3601 lines
108 KiB
JavaScript
3601 lines
108 KiB
JavaScript
(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.muxjs = f()}})(function(){var define,module,exports;return (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);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.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){
|
||
'use strict';
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||
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||
var Stream = require('../utils/stream.js');
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||
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||
var AdtsStream;
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||
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var
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||
ADTS_SAMPLING_FREQUENCIES = [
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||
96000,
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||
88200,
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||
64000,
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||
48000,
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||
44100,
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||
32000,
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||
24000,
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||
22050,
|
||
16000,
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||
12000,
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||
11025,
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8000,
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7350
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||
];
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||
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/*
|
||
* Accepts a ElementaryStream and emits data events with parsed
|
||
* AAC Audio Frames of the individual packets. Input audio in ADTS
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* format is unpacked and re-emitted as AAC frames.
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||
*
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||
* @see http://wiki.multimedia.cx/index.php?title=ADTS
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||
* @see http://wiki.multimedia.cx/?title=Understanding_AAC
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*/
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AdtsStream = function() {
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var buffer;
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AdtsStream.prototype.init.call(this);
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this.push = function(packet) {
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var
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i = 0,
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frameNum = 0,
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frameLength,
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||
protectionSkipBytes,
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||
frameEnd,
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||
oldBuffer,
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||
sampleCount,
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||
adtsFrameDuration;
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if (packet.type !== 'audio') {
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||
// ignore non-audio data
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||
return;
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||
}
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// Prepend any data in the buffer to the input data so that we can parse
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// aac frames the cross a PES packet boundary
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if (buffer) {
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oldBuffer = buffer;
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buffer = new Uint8Array(oldBuffer.byteLength + packet.data.byteLength);
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buffer.set(oldBuffer);
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buffer.set(packet.data, oldBuffer.byteLength);
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||
} else {
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buffer = packet.data;
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}
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// unpack any ADTS frames which have been fully received
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// for details on the ADTS header, see http://wiki.multimedia.cx/index.php?title=ADTS
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while (i + 5 < buffer.length) {
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||
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// Loook for the start of an ADTS header..
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if (buffer[i] !== 0xFF || (buffer[i + 1] & 0xF6) !== 0xF0) {
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// If a valid header was not found, jump one forward and attempt to
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// find a valid ADTS header starting at the next byte
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i++;
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continue;
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}
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// The protection skip bit tells us if we have 2 bytes of CRC data at the
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// end of the ADTS header
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protectionSkipBytes = (~buffer[i + 1] & 0x01) * 2;
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// Frame length is a 13 bit integer starting 16 bits from the
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// end of the sync sequence
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frameLength = ((buffer[i + 3] & 0x03) << 11) |
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(buffer[i + 4] << 3) |
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((buffer[i + 5] & 0xe0) >> 5);
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sampleCount = ((buffer[i + 6] & 0x03) + 1) * 1024;
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adtsFrameDuration = (sampleCount * 90000) /
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ADTS_SAMPLING_FREQUENCIES[(buffer[i + 2] & 0x3c) >>> 2];
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frameEnd = i + frameLength;
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// If we don't have enough data to actually finish this ADTS frame, return
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||
// and wait for more data
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if (buffer.byteLength < frameEnd) {
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return;
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||
}
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// Otherwise, deliver the complete AAC frame
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this.trigger('data', {
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pts: packet.pts + (frameNum * adtsFrameDuration),
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dts: packet.dts + (frameNum * adtsFrameDuration),
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sampleCount: sampleCount,
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audioobjecttype: ((buffer[i + 2] >>> 6) & 0x03) + 1,
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channelcount: ((buffer[i + 2] & 1) << 2) |
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((buffer[i + 3] & 0xc0) >>> 6),
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samplerate: ADTS_SAMPLING_FREQUENCIES[(buffer[i + 2] & 0x3c) >>> 2],
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samplingfrequencyindex: (buffer[i + 2] & 0x3c) >>> 2,
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// assume ISO/IEC 14496-12 AudioSampleEntry default of 16
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samplesize: 16,
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data: buffer.subarray(i + 7 + protectionSkipBytes, frameEnd)
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});
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// If the buffer is empty, clear it and return
|
||
if (buffer.byteLength === frameEnd) {
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buffer = undefined;
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return;
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}
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frameNum++;
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// Remove the finished frame from the buffer and start the process again
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buffer = buffer.subarray(frameEnd);
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}
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};
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this.flush = function() {
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this.trigger('done');
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};
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};
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AdtsStream.prototype = new Stream();
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module.exports = AdtsStream;
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},{"../utils/stream.js":15}],2:[function(require,module,exports){
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'use strict';
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var Stream = require('../utils/stream.js');
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var ExpGolomb = require('../utils/exp-golomb.js');
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var H264Stream, NalByteStream;
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var PROFILES_WITH_OPTIONAL_SPS_DATA;
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/**
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* Accepts a NAL unit byte stream and unpacks the embedded NAL units.
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*/
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NalByteStream = function() {
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var
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syncPoint = 0,
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i,
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buffer;
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NalByteStream.prototype.init.call(this);
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this.push = function(data) {
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var swapBuffer;
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if (!buffer) {
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buffer = data.data;
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} else {
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swapBuffer = new Uint8Array(buffer.byteLength + data.data.byteLength);
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swapBuffer.set(buffer);
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swapBuffer.set(data.data, buffer.byteLength);
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buffer = swapBuffer;
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}
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// Rec. ITU-T H.264, Annex B
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||
// scan for NAL unit boundaries
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// a match looks like this:
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// 0 0 1 .. NAL .. 0 0 1
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// ^ sync point ^ i
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// or this:
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// 0 0 1 .. NAL .. 0 0 0
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// ^ sync point ^ i
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// advance the sync point to a NAL start, if necessary
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for (; syncPoint < buffer.byteLength - 3; syncPoint++) {
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if (buffer[syncPoint + 2] === 1) {
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// the sync point is properly aligned
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i = syncPoint + 5;
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break;
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}
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}
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while (i < buffer.byteLength) {
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// look at the current byte to determine if we've hit the end of
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// a NAL unit boundary
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||
switch (buffer[i]) {
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||
case 0:
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||
// skip past non-sync sequences
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||
if (buffer[i - 1] !== 0) {
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i += 2;
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break;
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} else if (buffer[i - 2] !== 0) {
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i++;
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break;
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||
}
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// deliver the NAL unit if it isn't empty
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if (syncPoint + 3 !== i - 2) {
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this.trigger('data', buffer.subarray(syncPoint + 3, i - 2));
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}
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// drop trailing zeroes
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||
do {
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i++;
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} while (buffer[i] !== 1 && i < buffer.length);
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syncPoint = i - 2;
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i += 3;
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break;
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case 1:
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||
// skip past non-sync sequences
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if (buffer[i - 1] !== 0 ||
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||
buffer[i - 2] !== 0) {
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i += 3;
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break;
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||
}
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||
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// deliver the NAL unit
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this.trigger('data', buffer.subarray(syncPoint + 3, i - 2));
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||
syncPoint = i - 2;
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||
i += 3;
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||
break;
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default:
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||
// the current byte isn't a one or zero, so it cannot be part
|
||
// of a sync sequence
|
||
i += 3;
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||
break;
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||
}
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||
}
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// filter out the NAL units that were delivered
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buffer = buffer.subarray(syncPoint);
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i -= syncPoint;
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syncPoint = 0;
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||
};
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||
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this.flush = function() {
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||
// deliver the last buffered NAL unit
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||
if (buffer && buffer.byteLength > 3) {
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||
this.trigger('data', buffer.subarray(syncPoint + 3));
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||
}
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||
// reset the stream state
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||
buffer = null;
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||
syncPoint = 0;
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||
this.trigger('done');
|
||
};
|
||
};
|
||
NalByteStream.prototype = new Stream();
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||
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||
// values of profile_idc that indicate additional fields are included in the SPS
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||
// see Recommendation ITU-T H.264 (4/2013),
|
||
// 7.3.2.1.1 Sequence parameter set data syntax
|
||
PROFILES_WITH_OPTIONAL_SPS_DATA = {
|
||
100: true,
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||
110: true,
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||
122: true,
|
||
244: true,
|
||
44: true,
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||
83: true,
|
||
86: true,
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||
118: true,
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||
128: true,
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||
138: true,
|
||
139: true,
|
||
134: true
|
||
};
|
||
|
||
/**
|
||
* Accepts input from a ElementaryStream and produces H.264 NAL unit data
|
||
* events.
