01.
]),
MACROBLOCK_TYPE_P = new Int8Array([
1*3, 2*3, 0, // 0
3*3, 4*3, 0, // 1 0
0, 0, 0x0a, // 2 1.
5*3, 6*3, 0, // 3 00
0, 0, 0x02, // 4 01.
7*3, 8*3, 0, // 5 000
0, 0, 0x08, // 6 001.
9*3, 10*3, 0, // 7 0000
11*3, 12*3, 0, // 8 0001
-1, 13*3, 0, // 9 00000
0, 0, 0x12, // 10 00001.
0, 0, 0x1a, // 11 00010.
0, 0, 0x01, // 12 00011.
0, 0, 0x11 // 13 000001.
]),
MACROBLOCK_TYPE_B = new Int8Array([
1*3, 2*3, 0, // 0
3*3, 5*3, 0, // 1 0
4*3, 6*3, 0, // 2 1
8*3, 7*3, 0, // 3 00
0, 0, 0x0c, // 4 10.
9*3, 10*3, 0, // 5 01
0, 0, 0x0e, // 6 11.
13*3, 14*3, 0, // 7 001
12*3, 11*3, 0, // 8 000
0, 0, 0x04, // 9 010.
0, 0, 0x06, // 10 011.
18*3, 16*3, 0, // 11 0001
15*3, 17*3, 0, // 12 0000
0, 0, 0x08, // 13 0010.
0, 0, 0x0a, // 14 0011.
-1, 19*3, 0, // 15 00000
0, 0, 0x01, // 16 00011.
20*3, 21*3, 0, // 17 00001
0, 0, 0x1e, // 18 00010.
0, 0, 0x11, // 19 000001.
0, 0, 0x16, // 20 000010.
0, 0, 0x1a // 21 000011.
]),
CODE_BLOCK_PATTERN = new Int16Array([
2*3, 1*3, 0, // 0
3*3, 6*3, 0, // 1 1
4*3, 5*3, 0, // 2 0
8*3, 11*3, 0, // 3 10
12*3, 13*3, 0, // 4 00
9*3, 7*3, 0, // 5 01
10*3, 14*3, 0, // 6 11
20*3, 19*3, 0, // 7 011
18*3, 16*3, 0, // 8 100
23*3, 17*3, 0, // 9 010
27*3, 25*3, 0, // 10 110
21*3, 28*3, 0, // 11 101
15*3, 22*3, 0, // 12 000
24*3, 26*3, 0, // 13 001
0, 0, 60, // 14 111.
35*3, 40*3, 0, // 15 0000
44*3, 48*3, 0, // 16 1001
38*3, 36*3, 0, // 17 0101
42*3, 47*3, 0, // 18 1000
29*3, 31*3, 0, // 19 0111
39*3, 32*3, 0, // 20 0110
0, 0, 32, // 21 1010.
45*3, 46*3, 0, // 22 0001
33*3, 41*3, 0, // 23 0100
43*3, 34*3, 0, // 24 0010
0, 0, 4, // 25 1101.
30*3, 37*3, 0, // 26 0011
0, 0, 8, // 27 1100.
0, 0, 16, // 28 1011.
0, 0, 44, // 29 0111 0.
50*3, 56*3, 0, // 30 0011 0
0, 0, 28, // 31 0111 1.
0, 0, 52, // 32 0110 1.
0, 0, 62, // 33 0100 0.
61*3, 59*3, 0, // 34 0010 1
52*3, 60*3, 0, // 35 0000 0
0, 0, 1, // 36 0101 1.
55*3, 54*3, 0, // 37 0011 1
0, 0, 61, // 38 0101 0.
0, 0, 56, // 39 0110 0.
57*3, 58*3, 0, // 40 0000 1
0, 0, 2, // 41 0100 1.
0, 0, 40, // 42 1000 0.
51*3, 62*3, 0, // 43 0010 0
0, 0, 48, // 44 1001 0.
64*3, 63*3, 0, // 45 0001 0
49*3, 53*3, 0, // 46 0001 1
0, 0, 20, // 47 1000 1.
0, 0, 12, // 48 1001 1.
80*3, 83*3, 0, // 49 0001 10
0, 0, 63, // 50 0011 00.
77*3, 75*3, 0, // 51 0010 00
65*3, 73*3, 0, // 52 0000 00
84*3, 66*3, 0, // 53 0001 11
0, 0, 24, // 54 0011 11.