|
||
*/
|
||
H264Stream = function() {
|
||
var
|
||
nalByteStream = new NalByteStream(),
|
||
self,
|
||
trackId,
|
||
currentPts,
|
||
currentDts,
|
||
|
||
discardEmulationPreventionBytes,
|
||
readSequenceParameterSet,
|
||
skipScalingList;
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||
|
||
H264Stream.prototype.init.call(this);
|
||
self = this;
|
||
|
||
this.push = function(packet) {
|
||
if (packet.type !== 'video') {
|
||
return;
|
||
}
|
||
trackId = packet.trackId;
|
||
currentPts = packet.pts;
|
||
currentDts = packet.dts;
|
||
|
||
nalByteStream.push(packet);
|
||
};
|
||
|
||
nalByteStream.on('data', function(data) {
|
||
var
|
||
event = {
|
||
trackId: trackId,
|
||
pts: currentPts,
|
||
dts: currentDts,
|
||
data: data
|
||
};
|
||
|
||
switch (data[0] & 0x1f) {
|
||
case 0x05:
|
||
event.nalUnitType = 'slice_layer_without_partitioning_rbsp_idr';
|
||
break;
|
||
case 0x06:
|
||
event.nalUnitType = 'sei_rbsp';
|
||
event.escapedRBSP = discardEmulationPreventionBytes(data.subarray(1));
|
||
break;
|
||
case 0x07:
|
||
event.nalUnitType = 'seq_parameter_set_rbsp';
|
||
event.escapedRBSP = discardEmulationPreventionBytes(data.subarray(1));
|
||
event.config = readSequenceParameterSet(event.escapedRBSP);
|
||
break;
|
||
case 0x08:
|
||
event.nalUnitType = 'pic_parameter_set_rbsp';
|
||
break;
|
||
case 0x09:
|
||
event.nalUnitType = 'access_unit_delimiter_rbsp';
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
self.trigger('data', event);
|
||
});
|
||
nalByteStream.on('done', function() {
|
||
self.trigger('done');
|
||
});
|
||
|
||
this.flush = function() {
|
||
nalByteStream.flush();
|
||
};
|
||
|
||
/**
|
||
* Advance the ExpGolomb decoder past a scaling list. The scaling
|
||
* list is optionally transmitted as part of a sequence parameter
|
||
* set and is not relevant to transmuxing.
|
||
* @param count {number} the number of entries in this scaling list
|
||
* @param expGolombDecoder {object} an ExpGolomb pointed to the
|
||
* start of a scaling list
|
||
* @see Recommendation ITU-T H.264, Section 7.3.2.1.1.1
|
||
*/
|
||
skipScalingList = function(count, expGolombDecoder) {
|
||
var
|
||
lastScale = 8,
|
||
nextScale = 8,
|
||
j,
|
||
deltaScale;
|
||
|
||
for (j = 0; j < count; j++) {
|
||
if (nextScale !== 0) {
|
||
deltaScale = expGolombDecoder.readExpGolomb();
|
||
nextScale = (lastScale + deltaScale + 256) % 256;
|
||
}
|
||
|
||
lastScale = (nextScale === 0) ? lastScale : nextScale;
|
||
}
|
||
};
|
||
|
||
/**
|
||
* Expunge any "Emulation Prevention" bytes from a "Raw Byte
|
||
* Sequence Payload"
|
||
* @param data {Uint8Array} the bytes of a RBSP from a NAL
|
||
* unit
|
||
* @return {Uint8Array} the RBSP without any Emulation
|
||
* Prevention Bytes
|
||
*/
|
||
discardEmulationPreventionBytes = function(data) {
|
||
var
|
||
length = data.byteLength,
|
||
emulationPreventionBytesPositions = [],
|
||
i = 1,
|
||
newLength, newData;
|
||
|
||
// Find all `Emulation Prevention Bytes`
|
||
while (i < length - 2) {
|
||
if (data[i] === 0 && data[i + 1] === 0 && data[i + 2] === 0x03) {
|
||
emulationPreventionBytesPositions.push(i + 2);
|
||
i += 2;
|
||
} else {
|
||
i++;
|
||
}
|
||
}
|
||
|
||
// If no Emulation Prevention Bytes were found just return the original
|
||
// array
|
||
if (emulationPreventionBytesPositions.length === 0) {
|
||
return data;
|
||
}
|
||
|
||
// Create a new array to hold the NAL unit data
|
||
newLength = length - emulationPreventionBytesPositions.length;
|
||
newData = new Uint8Array(newLength);
|
||
var sourceIndex = 0;
|
||
|
||
for (i = 0; i < newLength; sourceIndex++, i++) {
|
||
if (sourceIndex === emulationPreventionBytesPositions[0]) {
|
||
// Skip this byte
|
||
sourceIndex++;
|
||
// Remove this position index
|
||
emulationPreventionBytesPositions.shift();
|
||
}
|
||
newData[i] = data[sourceIndex];
|
||
}
|
||
|
||
return newData;
|
||
};
|
||
|
||
/**
|
||
* Read a sequence parameter set and return some interesting video
|
||
* properties. A sequence parameter set is the H264 metadata that
|
||
* describes the properties of upcoming video frames.
|
||
* @param data {Uint8Array} the bytes of a sequence parameter set
|
||
* @return {object} an object with configuration parsed from the
|
||
* sequence parameter set, including the dimensions of the
|
||
* associated video frames.
|
||
*/
|
||
readSequenceParameterSet = function(data) {
|
||
var
|
||
frameCropLeftOffset = 0,
|
||
frameCropRightOffset = 0,
|
||
frameCropTopOffset = 0,
|
||
frameCropBottomOffset = 0,
|
||
sarScale = 1,
|
||
expGolombDecoder, profileIdc, levelIdc, profileCompatibility,
|
||
chromaFormatIdc, picOrderCntType,
|
||
numRefFramesInPicOrderCntCycle, picWidthInMbsMinus1,
|
||
picHeightInMapUnitsMinus1,
|
||
frameMbsOnlyFlag,
|
||
scalingListCount,
|
||
sarRatio,
|
||
aspectRatioIdc,
|
||
i;
|
||
|
||
expGolombDecoder = new ExpGolomb(data);
|
||
profileIdc = expGolombDecoder.readUnsignedByte(); // profile_idc
|
||
profileCompatibility = expGolombDecoder.readUnsignedByte(); // constraint_set[0-5]_flag
|
||
levelIdc = expGolombDecoder.readUnsignedByte(); // level_idc u(8)
|
||
expGolombDecoder.skipUnsignedExpGolomb(); // seq_parameter_set_id
|
||
|
||
// some profiles have more optional data we don't need
|
||
if (PROFILES_WITH_OPTIONAL_SPS_DATA[profileIdc]) {
|
||
chromaFormatIdc = expGolombDecoder.readUnsignedExpGolomb();
|
||
if (chromaFormatIdc === 3) {
|
||
expGolombDecoder.skipBits(1); // separate_colour_plane_flag
|
||
}
|
||
expGolombDecoder.skipUnsignedExpGolomb(); // bit_depth_luma_minus8
|
||
expGolombDecoder.skipUnsignedExpGolomb(); // bit_depth_chroma_minus8
|
||
expGolombDecoder.skipBits(1); // qpprime_y_zero_transform_bypass_flag
|
||
if (expGolombDecoder.readBoolean()) { // seq_scaling_matrix_present_flag
|
||
scalingListCount = (chromaFormatIdc !== 3) ? 8 : 12;
|
||
for (i = 0; i < scalingListCount; i++) {
|
||
if (expGolombDecoder.readBoolean()) { // seq_scaling_list_present_flag[ i ]
|
||
if (i < 6) {
|
||
skipScalingList(16, expGolombDecoder);
|
||
} else {
|
||
skipScalingList(64, expGolombDecoder);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
expGolombDecoder.skipUnsignedExpGolomb(); // log2_max_frame_num_minus4
|
||
picOrderCntType = expGolombDecoder.readUnsignedExpGolomb();
|
||
|
||
if (picOrderCntType === 0) {
|
||
expGolombDecoder.readUnsignedExpGolomb(); // log2_max_pic_order_cnt_lsb_minus4
|
||
} else if (picOrderCntType === 1) {
|
||
expGolombDecoder.skipBits(1); // delta_pic_order_always_zero_flag
|
||
expGolombDecoder.skipExpGolomb(); // offset_for_non_ref_pic
|
||
expGolombDecoder.skipExpGolomb(); // offset_for_top_to_bottom_field
|
||
numRefFramesInPicOrderCntCycle = expGolombDecoder.readUnsignedExpGolomb();
|
||
for (i = 0; i < numRefFramesInPicOrderCntCycle; i++) {
|
||
expGolombDecoder.skipExpGolomb(); // offset_for_ref_frame[ i ]
|
||
}
|
||
}
|
||
|
||
expGolombDecoder.skipUnsignedExpGolomb(); // max_num_ref_frames
|
||
expGolombDecoder.skipBits(1); // gaps_in_frame_num_value_allowed_flag
|
||
|
||
picWidthInMbsMinus1 = expGolombDecoder.readUnsignedExpGolomb();
|
||
picHeightInMapUnitsMinus1 = expGolombDecoder.readUnsignedExpGolomb();
|
||
|
||
frameMbsOnlyFlag = expGolombDecoder.readBits(1);
|
||
if (frameMbsOnlyFlag === 0) {
|
||
expGolombDecoder.skipBits(1); // mb_adaptive_frame_field_flag
|
||
}
|
||
|
||
expGolombDecoder.skipBits(1); // direct_8x8_inference_flag
|
||
if (expGolombDecoder.readBoolean()) { // frame_cropping_flag
|
||
frameCropLeftOffset = expGolombDecoder.readUnsignedExpGolomb();
|
||
frameCropRightOffset = expGolombDecoder.readUnsignedExpGolomb();
|
||
frameCropTopOffset = expGolombDecoder.readUnsignedExpGolomb();
|
||
frameCropBottomOffset = expGolombDecoder.readUnsignedExpGolomb();
|
||
}
|
||
if (expGolombDecoder.readBoolean()) {
|
||
// vui_parameters_present_flag
|
||
if (expGolombDecoder.readBoolean()) {
|
||
// aspect_ratio_info_present_flag
|
||
aspectRatioIdc = expGolombDecoder.readUnsignedByte();
|
||
switch (aspectRatioIdc) {
|
||
case 1: sarRatio = [1, 1]; break;
|
||
case 2: sarRatio = [12, 11]; break;
|
||
case 3: sarRatio = [10, 11]; break;
|
||
case 4: sarRatio = [16, 11]; break;
|
||
case 5: sarRatio = [40, 33]; break;
|
||
case 6: sarRatio = [24, 11]; break;
|
||
case 7: sarRatio = [20, 11]; break;
|
||
case 8: sarRatio = [32, 11]; break;
|
||
case 9: sarRatio = [80, 33]; break;
|
||
case 10: sarRatio = [18, 11]; break;
|
||
case 11: sarRatio = [15, 11]; break;
|
||
case 12: sarRatio = [64, 33]; break;
|
||
case 13: sarRatio = [160, 99]; break;
|
||
case 14: sarRatio = [4, 3]; break;
|
||
case 15: sarRatio = [3, 2]; break;
|
||
case 16: sarRatio = [2, 1]; break;
|
||
case 255: {
|
||
sarRatio = [expGolombDecoder.readUnsignedByte() << 8 |
|
||
expGolombDecoder.readUnsignedByte(),
|
||
expGolombDecoder.readUnsignedByte() << 8 |
|
||
expGolombDecoder.readUnsignedByte() ];
|
||
break;
|
||
}
|
||
}
|
||
if (sarRatio) {
|
||
sarScale = sarRatio[0] / sarRatio[1];
|
||
}
|
||
}
|
||
}
|
||
return {
|
||
profileIdc: profileIdc,
|
||
levelIdc: levelIdc,
|
||
profileCompatibility: profileCompatibility,
|
||
width: Math.ceil((((picWidthInMbsMinus1 + 1) * 16) - frameCropLeftOffset * 2 - frameCropRightOffset * 2) * sarScale),
|
||
height: ((2 - frameMbsOnlyFlag) * (picHeightInMapUnitsMinus1 + 1) * 16) - (frameCropTopOffset * 2) - (frameCropBottomOffset * 2)
|
||
};
|
||
};
|
||
|
||
};
|
||
H264Stream.prototype = new Stream();
|
||
|
||
module.exports = {
|
||
H264Stream: H264Stream,
|
||
NalByteStream: NalByteStream
|
||
};
|
||
|
||
},{"../utils/exp-golomb.js":14,"../utils/stream.js":15}],3:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
var Stream = require('../utils/stream.js');
|
||
|
||
/**
|
||
* The final stage of the transmuxer that emits the flv tags
|
||
* for audio, video, and metadata. Also tranlates in time and
|
||
* outputs caption data and id3 cues.
|
||
*/
|
||
var CoalesceStream = function(options) {
|
||
// Number of Tracks per output segment
|
||
// If greater than 1, we combine multiple
|
||
// tracks into a single segment
|
||
this.numberOfTracks = 0;
|
||
this.metadataStream = options.metadataStream;
|
||
|
||
this.videoTags = [];
|
||
this.audioTags = [];
|
||
this.videoTrack = null;
|
||
this.audioTrack = null;
|
||
this.pendingCaptions = [];
|
||
this.pendingMetadata = [];
|
||
this.pendingTracks = 0;
|
||
this.processedTracks = 0;
|
||
|
||
CoalesceStream.prototype.init.call(this);
|
||
|
||
// Take output from multiple
|
||
this.push = function(output) {
|
||
// buffer incoming captions until the associated video segment
|
||
// finishes
|
||
if (output.text) {
|
||
return this.pendingCaptions.push(output);
|
||
}
|
||
// buffer incoming id3 tags until the final flush
|
||
if (output.frames) {
|
||
return this.pendingMetadata.push(output);
|
||
}
|
||
|
||
if (output.track.type === 'video') {
|
||
this.videoTrack = output.track;
|
||
this.videoTags = output.tags;
|
||
this.pendingTracks++;
|
||
}
|
||
if (output.track.type === 'audio') {
|
||
this.audioTrack = output.track;
|
||
this.audioTags = output.tags;
|
||
this.pendingTracks++;
|
||
}
|
||
};
|
||
};
|
||
|
||
CoalesceStream.prototype = new Stream();
|
||
CoalesceStream.prototype.flush = function(flushSource) {
|
||
var
|
||
id3,
|
||
caption,
|
||
i,
|
||
timelineStartPts,
|
||
event = {
|
||
tags: {},
|
||
captions: [],
|
||
captionStreams: {},
|
||
metadata: []
|
||
};
|
||
|
||
if (this.pendingTracks < this.numberOfTracks) {
|
||
if (flushSource !== 'VideoSegmentStream' &&
|
||
flushSource !== 'AudioSegmentStream') {
|
||
// Return because we haven't received a flush from a data-generating
|
||
// portion of the segment (meaning that we have only recieved meta-data
|
||
// or captions.)
|
||
return;
|
||
} else if (this.pendingTracks === 0) {
|
||
// In the case where we receive a flush without any data having been
|
||
// received we consider it an emitted track for the purposes of coalescing
|
||
// `done` events.
|
||
// We do this for the case where there is an audio and video track in the
|
||
// segment but no audio data. (seen in several playlists with alternate
|
||
// audio tracks and no audio present in the main TS segments.)