0, 0, 36, // 55 0011 10.
0, 0, 3, // 56 0011 01.
69*3, 87*3, 0, // 57 0000 10
81*3, 79*3, 0, // 58 0000 11
68*3, 71*3, 0, // 59 0010 11
70*3, 78*3, 0, // 60 0000 01
67*3, 76*3, 0, // 61 0010 10
72*3, 74*3, 0, // 62 0010 01
86*3, 85*3, 0, // 63 0001 01
88*3, 82*3, 0, // 64 0001 00
-1, 94*3, 0, // 65 0000 000
95*3, 97*3, 0, // 66 0001 111
0, 0, 33, // 67 0010 100.
0, 0, 9, // 68 0010 110.
106*3, 110*3, 0, // 69 0000 100
102*3, 116*3, 0, // 70 0000 010
0, 0, 5, // 71 0010 111.
0, 0, 10, // 72 0010 010.
93*3, 89*3, 0, // 73 0000 001
0, 0, 6, // 74 0010 011.
0, 0, 18, // 75 0010 001.
0, 0, 17, // 76 0010 101.
0, 0, 34, // 77 0010 000.
113*3, 119*3, 0, // 78 0000 011
103*3, 104*3, 0, // 79 0000 111
90*3, 92*3, 0, // 80 0001 100
109*3, 107*3, 0, // 81 0000 110
117*3, 118*3, 0, // 82 0001 001
101*3, 99*3, 0, // 83 0001 101
98*3, 96*3, 0, // 84 0001 110
100*3, 91*3, 0, // 85 0001 011
114*3, 115*3, 0, // 86 0001 010
105*3, 108*3, 0, // 87 0000 101
112*3, 111*3, 0, // 88 0001 000
121*3, 125*3, 0, // 89 0000 0011
0, 0, 41, // 90 0001 1000.
0, 0, 14, // 91 0001 0111.
0, 0, 21, // 92 0001 1001.
124*3, 122*3, 0, // 93 0000 0010
120*3, 123*3, 0, // 94 0000 0001
0, 0, 11, // 95 0001 1110.
0, 0, 19, // 96 0001 1101.
0, 0, 7, // 97 0001 1111.
0, 0, 35, // 98 0001 1100.
0, 0, 13, // 99 0001 1011.
0, 0, 50, // 100 0001 0110.
0, 0, 49, // 101 0001 1010.
0, 0, 58, // 102 0000 0100.
0, 0, 37, // 103 0000 1110.
0, 0, 25, // 104 0000 1111.
0, 0, 45, // 105 0000 1010.
0, 0, 57, // 106 0000 1000.
0, 0, 26, // 107 0000 1101.
0, 0, 29, // 108 0000 1011.
0, 0, 38, // 109 0000 1100.
0, 0, 53, // 110 0000 1001.
0, 0, 23, // 111 0001 0001.
0, 0, 43, // 112 0001 0000.
0, 0, 46, // 113 0000 0110.
0, 0, 42, // 114 0001 0100.
0, 0, 22, // 115 0001 0101.
0, 0, 54, // 116 0000 0101.
0, 0, 51, // 117 0001 0010.
0, 0, 15, // 118 0001 0011.
0, 0, 30, // 119 0000 0111.
0, 0, 39, // 120 0000 0001 0.
0, 0, 47, // 121 0000 0011 0.
0, 0, 55, // 122 0000 0010 1.
0, 0, 27, // 123 0000 0001 1.
0, 0, 59, // 124 0000 0010 0.
0, 0, 31 // 125 0000 0011 1.
]),
MOTION = new Int16Array([
1*3, 2*3, 0, // 0
4*3, 3*3, 0, // 1 0
0, 0, 0, // 2 1.
6*3, 5*3, 0, // 3 01
8*3, 7*3, 0, // 4 00
0, 0, -1, // 5 011.
0, 0, 1, // 6 010.
9*3, 10*3, 0, // 7 001
12*3, 11*3, 0, // 8 000
0, 0, 2, // 9 0010.
0, 0, -2, // 10 0011.
14*3, 15*3, 0, // 11 0001
16*3, 13*3, 0, // 12 0000
20*3, 18*3, 0, // 13 0000 1
0, 0, 3, // 14 0001 0.