|
||
this.processedTracks++;
|
||
|
||
if (this.processedTracks < this.numberOfTracks) {
|
||
return;
|
||
}
|
||
}
|
||
}
|
||
|
||
this.processedTracks += this.pendingTracks;
|
||
this.pendingTracks = 0;
|
||
|
||
if (this.processedTracks < this.numberOfTracks) {
|
||
return;
|
||
}
|
||
|
||
if (this.videoTrack) {
|
||
timelineStartPts = this.videoTrack.timelineStartInfo.pts;
|
||
} else if (this.audioTrack) {
|
||
timelineStartPts = this.audioTrack.timelineStartInfo.pts;
|
||
}
|
||
|
||
event.tags.videoTags = this.videoTags;
|
||
event.tags.audioTags = this.audioTags;
|
||
|
||
// Translate caption PTS times into second offsets into the
|
||
// video timeline for the segment, and add track info
|
||
for (i = 0; i < this.pendingCaptions.length; i++) {
|
||
caption = this.pendingCaptions[i];
|
||
caption.startTime = caption.startPts - timelineStartPts;
|
||
caption.startTime /= 90e3;
|
||
caption.endTime = caption.endPts - timelineStartPts;
|
||
caption.endTime /= 90e3;
|
||
event.captionStreams[caption.stream] = true;
|
||
event.captions.push(caption);
|
||
}
|
||
|
||
// Translate ID3 frame PTS times into second offsets into the
|
||
// video timeline for the segment
|
||
for (i = 0; i < this.pendingMetadata.length; i++) {
|
||
id3 = this.pendingMetadata[i];
|
||
id3.cueTime = id3.pts - timelineStartPts;
|
||
id3.cueTime /= 90e3;
|
||
event.metadata.push(id3);
|
||
}
|
||
// We add this to every single emitted segment even though we only need
|
||
// it for the first
|
||
event.metadata.dispatchType = this.metadataStream.dispatchType;
|
||
|
||
// Reset stream state
|
||
this.videoTrack = null;
|
||
this.audioTrack = null;
|
||
this.videoTags = [];
|
||
this.audioTags = [];
|
||
this.pendingCaptions.length = 0;
|
||
this.pendingMetadata.length = 0;
|
||
this.pendingTracks = 0;
|
||
this.processedTracks = 0;
|
||
|
||
// Emit the final segment
|
||
this.trigger('data', event);
|
||
|
||
this.trigger('done');
|
||
};
|
||
|
||
module.exports = CoalesceStream;
|
||
|
||
},{"../utils/stream.js":15}],4:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
var FlvTag = require('./flv-tag.js');
|
||
|
||
// For information on the FLV format, see
|
||
// http://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf.
|
||
// Technically, this function returns the header and a metadata FLV tag
|
||
// if duration is greater than zero
|
||
// duration in seconds
|
||
// @return {object} the bytes of the FLV header as a Uint8Array
|
||
var getFlvHeader = function(duration, audio, video) { // :ByteArray {
|
||
var
|
||
headBytes = new Uint8Array(3 + 1 + 1 + 4),
|
||
head = new DataView(headBytes.buffer),
|
||
metadata,
|
||
result,
|
||
metadataLength;
|
||
|
||
// default arguments
|
||
duration = duration || 0;
|
||
audio = audio === undefined ? true : audio;
|
||
video = video === undefined ? true : video;
|
||
|
||
// signature
|
||
head.setUint8(0, 0x46); // 'F'
|
||
head.setUint8(1, 0x4c); // 'L'
|
||
head.setUint8(2, 0x56); // 'V'
|
||
|
||
// version
|
||
head.setUint8(3, 0x01);
|
||
|
||
// flags
|
||
head.setUint8(4, (audio ? 0x04 : 0x00) | (video ? 0x01 : 0x00));
|
||
|
||
// data offset, should be 9 for FLV v1
|
||
head.setUint32(5, headBytes.byteLength);
|
||
|
||
// init the first FLV tag
|
||
if (duration <= 0) {
|
||
// no duration available so just write the first field of the first
|
||
// FLV tag
|
||
result = new Uint8Array(headBytes.byteLength + 4);
|
||
result.set(headBytes);
|
||
result.set([0, 0, 0, 0], headBytes.byteLength);
|
||
return result;
|
||
}
|
||
|
||
// write out the duration metadata tag
|
||
metadata = new FlvTag(FlvTag.METADATA_TAG);
|
||
metadata.pts = metadata.dts = 0;
|
||
metadata.writeMetaDataDouble('duration', duration);
|
||
metadataLength = metadata.finalize().length;
|
||
result = new Uint8Array(headBytes.byteLength + metadataLength);
|
||
result.set(headBytes);
|
||
result.set(head.byteLength, metadataLength);
|
||
|
||
return result;
|
||
};
|
||
|
||
module.exports = getFlvHeader;
|
||
|
||
},{"./flv-tag.js":5}],5:[function(require,module,exports){
|
||
/**
|
||
* An object that stores the bytes of an FLV tag and methods for
|
||
* querying and manipulating that data.
|
||
* @see http://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf
|
||
*/
|
||
'use strict';
|
||
|
||
var FlvTag;
|
||
|
||
// (type:uint, extraData:Boolean = false) extends ByteArray
|
||
FlvTag = function(type, extraData) {
|
||
var
|
||
// Counter if this is a metadata tag, nal start marker if this is a video
|
||
// tag. unused if this is an audio tag
|
||
adHoc = 0, // :uint
|
||
|
||
// The default size is 16kb but this is not enough to hold iframe
|
||
// data and the resizing algorithm costs a bit so we create a larger
|
||
// starting buffer for video tags
|
||
bufferStartSize = 16384,
|
||
|
||
// checks whether the FLV tag has enough capacity to accept the proposed
|
||
// write and re-allocates the internal buffers if necessary
|
||
prepareWrite = function(flv, count) {
|
||
var
|
||
bytes,
|
||
minLength = flv.position + count;
|
||
if (minLength < flv.bytes.byteLength) {
|
||
// there's enough capacity so do nothing
|
||
return;
|
||
}
|
||
|
||
// allocate a new buffer and copy over the data that will not be modified
|
||
bytes = new Uint8Array(minLength * 2);
|
||
bytes.set(flv.bytes.subarray(0, flv.position), 0);
|
||
flv.bytes = bytes;
|
||
flv.view = new DataView(flv.bytes.buffer);
|
||
},
|
||
|
||
// commonly used metadata properties
|
||
widthBytes = FlvTag.widthBytes || new Uint8Array('width'.length),
|
||
heightBytes = FlvTag.heightBytes || new Uint8Array('height'.length),
|
||
videocodecidBytes = FlvTag.videocodecidBytes || new Uint8Array('videocodecid'.length),
|
||
i;
|
||
|
||
if (!FlvTag.widthBytes) {
|
||
// calculating the bytes of common metadata names ahead of time makes the
|
||
// corresponding writes faster because we don't have to loop over the
|
||
// characters
|
||
// re-test with test/perf.html if you're planning on changing this
|
||
for (i = 0; i < 'width'.length; i++) {
|
||
widthBytes[i] = 'width'.charCodeAt(i);
|
||
}
|
||
for (i = 0; i < 'height'.length; i++) {
|
||
heightBytes[i] = 'height'.charCodeAt(i);
|
||
}
|
||
for (i = 0; i < 'videocodecid'.length; i++) {
|
||
videocodecidBytes[i] = 'videocodecid'.charCodeAt(i);
|
||
}
|
||
|
||
FlvTag.widthBytes = widthBytes;
|
||
FlvTag.heightBytes = heightBytes;
|
||
FlvTag.videocodecidBytes = videocodecidBytes;
|
||
}
|
||
|
||
this.keyFrame = false; // :Boolean
|
||
|
||
switch (type) {
|
||
case FlvTag.VIDEO_TAG:
|
||
this.length = 16;
|
||
// Start the buffer at 256k
|
||
bufferStartSize *= 6;
|
||
break;
|
||
case FlvTag.AUDIO_TAG:
|
||
this.length = 13;
|
||
this.keyFrame = true;
|
||
break;
|
||
case FlvTag.METADATA_TAG:
|
||
this.length = 29;
|
||
this.keyFrame = true;
|
||
break;
|
||
default:
|
||
throw new Error('Unknown FLV tag type');
|
||
}
|
||
|
||
this.bytes = new Uint8Array(bufferStartSize);
|
||
this.view = new DataView(this.bytes.buffer);
|
||
this.bytes[0] = type;
|
||
this.position = this.length;
|
||
this.keyFrame = extraData; // Defaults to false
|
||
|
||
// presentation timestamp
|
||
this.pts = 0;
|
||
// decoder timestamp
|
||
this.dts = 0;
|
||
|
||
// ByteArray#writeBytes(bytes:ByteArray, offset:uint = 0, length:uint = 0)
|
||
this.writeBytes = function(bytes, offset, length) {
|
||
var
|
||
start = offset || 0,
|
||
end;
|
||
length = length || bytes.byteLength;
|
||
end = start + length;
|
||
|
||
prepareWrite(this, length);
|
||
this.bytes.set(bytes.subarray(start, end), this.position);
|
||
|
||
this.position += length;
|
||
this.length = Math.max(this.length, this.position);
|
||
};
|
||
|
||
// ByteArray#writeByte(value:int):void
|
||
this.writeByte = function(byte) {
|
||
prepareWrite(this, 1);
|
||
this.bytes[this.position] = byte;
|
||
this.position++;
|
||
this.length = Math.max(this.length, this.position);
|
||
};
|
||
|
||
// ByteArray#writeShort(value:int):void
|
||
this.writeShort = function(short) {
|
||
prepareWrite(this, 2);
|
||
this.view.setUint16(this.position, short);
|
||
this.position += 2;
|
||
this.length = Math.max(this.length, this.position);
|
||
};
|
||
|
||
// Negative index into array
|
||
// (pos:uint):int
|
||
this.negIndex = function(pos) {
|
||
return this.bytes[this.length - pos];
|
||
};
|
||
|
||
// The functions below ONLY work when this[0] == VIDEO_TAG.