0, 0, -3, // 15 0001 1.
17*3, 19*3, 0, // 16 0000 0
-1, 23*3, 0, // 17 0000 00
27*3, 25*3, 0, // 18 0000 11
26*3, 21*3, 0, // 19 0000 01
24*3, 22*3, 0, // 20 0000 10
32*3, 28*3, 0, // 21 0000 011
29*3, 31*3, 0, // 22 0000 101
-1, 33*3, 0, // 23 0000 001
36*3, 35*3, 0, // 24 0000 100
0, 0, -4, // 25 0000 111.
30*3, 34*3, 0, // 26 0000 010
0, 0, 4, // 27 0000 110.
0, 0, -7, // 28 0000 0111.
0, 0, 5, // 29 0000 1010.
37*3, 41*3, 0, // 30 0000 0100
0, 0, -5, // 31 0000 1011.
0, 0, 7, // 32 0000 0110.
38*3, 40*3, 0, // 33 0000 0011
42*3, 39*3, 0, // 34 0000 0101
0, 0, -6, // 35 0000 1001.
0, 0, 6, // 36 0000 1000.
51*3, 54*3, 0, // 37 0000 0100 0
50*3, 49*3, 0, // 38 0000 0011 0
45*3, 46*3, 0, // 39 0000 0101 1
52*3, 47*3, 0, // 40 0000 0011 1
43*3, 53*3, 0, // 41 0000 0100 1
44*3, 48*3, 0, // 42 0000 0101 0
0, 0, 10, // 43 0000 0100 10.
0, 0, 9, // 44 0000 0101 00.
0, 0, 8, // 45 0000 0101 10.
0, 0, -8, // 46 0000 0101 11.
57*3, 66*3, 0, // 47 0000 0011 11
0, 0, -9, // 48 0000 0101 01.
60*3, 64*3, 0, // 49 0000 0011 01
56*3, 61*3, 0, // 50 0000 0011 00
55*3, 62*3, 0, // 51 0000 0100 00
58*3, 63*3, 0, // 52 0000 0011 10
0, 0, -10, // 53 0000 0100 11.
59*3, 65*3, 0, // 54 0000 0100 01
0, 0, 12, // 55 0000 0100 000.
0, 0, 16, // 56 0000 0011 000.
0, 0, 13, // 57 0000 0011 110.
0, 0, 14, // 58 0000 0011 100.
0, 0, 11, // 59 0000 0100 010.
0, 0, 15, // 60 0000 0011 010.
0, 0, -16, // 61 0000 0011 001.
0, 0, -12, // 62 0000 0100 001.
0, 0, -14, // 63 0000 0011 101.
0, 0, -15, // 64 0000 0011 011.
0, 0, -11, // 65 0000 0100 011.
0, 0, -13 // 66 0000 0011 111.
]),
DCT_DC_SIZE_LUMINANCE = new Int8Array([
2*3, 1*3, 0, // 0
6*3, 5*3, 0, // 1 1
3*3, 4*3, 0, // 2 0
0, 0, 1, // 3 00.
0, 0, 2, // 4 01.
9*3, 8*3, 0, // 5 11
7*3, 10*3, 0, // 6 10
0, 0, 0, // 7 100.
12*3, 11*3, 0, // 8 111
0, 0, 4, // 9 110.
0, 0, 3, // 10 101.
13*3, 14*3, 0, // 11 1111
0, 0, 5, // 12 1110.
0, 0, 6, // 13 1111 0.
16*3, 15*3, 0, // 14 1111 1
17*3, -1, 0, // 15 1111 11
0, 0, 7, // 16 1111 10.
0, 0, 8 // 17 1111 110.
]),
DCT_DC_SIZE_CHROMINANCE = new Int8Array([
2*3, 1*3, 0, // 0
4*3, 3*3, 0, // 1 1
6*3, 5*3, 0, // 2 0
8*3, 7*3, 0, // 3 11
0, 0, 2, // 4 10.
0, 0, 1, // 5 01.
0, 0, 0, // 6 00.
10*3, 9*3, 0, // 7 111
0, 0, 3, // 8 110.
12*3, 11*3, 0, // 9 1111
0, 0, 4, // 10 1110.
14*3, 13*3, 0, // 11 1111 1
0, 0, 5, // 12 1111 0.
16*3, 15*3, 0, // 13 1111 11
0, 0, 6, // 14 1111 10.