|
||
// We are not going to check for that because we dont want the overhead
|
||
// (nal:ByteArray = null):int
|
||
this.nalUnitSize = function() {
|
||
if (adHoc === 0) {
|
||
return 0;
|
||
}
|
||
|
||
return this.length - (adHoc + 4);
|
||
};
|
||
|
||
this.startNalUnit = function() {
|
||
// remember position and add 4 bytes
|
||
if (adHoc > 0) {
|
||
throw new Error('Attempted to create new NAL wihout closing the old one');
|
||
}
|
||
|
||
// reserve 4 bytes for nal unit size
|
||
adHoc = this.length;
|
||
this.length += 4;
|
||
this.position = this.length;
|
||
};
|
||
|
||
// (nal:ByteArray = null):void
|
||
this.endNalUnit = function(nalContainer) {
|
||
var
|
||
nalStart, // :uint
|
||
nalLength; // :uint
|
||
|
||
// Rewind to the marker and write the size
|
||
if (this.length === adHoc + 4) {
|
||
// we started a nal unit, but didnt write one, so roll back the 4 byte size value
|
||
this.length -= 4;
|
||
} else if (adHoc > 0) {
|
||
nalStart = adHoc + 4;
|
||
nalLength = this.length - nalStart;
|
||
|
||
this.position = adHoc;
|
||
this.view.setUint32(this.position, nalLength);
|
||
this.position = this.length;
|
||
|
||
if (nalContainer) {
|
||
// Add the tag to the NAL unit
|
||
nalContainer.push(this.bytes.subarray(nalStart, nalStart + nalLength));
|
||
}
|
||
}
|
||
|
||
adHoc = 0;
|
||
};
|
||
|
||
/**
|
||
* Write out a 64-bit floating point valued metadata property. This method is
|
||
* called frequently during a typical parse and needs to be fast.
|
||
*/
|
||
// (key:String, val:Number):void
|
||
this.writeMetaDataDouble = function(key, val) {
|
||
var i;
|
||
prepareWrite(this, 2 + key.length + 9);
|
||
|
||
// write size of property name
|
||
this.view.setUint16(this.position, key.length);
|
||
this.position += 2;
|
||
|
||
// this next part looks terrible but it improves parser throughput by
|
||
// 10kB/s in my testing
|
||
|
||
// write property name
|
||
if (key === 'width') {
|
||
this.bytes.set(widthBytes, this.position);
|
||
this.position += 5;
|
||
} else if (key === 'height') {
|
||
this.bytes.set(heightBytes, this.position);
|
||
this.position += 6;
|
||
} else if (key === 'videocodecid') {
|
||
this.bytes.set(videocodecidBytes, this.position);
|
||
this.position += 12;
|
||
} else {
|
||
for (i = 0; i < key.length; i++) {
|
||
this.bytes[this.position] = key.charCodeAt(i);
|
||
this.position++;
|
||
}
|
||
}
|
||
|
||
// skip null byte
|
||
this.position++;
|
||
|
||
// write property value
|
||
this.view.setFloat64(this.position, val);
|
||
this.position += 8;
|
||
|
||
// update flv tag length
|
||
this.length = Math.max(this.length, this.position);
|
||
++adHoc;
|
||
};
|
||
|
||
// (key:String, val:Boolean):void
|
||
this.writeMetaDataBoolean = function(key, val) {
|
||
var i;
|
||
prepareWrite(this, 2);
|
||
this.view.setUint16(this.position, key.length);
|
||
this.position += 2;
|
||
for (i = 0; i < key.length; i++) {
|
||
// if key.charCodeAt(i) >= 255, handle error
|
||
prepareWrite(this, 1);
|
||
this.bytes[this.position] = key.charCodeAt(i);
|
||
this.position++;
|
||
}
|
||
prepareWrite(this, 2);
|
||
this.view.setUint8(this.position, 0x01);
|
||
this.position++;
|
||
this.view.setUint8(this.position, val ? 0x01 : 0x00);
|
||
this.position++;
|
||
this.length = Math.max(this.length, this.position);
|
||
++adHoc;
|
||
};
|
||
|
||
// ():ByteArray
|
||
this.finalize = function() {
|
||
var
|
||
dtsDelta, // :int
|
||
len; // :int
|
||
|
||
switch (this.bytes[0]) {
|
||
// Video Data
|
||
case FlvTag.VIDEO_TAG:
|
||
// We only support AVC, 1 = key frame (for AVC, a seekable
|
||
// frame), 2 = inter frame (for AVC, a non-seekable frame)
|
||
this.bytes[11] = ((this.keyFrame || extraData) ? 0x10 : 0x20) | 0x07;
|
||
this.bytes[12] = extraData ? 0x00 : 0x01;
|
||
|
||
dtsDelta = this.pts - this.dts;
|
||
this.bytes[13] = (dtsDelta & 0x00FF0000) >>> 16;
|
||
this.bytes[14] = (dtsDelta & 0x0000FF00) >>> 8;
|
||
this.bytes[15] = (dtsDelta & 0x000000FF) >>> 0;
|
||
break;
|
||
|
||
case FlvTag.AUDIO_TAG:
|
||
this.bytes[11] = 0xAF; // 44 kHz, 16-bit stereo
|
||
this.bytes[12] = extraData ? 0x00 : 0x01;
|
||
break;
|
||
|
||
case FlvTag.METADATA_TAG:
|
||
this.position = 11;
|
||
this.view.setUint8(this.position, 0x02); // String type
|
||
this.position++;
|
||
this.view.setUint16(this.position, 0x0A); // 10 Bytes
|
||
this.position += 2;
|
||
// set "onMetaData"
|
||
this.bytes.set([0x6f, 0x6e, 0x4d, 0x65,
|
||
0x74, 0x61, 0x44, 0x61,
|
||
0x74, 0x61], this.position);
|
||
this.position += 10;
|
||
this.bytes[this.position] = 0x08; // Array type
|
||
this.position++;
|
||
this.view.setUint32(this.position, adHoc);
|
||
this.position = this.length;
|
||
this.bytes.set([0, 0, 9], this.position);
|
||
this.position += 3; // End Data Tag
|
||
this.length = this.position;
|
||
break;
|
||
}
|
||
|
||
len = this.length - 11;
|
||
|
||
// write the DataSize field
|
||
this.bytes[ 1] = (len & 0x00FF0000) >>> 16;
|
||
this.bytes[ 2] = (len & 0x0000FF00) >>> 8;
|
||
this.bytes[ 3] = (len & 0x000000FF) >>> 0;
|
||
// write the Timestamp
|
||
this.bytes[ 4] = (this.dts & 0x00FF0000) >>> 16;
|
||
this.bytes[ 5] = (this.dts & 0x0000FF00) >>> 8;
|
||
this.bytes[ 6] = (this.dts & 0x000000FF) >>> 0;
|
||
this.bytes[ 7] = (this.dts & 0xFF000000) >>> 24;