17*3, -1, 0, // 15 1111 111
0, 0, 7, // 16 1111 110.
0, 0, 8 // 17 1111 1110.
]),
// dct_coeff bitmap:
// 0xff00 run
// 0x00ff level
// Decoded values are unsigned. Sign bit follows in the stream.
// Interpretation of the value 0x0001
// for dc_coeff_first: run=0, level=1
// for dc_coeff_next: If the next bit is 1: run=0, level=1
// If the next bit is 0: end_of_block
// escape decodes as 0xffff.
DCT_COEFF = new Int32Array([
1*3, 2*3, 0, // 0
4*3, 3*3, 0, // 1 0
0, 0, 0x0001, // 2 1.
7*3, 8*3, 0, // 3 01
6*3, 5*3, 0, // 4 00
13*3, 9*3, 0, // 5 001
11*3, 10*3, 0, // 6 000
14*3, 12*3, 0, // 7 010
0, 0, 0x0101, // 8 011.
20*3, 22*3, 0, // 9 0011
18*3, 21*3, 0, // 10 0001
16*3, 19*3, 0, // 11 0000
0, 0, 0x0201, // 12 0101.
17*3, 15*3, 0, // 13 0010
0, 0, 0x0002, // 14 0100.
0, 0, 0x0003, // 15 0010 1.
27*3, 25*3, 0, // 16 0000 0
29*3, 31*3, 0, // 17 0010 0
24*3, 26*3, 0, // 18 0001 0
32*3, 30*3, 0, // 19 0000 1
0, 0, 0x0401, // 20 0011 0.
23*3, 28*3, 0, // 21 0001 1
0, 0, 0x0301, // 22 0011 1.
0, 0, 0x0102, // 23 0001 10.
0, 0, 0x0701, // 24 0001 00.
0, 0, 0xffff, // 25 0000 01. -- escape
0, 0, 0x0601, // 26 0001 01.
37*3, 36*3, 0, // 27 0000 00
0, 0, 0x0501, // 28 0001 11.
35*3, 34*3, 0, // 29 0010 00
39*3, 38*3, 0, // 30 0000 11
33*3, 42*3, 0, // 31 0010 01
40*3, 41*3, 0, // 32 0000 10
52*3, 50*3, 0, // 33 0010 010
54*3, 53*3, 0, // 34 0010 001
48*3, 49*3, 0, // 35 0010 000
43*3, 45*3, 0, // 36 0000 001
46*3, 44*3, 0, // 37 0000 000
0, 0, 0x0801, // 38 0000 111.
0, 0, 0x0004, // 39 0000 110.
0, 0, 0x0202, // 40 0000 100.
0, 0, 0x0901, // 41 0000 101.
51*3, 47*3, 0, // 42 0010 011
55*3, 57*3, 0, // 43 0000 0010
60*3, 56*3, 0, // 44 0000 0001
59*3, 58*3, 0, // 45 0000 0011
61*3, 62*3, 0, // 46 0000 0000
0, 0, 0x0a01, // 47 0010 0111.
0, 0, 0x0d01, // 48 0010 0000.
0, 0, 0x0006, // 49 0010 0001.
0, 0, 0x0103, // 50 0010 0101.
0, 0, 0x0005, // 51 0010 0110.
0, 0, 0x0302, // 52 0010 0100.
0, 0, 0x0b01, // 53 0010 0011.
0, 0, 0x0c01, // 54 0010 0010.
76*3, 75*3, 0, // 55 0000 0010 0
67*3, 70*3, 0, // 56 0000 0001 1
73*3, 71*3, 0, // 57 0000 0010 1
78*3, 74*3, 0, // 58 0000 0011 1
72*3, 77*3, 0, // 59 0000 0011 0
69*3, 64*3, 0, // 60 0000 0001 0
68*3, 63*3, 0, // 61 0000 0000 0
66*3, 65*3, 0, // 62 0000 0000 1
81*3, 87*3, 0, // 63 0000 0000 01
91*3, 80*3, 0, // 64 0000 0001 01
82*3, 79*3, 0, // 65 0000 0000 11
83*3, 86*3, 0, // 66 0000 0000 10
93*3, 92*3, 0, // 67 0000 0001 10
84*3, 85*3, 0, // 68 0000 0000 00
90*3, 94*3, 0, // 69 0000 0001 00
88*3, 89*3, 0, // 70 0000 0001 11
0, 0, 0x0203, // 71 0000 0010 11.