|
||
// write the StreamID
|
||
this.bytes[ 8] = 0;
|
||
this.bytes[ 9] = 0;
|
||
this.bytes[10] = 0;
|
||
|
||
// Sometimes we're at the end of the view and have one slot to write a
|
||
// uint32, so, prepareWrite of count 4, since, view is uint8
|
||
prepareWrite(this, 4);
|
||
this.view.setUint32(this.length, this.length);
|
||
this.length += 4;
|
||
this.position += 4;
|
||
|
||
// trim down the byte buffer to what is actually being used
|
||
this.bytes = this.bytes.subarray(0, this.length);
|
||
this.frameTime = FlvTag.frameTime(this.bytes);
|
||
// if bytes.bytelength isn't equal to this.length, handle error
|
||
return this;
|
||
};
|
||
};
|
||
|
||
FlvTag.AUDIO_TAG = 0x08; // == 8, :uint
|
||
FlvTag.VIDEO_TAG = 0x09; // == 9, :uint
|
||
FlvTag.METADATA_TAG = 0x12; // == 18, :uint
|
||
|
||
// (tag:ByteArray):Boolean {
|
||
FlvTag.isAudioFrame = function(tag) {
|
||
return FlvTag.AUDIO_TAG === tag[0];
|
||
};
|
||
|
||
// (tag:ByteArray):Boolean {
|
||
FlvTag.isVideoFrame = function(tag) {
|
||
return FlvTag.VIDEO_TAG === tag[0];
|
||
};
|
||
|
||
// (tag:ByteArray):Boolean {
|
||
FlvTag.isMetaData = function(tag) {
|
||
return FlvTag.METADATA_TAG === tag[0];
|
||
};
|
||
|
||
// (tag:ByteArray):Boolean {
|
||
FlvTag.isKeyFrame = function(tag) {
|
||
if (FlvTag.isVideoFrame(tag)) {
|
||
return tag[11] === 0x17;
|
||
}
|
||
|
||
if (FlvTag.isAudioFrame(tag)) {
|
||
return true;
|
||
}
|
||
|
||
if (FlvTag.isMetaData(tag)) {
|
||
return true;
|
||
}
|
||
|
||
return false;
|
||
};
|
||
|
||
// (tag:ByteArray):uint {
|
||
FlvTag.frameTime = function(tag) {
|
||
var pts = tag[ 4] << 16; // :uint
|
||
pts |= tag[ 5] << 8;
|
||
pts |= tag[ 6] << 0;
|
||
pts |= tag[ 7] << 24;
|
||
return pts;
|
||
};
|
||
|
||
module.exports = FlvTag;
|
||
|
||
},{}],6:[function(require,module,exports){
|
||
module.exports = {
|
||
tag: require('./flv-tag'),
|
||
Transmuxer: require('./transmuxer'),
|
||
getFlvHeader: require('./flv-header')
|
||
};
|
||
|
||
},{"./flv-header":4,"./flv-tag":5,"./transmuxer":8}],7:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
var TagList = function() {
|
||
var self = this;
|
||
|
||
this.list = [];
|
||
|
||
this.push = function(tag) {
|
||
this.list.push({
|
||
bytes: tag.bytes,
|
||
dts: tag.dts,
|
||
pts: tag.pts,
|
||
keyFrame: tag.keyFrame,
|
||
metaDataTag: tag.metaDataTag
|
||
});
|
||
};
|
||
|
||
Object.defineProperty(this, 'length', {
|
||
get: function() {
|
||
return self.list.length;
|
||
}
|
||
});
|
||
};
|
||
|
||
module.exports = TagList;
|
||
|
||
},{}],8:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
var Stream = require('../utils/stream.js');
|
||
var FlvTag = require('./flv-tag.js');
|
||
var m2ts = require('../m2ts/m2ts.js');
|
||
var AdtsStream = require('../codecs/adts.js');
|
||
var H264Stream = require('../codecs/h264').H264Stream;
|
||
var CoalesceStream = require('./coalesce-stream.js');
|
||
var TagList = require('./tag-list.js');
|
||
|
||
var
|
||
Transmuxer,
|
||
VideoSegmentStream,
|
||
AudioSegmentStream,
|
||
collectTimelineInfo,
|
||
metaDataTag,
|
||
extraDataTag;
|
||
|
||
/**
|
||
* Store information about the start and end of the tracka and the
|
||
* duration for each frame/sample we process in order to calculate
|
||
* the baseMediaDecodeTime
|
||
*/
|
||
collectTimelineInfo = function(track, data) {
|
||
if (typeof data.pts === 'number') {
|
||
if (track.timelineStartInfo.pts === undefined) {
|
||
track.timelineStartInfo.pts = data.pts;
|
||
} else {
|
||
track.timelineStartInfo.pts =
|
||
Math.min(track.timelineStartInfo.pts, data.pts);
|
||
}
|
||
}
|
||
|
||
if (typeof data.dts === 'number') {
|
||
if (track.timelineStartInfo.dts === undefined) {
|
||
track.timelineStartInfo.dts = data.dts;
|
||
} else {
|
||
track.timelineStartInfo.dts =
|
||
Math.min(track.timelineStartInfo.dts, data.dts);
|
||
}
|
||
}
|
||
};
|
||
|
||
metaDataTag = function(track, pts) {
|
||
var
|
||
tag = new FlvTag(FlvTag.METADATA_TAG); // :FlvTag
|
||
|
||
tag.dts = pts;
|
||
tag.pts = pts;
|
||
|
||
tag.writeMetaDataDouble('videocodecid', 7);
|
||
tag.writeMetaDataDouble('width', track.width);
|
||
tag.writeMetaDataDouble('height', track.height);
|
||
|
||
return tag;
|
||
};
|
||
|
||
extraDataTag = function(track, pts) {
|
||
var
|
||
i,
|
||
tag = new FlvTag(FlvTag.VIDEO_TAG, true);
|
||
|
||
tag.dts = pts;
|
||
tag.pts = pts;
|
||
|
||
tag.writeByte(0x01);// version
|
||
tag.writeByte(track.profileIdc);// profile
|
||
tag.writeByte(track.profileCompatibility);// compatibility
|
||
tag.writeByte(track.levelIdc);// level
|
||
tag.writeByte(0xFC | 0x03); // reserved (6 bits), NULA length size - 1 (2 bits)
|
||
tag.writeByte(0xE0 | 0x01); // reserved (3 bits), num of SPS (5 bits)
|
||
tag.writeShort(track.sps[0].length); // data of SPS
|
||
tag.writeBytes(track.sps[0]); // SPS
|
||
|
||
tag.writeByte(track.pps.length); // num of PPS (will there ever be more that 1 PPS?)
|
||
for (i = 0; i < track.pps.length; ++i) {
|
||
tag.writeShort(track.pps[i].length); // 2 bytes for length of PPS
|
||
tag.writeBytes(track.pps[i]); // data of PPS
|
||
}
|
||
|
||
return tag;
|
||
};
|
||
|
||
/**
|
||
* Constructs a single-track, media segment from AAC data
|
||
* events. The output of this stream can be fed to flash.