0, 0, 0x0104, // 72 0000 0011 00.
0, 0, 0x0007, // 73 0000 0010 10.
0, 0, 0x0402, // 74 0000 0011 11.
0, 0, 0x0502, // 75 0000 0010 01.
0, 0, 0x1001, // 76 0000 0010 00.
0, 0, 0x0f01, // 77 0000 0011 01.
0, 0, 0x0e01, // 78 0000 0011 10.
105*3, 107*3, 0, // 79 0000 0000 111
111*3, 114*3, 0, // 80 0000 0001 011
104*3, 97*3, 0, // 81 0000 0000 010
125*3, 119*3, 0, // 82 0000 0000 110
96*3, 98*3, 0, // 83 0000 0000 100
-1, 123*3, 0, // 84 0000 0000 000
95*3, 101*3, 0, // 85 0000 0000 001
106*3, 121*3, 0, // 86 0000 0000 101
99*3, 102*3, 0, // 87 0000 0000 011
113*3, 103*3, 0, // 88 0000 0001 110
112*3, 116*3, 0, // 89 0000 0001 111
110*3, 100*3, 0, // 90 0000 0001 000
124*3, 115*3, 0, // 91 0000 0001 010
117*3, 122*3, 0, // 92 0000 0001 101
109*3, 118*3, 0, // 93 0000 0001 100
120*3, 108*3, 0, // 94 0000 0001 001
127*3, 136*3, 0, // 95 0000 0000 0010
139*3, 140*3, 0, // 96 0000 0000 1000
130*3, 126*3, 0, // 97 0000 0000 0101
145*3, 146*3, 0, // 98 0000 0000 1001
128*3, 129*3, 0, // 99 0000 0000 0110
0, 0, 0x0802, // 100 0000 0001 0001.
132*3, 134*3, 0, // 101 0000 0000 0011
155*3, 154*3, 0, // 102 0000 0000 0111
0, 0, 0x0008, // 103 0000 0001 1101.
137*3, 133*3, 0, // 104 0000 0000 0100
143*3, 144*3, 0, // 105 0000 0000 1110
151*3, 138*3, 0, // 106 0000 0000 1010
142*3, 141*3, 0, // 107 0000 0000 1111
0, 0, 0x000a, // 108 0000 0001 0011.
0, 0, 0x0009, // 109 0000 0001 1000.
0, 0, 0x000b, // 110 0000 0001 0000.
0, 0, 0x1501, // 111 0000 0001 0110.
0, 0, 0x0602, // 112 0000 0001 1110.
0, 0, 0x0303, // 113 0000 0001 1100.
0, 0, 0x1401, // 114 0000 0001 0111.
0, 0, 0x0702, // 115 0000 0001 0101.
0, 0, 0x1101, // 116 0000 0001 1111.
0, 0, 0x1201, // 117 0000 0001 1010.
0, 0, 0x1301, // 118 0000 0001 1001.
148*3, 152*3, 0, // 119 0000 0000 1101
0, 0, 0x0403, // 120 0000 0001 0010.
153*3, 150*3, 0, // 121 0000 0000 1011
0, 0, 0x0105, // 122 0000 0001 1011.
131*3, 135*3, 0, // 123 0000 0000 0001
0, 0, 0x0204, // 124 0000 0001 0100.
149*3, 147*3, 0, // 125 0000 0000 1100
172*3, 173*3, 0, // 126 0000 0000 0101 1
162*3, 158*3, 0, // 127 0000 0000 0010 0
170*3, 161*3, 0, // 128 0000 0000 0110 0
168*3, 166*3, 0, // 129 0000 0000 0110 1
157*3, 179*3, 0, // 130 0000 0000 0101 0
169*3, 167*3, 0, // 131 0000 0000 0001 0
174*3, 171*3, 0, // 132 0000 0000 0011 0
178*3, 177*3, 0, // 133 0000 0000 0100 1
156*3, 159*3, 0, // 134 0000 0000 0011 1
164*3, 165*3, 0, // 135 0000 0000 0001 1
183*3, 182*3, 0, // 136 0000 0000 0010 1
175*3, 176*3, 0, // 137 0000 0000 0100 0
0, 0, 0x0107, // 138 0000 0000 1010 1.