|
||
*/
|
||
AudioSegmentStream = function(track) {
|
||
var
|
||
adtsFrames = [],
|
||
videoKeyFrames = [],
|
||
oldExtraData;
|
||
|
||
AudioSegmentStream.prototype.init.call(this);
|
||
|
||
this.push = function(data) {
|
||
collectTimelineInfo(track, data);
|
||
|
||
if (track) {
|
||
track.audioobjecttype = data.audioobjecttype;
|
||
track.channelcount = data.channelcount;
|
||
track.samplerate = data.samplerate;
|
||
track.samplingfrequencyindex = data.samplingfrequencyindex;
|
||
track.samplesize = data.samplesize;
|
||
track.extraData = (track.audioobjecttype << 11) |
|
||
(track.samplingfrequencyindex << 7) |
|
||
(track.channelcount << 3);
|
||
}
|
||
|
||
data.pts = Math.round(data.pts / 90);
|
||
data.dts = Math.round(data.dts / 90);
|
||
|
||
// buffer audio data until end() is called
|
||
adtsFrames.push(data);
|
||
};
|
||
|
||
this.flush = function() {
|
||
var currentFrame, adtsFrame, lastMetaPts, tags = new TagList();
|
||
// return early if no audio data has been observed
|
||
if (adtsFrames.length === 0) {
|
||
this.trigger('done', 'AudioSegmentStream');
|
||
return;
|
||
}
|
||
|
||
lastMetaPts = -Infinity;
|
||
|
||
while (adtsFrames.length) {
|
||
currentFrame = adtsFrames.shift();
|
||
|
||
// write out a metadata frame at every video key frame
|
||
if (videoKeyFrames.length && currentFrame.pts >= videoKeyFrames[0]) {
|
||
lastMetaPts = videoKeyFrames.shift();
|
||
this.writeMetaDataTags(tags, lastMetaPts);
|
||
}
|
||
|
||
// also write out metadata tags every 1 second so that the decoder
|
||
// is re-initialized quickly after seeking into a different
|
||
// audio configuration.
|
||
if (track.extraData !== oldExtraData || currentFrame.pts - lastMetaPts >= 1000) {
|
||
this.writeMetaDataTags(tags, currentFrame.pts);
|
||
oldExtraData = track.extraData;
|
||
lastMetaPts = currentFrame.pts;
|
||
}
|
||
|
||
adtsFrame = new FlvTag(FlvTag.AUDIO_TAG);
|
||
adtsFrame.pts = currentFrame.pts;
|
||
adtsFrame.dts = currentFrame.dts;
|
||
|
||
adtsFrame.writeBytes(currentFrame.data);
|
||
|
||
tags.push(adtsFrame.finalize());
|
||
}
|
||
|
||
videoKeyFrames.length = 0;
|
||
oldExtraData = null;
|
||
this.trigger('data', {track: track, tags: tags.list});
|
||
|
||
this.trigger('done', 'AudioSegmentStream');
|
||
};
|
||
|
||
this.writeMetaDataTags = function(tags, pts) {
|
||
var adtsFrame;
|
||
|
||
adtsFrame = new FlvTag(FlvTag.METADATA_TAG);
|
||
// For audio, DTS is always the same as PTS. We want to set the DTS
|
||
// however so we can compare with video DTS to determine approximate
|
||
// packet order
|
||
adtsFrame.pts = pts;
|
||
adtsFrame.dts = pts;
|
||
|
||
// AAC is always 10
|
||
adtsFrame.writeMetaDataDouble('audiocodecid', 10);
|
||
adtsFrame.writeMetaDataBoolean('stereo', track.channelcount === 2);
|
||
adtsFrame.writeMetaDataDouble('audiosamplerate', track.samplerate);
|
||
// Is AAC always 16 bit?
|
||
adtsFrame.writeMetaDataDouble('audiosamplesize', 16);
|
||
|
||
tags.push(adtsFrame.finalize());
|
||
|
||
adtsFrame = new FlvTag(FlvTag.AUDIO_TAG, true);
|
||
// For audio, DTS is always the same as PTS. We want to set the DTS
|
||
// however so we can compare with video DTS to determine approximate
|
||
// packet order
|
||
adtsFrame.pts = pts;
|
||
adtsFrame.dts = pts;
|
||
|
||
adtsFrame.view.setUint16(adtsFrame.position, track.extraData);
|
||
adtsFrame.position += 2;
|
||
adtsFrame.length = Math.max(adtsFrame.length, adtsFrame.position);
|
||
|
||
tags.push(adtsFrame.finalize());
|
||
};
|
||
|
||
this.onVideoKeyFrame = function(pts) {
|
||
videoKeyFrames.push(pts);
|
||
};
|
||
};
|
||
AudioSegmentStream.prototype = new Stream();
|
||
|
||
/**
|
||
* Store FlvTags for the h264 stream
|
||
* @param track {object} track metadata configuration
|
||
*/
|
||
VideoSegmentStream = function(track) {
|
||
var
|
||
nalUnits = [],
|
||
config,
|
||
h264Frame;
|
||
VideoSegmentStream.prototype.init.call(this);
|
||
|
||
this.finishFrame = function(tags, frame) {
|
||
if (!frame) {
|
||
return;
|
||
}
|
||
// Check if keyframe and the length of tags.
|
||
// This makes sure we write metadata on the first frame of a segment.
|
||
if (config && track && track.newMetadata &&
|
||
(frame.keyFrame || tags.length === 0)) {
|
||
// Push extra data on every IDR frame in case we did a stream change + seek
|
||
var metaTag = metaDataTag(config, frame.dts).finalize();
|
||
var extraTag = extraDataTag(track, frame.dts).finalize();
|
||
|
||
metaTag.metaDataTag = extraTag.metaDataTag = true;
|
||
|
||
tags.push(metaTag);
|
||
tags.push(extraTag);
|
||
track.newMetadata = false;
|
||
|
||
this.trigger('keyframe', frame.dts);
|
||
}
|
||
|
||
frame.endNalUnit();
|
||
tags.push(frame.finalize());
|
||
h264Frame = null;
|
||
};
|
||
|
||
this.push = function(data) {
|
||
collectTimelineInfo(track, data);
|
||
|
||
data.pts = Math.round(data.pts / 90);
|
||
data.dts = Math.round(data.dts / 90);
|
||
|
||
// buffer video until flush() is called
|
||
nalUnits.push(data);
|
||
};
|
||
|
||
this.flush = function() {
|
||
var
|
||
currentNal,
|
||
tags = new TagList();
|
||
|
||
// Throw away nalUnits at the start of the byte stream until we find
|
||
// the first AUD
|
||
while (nalUnits.length) {
|
||
if (nalUnits[0].nalUnitType === 'access_unit_delimiter_rbsp') {
|
||
break;
|
||
}
|
||
nalUnits.shift();
|
||
}
|
||
|
||
// return early if no video data has been observed
|
||
if (nalUnits.length === 0) {
|
||
this.trigger('done', 'VideoSegmentStream');
|
||
return;
|
||
}
|
||
|
||
while (nalUnits.length) {
|
||
currentNal = nalUnits.shift();
|
||
|
||
// record the track config
|
||
if (currentNal.nalUnitType === 'seq_parameter_set_rbsp') {
|
||
track.newMetadata = true;
|
||
config = currentNal.config;
|
||
track.width = config.width;
|
||
track.height = config.height;
|
||
track.sps = [currentNal.data];
|
||
track.profileIdc = config.profileIdc;
|
||
track.levelIdc = config.levelIdc;
|
||
track.profileCompatibility = config.profileCompatibility;
|
||
h264Frame.endNalUnit();
|
||
} else if (currentNal.nalUnitType === 'pic_parameter_set_rbsp') {
|
||
track.newMetadata = true;
|
||
track.pps = [currentNal.data];
|
||
h264Frame.endNalUnit();
|
||
} else if (currentNal.nalUnitType === 'access_unit_delimiter_rbsp') {
|
||
if (h264Frame) {
|
||
this.finishFrame(tags, h264Frame);
|
||
}
|
||
h264Frame = new FlvTag(FlvTag.VIDEO_TAG);
|
||
h264Frame.pts = currentNal.pts;
|
||
h264Frame.dts = currentNal.dts;
|
||
} else {
|
||
if (currentNal.nalUnitType === 'slice_layer_without_partitioning_rbsp_idr') {
|
||
// the current sample is a key frame
|
||
h264Frame.keyFrame = true;
|
||
}
|
||
h264Frame.endNalUnit();
|
||
}
|
||
h264Frame.startNalUnit();
|
||
h264Frame.writeBytes(currentNal.data);
|
||
}
|
||
if (h264Frame) {
|
||
this.finishFrame(tags, h264Frame);
|
||
}
|
||
|
||
this.trigger('data', {track: track, tags: tags.list});
|
||
|
||
// Continue with the flush process now
|
||
this.trigger('done', 'VideoSegmentStream');
|
||
};
|
||
};
|
||
|
||
VideoSegmentStream.prototype = new Stream();
|
||
|
||
/**
|
||
* An object that incrementally transmuxes MPEG2 Trasport Stream
|
||
* chunks into an FLV.