0, 0, 0x0a02, // 139 0000 0000 1000 0.
0, 0, 0x0902, // 140 0000 0000 1000 1.
0, 0, 0x1601, // 141 0000 0000 1111 1.
0, 0, 0x1701, // 142 0000 0000 1111 0.
0, 0, 0x1901, // 143 0000 0000 1110 0.
0, 0, 0x1801, // 144 0000 0000 1110 1.
0, 0, 0x0503, // 145 0000 0000 1001 0.
0, 0, 0x0304, // 146 0000 0000 1001 1.
0, 0, 0x000d, // 147 0000 0000 1100 1.
0, 0, 0x000c, // 148 0000 0000 1101 0.
0, 0, 0x000e, // 149 0000 0000 1100 0.
0, 0, 0x000f, // 150 0000 0000 1011 1.
0, 0, 0x0205, // 151 0000 0000 1010 0.
0, 0, 0x1a01, // 152 0000 0000 1101 1.
0, 0, 0x0106, // 153 0000 0000 1011 0.
180*3, 181*3, 0, // 154 0000 0000 0111 1
160*3, 163*3, 0, // 155 0000 0000 0111 0
196*3, 199*3, 0, // 156 0000 0000 0011 10
0, 0, 0x001b, // 157 0000 0000 0101 00.
203*3, 185*3, 0, // 158 0000 0000 0010 01
202*3, 201*3, 0, // 159 0000 0000 0011 11
0, 0, 0x0013, // 160 0000 0000 0111 00.
0, 0, 0x0016, // 161 0000 0000 0110 01.
197*3, 207*3, 0, // 162 0000 0000 0010 00
0, 0, 0x0012, // 163 0000 0000 0111 01.
191*3, 192*3, 0, // 164 0000 0000 0001 10
188*3, 190*3, 0, // 165 0000 0000 0001 11
0, 0, 0x0014, // 166 0000 0000 0110 11.
184*3, 194*3, 0, // 167 0000 0000 0001 01
0, 0, 0x0015, // 168 0000 0000 0110 10.
186*3, 193*3, 0, // 169 0000 0000 0001 00
0, 0, 0x0017, // 170 0000 0000 0110 00.
204*3, 198*3, 0, // 171 0000 0000 0011 01
0, 0, 0x0019, // 172 0000 0000 0101 10.
0, 0, 0x0018, // 173 0000 0000 0101 11.
200*3, 205*3, 0, // 174 0000 0000 0011 00
0, 0, 0x001f, // 175 0000 0000 0100 00.
0, 0, 0x001e, // 176 0000 0000 0100 01.
0, 0, 0x001c, // 177 0000 0000 0100 11.
0, 0, 0x001d, // 178 0000 0000 0100 10.
0, 0, 0x001a, // 179 0000 0000 0101 01.
0, 0, 0x0011, // 180 0000 0000 0111 10.
0, 0, 0x0010, // 181 0000 0000 0111 11.
189*3, 206*3, 0, // 182 0000 0000 0010 11
187*3, 195*3, 0, // 183 0000 0000 0010 10
218*3, 211*3, 0, // 184 0000 0000 0001 010
0, 0, 0x0025, // 185 0000 0000 0010 011.
215*3, 216*3, 0, // 186 0000 0000 0001 000
0, 0, 0x0024, // 187 0000 0000 0010 100.
210*3, 212*3, 0, // 188 0000 0000 0001 110
0, 0, 0x0022, // 189 0000 0000 0010 110.
213*3, 209*3, 0, // 190 0000 0000 0001 111
221*3, 222*3, 0, // 191 0000 0000 0001 100
219*3, 208*3, 0, // 192 0000 0000 0001 101
217*3, 214*3, 0, // 193 0000 0000 0001 001
223*3, 220*3, 0, // 194 0000 0000 0001 011
0, 0, 0x0023, // 195 0000 0000 0010 101.
0, 0, 0x010b, // 196 0000 0000 0011 100.
0, 0, 0x0028, // 197 0000 0000 0010 000.
0, 0, 0x010c, // 198 0000 0000 0011 011.
0, 0, 0x010a, // 199 0000 0000 0011 101.
0, 0, 0x0020, // 200 0000 0000 0011 000.
0, 0, 0x0108, // 201 0000 0000 0011 111.
0, 0, 0x0109, // 202 0000 0000 0011 110.
0, 0, 0x0026, // 203 0000 0000 0010 010.
0, 0, 0x010d, // 204 0000 0000 0011 010.
0, 0, 0x010e, // 205 0000 0000 0011 001.
0, 0, 0x0021, // 206 0000 0000 0010 111.
0, 0, 0x0027, // 207 0000 0000 0010 001.
0, 0, 0x1f01, // 208 0000 0000 0001 1011.
0, 0, 0x1b01, // 209 0000 0000 0001 1111.
0, 0, 0x1e01, // 210 0000 0000 0001 1100.
0, 0, 0x1002, // 211 0000 0000 0001 0101.
0, 0, 0x1d01, // 212 0000 0000 0001 1101.
0, 0, 0x1c01, // 213 0000 0000 0001 1110.
0, 0, 0x010f, // 214 0000 0000 0001 0011.
0, 0, 0x0112, // 215 0000 0000 0001 0000.
0, 0, 0x0111, // 216 0000 0000 0001 0001.
0, 0, 0x0110, // 217 0000 0000 0001 0010.
0, 0, 0x0603, // 218 0000 0000 0001 0100.
0, 0, 0x0b02, // 219 0000 0000 0001 1010.
0, 0, 0x0e02, // 220 0000 0000 0001 0111.
0, 0, 0x0d02, // 221 0000 0000 0001 1000.
0, 0, 0x0c02, // 222 0000 0000 0001 1001.
0, 0, 0x0f02 // 223 0000 0000 0001 0110.
]),
PICTURE_TYPE_I = 1,
PICTURE_TYPE_P = 2,
PICTURE_TYPE_B = 3,
PICTURE_TYPE_D = 4,
START_SEQUENCE = 0xB3,
START_SLICE_FIRST = 0x01,
START_SLICE_LAST = 0xAF,
START_PICTURE = 0x00,
START_EXTENSION = 0xB5,
START_USER_DATA = 0xB2;
var MACROBLOCK_TYPE_TABLES = [
null,
MACROBLOCK_TYPE_I,
MACROBLOCK_TYPE_P,
MACROBLOCK_TYPE_B
];
// ----------------------------------------------------------------------------
// Bit Reader
var BitReader = function(arrayBuffer) {
this.bytes = new Uint8Array(arrayBuffer);
this.length = this.bytes.length;
this.writePos = this.bytes.length;
this.index = 0;
};
BitReader.NOT_FOUND = -1;
BitReader.prototype.findNextMPEGStartCode = function() {
for( var i = (this.index+7 >> 3); i < this.writePos; i++ ) {
if(
this.bytes[i] == 0x00 &&
this.bytes[i+1] == 0x00 &&
this.bytes[i+2] == 0x01
) {
this.index = (i+4) << 3;
return this.bytes[i+3];
}
}
this.index = (this.writePos << 3);
return BitReader.NOT_FOUND;
};
BitReader.prototype.nextBytesAreStartCode = function() {
var i = (this.index+7 >> 3);
return (
i >= this.writePos || (
this.bytes[i] == 0x00 &&
this.bytes[i+1] == 0x00 &&
this.bytes[i+2] == 0x01
)
);
};
BitReader.prototype.nextBits = function(count) {
var
byteOffset = this.index >> 3,
room = (8 - this.index % 8);
if( room >= count ) {
return (this.bytes[byteOffset] >> (room - count)) & (0xff >> (8-count));
}
var
leftover = (this.index + count) % 8, // Leftover bits in last byte
end = (this.index + count -1) >> 3,
value = this.bytes[byteOffset] & (0xff >> (8-room)); // Fill out first byte
for( byteOffset++; byteOffset < end; byteOffset++ ) {
value <<= 8; // Shift and
value |= this.bytes[byteOffset]; // Put next byte
}
if (leftover > 0) {
value <<= leftover; // Make room for remaining bits
value |= (this.bytes[byteOffset] >> (8 - leftover));
}
else {
value <<= 8;
value |= this.bytes[byteOffset];
}
return value;
};
BitReader.prototype.getBits = function(count) {
var value = this.nextBits(count);
this.index += count;
return value;
};
BitReader.prototype.advance = function(count) {
return (this.index += count);
};
BitReader.prototype.rewind = function(count) {
return (this.index -= count);
};
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