|
||
*/
|
||
Transmuxer = function(options) {
|
||
var
|
||
self = this,
|
||
|
||
packetStream, parseStream, elementaryStream,
|
||
videoTimestampRolloverStream, audioTimestampRolloverStream,
|
||
timedMetadataTimestampRolloverStream,
|
||
adtsStream, h264Stream,
|
||
videoSegmentStream, audioSegmentStream, captionStream,
|
||
coalesceStream;
|
||
|
||
Transmuxer.prototype.init.call(this);
|
||
|
||
options = options || {};
|
||
|
||
// expose the metadata stream
|
||
this.metadataStream = new m2ts.MetadataStream();
|
||
|
||
options.metadataStream = this.metadataStream;
|
||
|
||
// set up the parsing pipeline
|
||
packetStream = new m2ts.TransportPacketStream();
|
||
parseStream = new m2ts.TransportParseStream();
|
||
elementaryStream = new m2ts.ElementaryStream();
|
||
videoTimestampRolloverStream = new m2ts.TimestampRolloverStream('video');
|
||
audioTimestampRolloverStream = new m2ts.TimestampRolloverStream('audio');
|
||
timedMetadataTimestampRolloverStream = new m2ts.TimestampRolloverStream('timed-metadata');
|
||
|
||
adtsStream = new AdtsStream();
|
||
h264Stream = new H264Stream();
|
||
coalesceStream = new CoalesceStream(options);
|
||
|
||
// disassemble MPEG2-TS packets into elementary streams
|
||
packetStream
|
||
.pipe(parseStream)
|
||
.pipe(elementaryStream);
|
||
|
||
// !!THIS ORDER IS IMPORTANT!!
|
||
// demux the streams
|
||
elementaryStream
|
||
.pipe(videoTimestampRolloverStream)
|
||
.pipe(h264Stream);
|
||
elementaryStream
|
||
.pipe(audioTimestampRolloverStream)
|
||
.pipe(adtsStream);
|
||
|
||
elementaryStream
|
||
.pipe(timedMetadataTimestampRolloverStream)
|
||
.pipe(this.metadataStream)
|
||
.pipe(coalesceStream);
|
||
// if CEA-708 parsing is available, hook up a caption stream
|
||
captionStream = new m2ts.CaptionStream();
|
||
h264Stream.pipe(captionStream)
|
||
.pipe(coalesceStream);
|
||
|
||
// hook up the segment streams once track metadata is delivered
|
||
elementaryStream.on('data', function(data) {
|
||
var i, videoTrack, audioTrack;
|
||
|
||
if (data.type === 'metadata') {
|
||
i = data.tracks.length;
|
||
|
||
// scan the tracks listed in the metadata
|
||
while (i--) {
|
||
if (data.tracks[i].type === 'video') {
|
||
videoTrack = data.tracks[i];
|
||
} else if (data.tracks[i].type === 'audio') {
|
||
audioTrack = data.tracks[i];
|
||
}
|
||
}
|
||
|
||
// hook up the video segment stream to the first track with h264 data
|
||
if (videoTrack && !videoSegmentStream) {
|
||
coalesceStream.numberOfTracks++;
|
||
videoSegmentStream = new VideoSegmentStream(videoTrack);
|
||
|
||
// Set up the final part of the video pipeline
|
||
h264Stream
|
||
.pipe(videoSegmentStream)
|
||
.pipe(coalesceStream);
|
||
}
|
||
|
||
if (audioTrack && !audioSegmentStream) {
|
||
// hook up the audio segment stream to the first track with aac data
|
||
coalesceStream.numberOfTracks++;
|
||
audioSegmentStream = new AudioSegmentStream(audioTrack);
|
||
|
||
// Set up the final part of the audio pipeline
|
||
adtsStream
|
||
.pipe(audioSegmentStream)
|
||
.pipe(coalesceStream);
|
||
|
||
if (videoSegmentStream) {
|
||
videoSegmentStream.on('keyframe', audioSegmentStream.onVideoKeyFrame);
|
||
}
|
||
}
|
||
}
|
||
});
|
||
|
||
// feed incoming data to the front of the parsing pipeline
|
||
this.push = function(data) {
|
||
packetStream.push(data);
|
||
};
|
||
|
||
// flush any buffered data
|
||
this.flush = function() {
|
||
// Start at the top of the pipeline and flush all pending work
|
||
packetStream.flush();
|
||
};
|
||
|
||
// Caption data has to be reset when seeking outside buffered range
|
||
this.resetCaptions = function() {
|
||
captionStream.reset();
|
||
};
|
||
|
||
// Re-emit any data coming from the coalesce stream to the outside world
|
||
coalesceStream.on('data', function(event) {
|
||
self.trigger('data', event);
|
||
});
|
||
|
||
// Let the consumer know we have finished flushing the entire pipeline
|
||
coalesceStream.on('done', function() {
|
||
self.trigger('done');
|
||
});
|
||
};
|
||
Transmuxer.prototype = new Stream();
|
||
|
||
// forward compatibility
|
||
module.exports = Transmuxer;
|
||
|
||
},{"../codecs/adts.js":1,"../codecs/h264":2,"../m2ts/m2ts.js":10,"../utils/stream.js":15,"./coalesce-stream.js":3,"./flv-tag.js":5,"./tag-list.js":7}],9:[function(require,module,exports){
|
||
/**
|
||
* mux.js
|
||
*
|
||
* Copyright (c) 2015 Brightcove
|
||
* All rights reserved.
|
||
*
|
||
* Reads in-band caption information from a video elementary
|
||
* stream. Captions must follow the CEA-708 standard for injection
|
||
* into an MPEG-2 transport streams.
|
||
* @see https://en.wikipedia.org/wiki/CEA-708
|
||
* @see https://www.gpo.gov/fdsys/pkg/CFR-2007-title47-vol1/pdf/CFR-2007-title47-vol1-sec15-119.pdf
|
||
*/
|
||
|
||
'use strict';
|
||
|
||
// -----------------
|
||
// Link To Transport
|
||
// -----------------
|
||
|
||
// Supplemental enhancement information (SEI) NAL units have a
|
||
// payload type field to indicate how they are to be
|
||
// interpreted. CEAS-708 caption content is always transmitted with
|
||
// payload type 0x04.
|
||
var USER_DATA_REGISTERED_ITU_T_T35 = 4,
|
||
RBSP_TRAILING_BITS = 128,
|
||
Stream = require('../utils/stream');
|
||
|
||
/**
|
||
* Parse a supplemental enhancement information (SEI) NAL unit.
|
||
* Stops parsing once a message of type ITU T T35 has been found.
|
||
*
|
||
* @param bytes {Uint8Array} the bytes of a SEI NAL unit
|
||
* @return {object} the parsed SEI payload
|
||
* @see Rec. ITU-T H.264, 7.3.2.3.1
|
||
*/
|
||
var parseSei = function(bytes) {
|
||
var
|
||
i = 0,
|
||
result = {
|
||
payloadType: -1,
|
||
payloadSize: 0
|
||
},
|
||
payloadType = 0,
|
||
payloadSize = 0;
|
||
|
||
// go through the sei_rbsp parsing each each individual sei_message
|
||
while (i < bytes.byteLength) {
|
||
// stop once we have hit the end of the sei_rbsp
|
||
if (bytes[i] === RBSP_TRAILING_BITS) {
|
||
break;
|
||
}
|
||
|
||
// Parse payload type
|
||
while (bytes[i] === 0xFF) {
|
||
payloadType += 255;
|
||
i++;
|
||
}
|
||
payloadType += bytes[i++];
|
||
|
||
// Parse payload size
|
||
while (bytes[i] === 0xFF) {
|
||
payloadSize += 255;
|
||
i++;
|
||
}
|
||
payloadSize += bytes[i++];
|
||
|
||
// this sei_message is a 608/708 caption so save it and break
|
||
// there can only ever be one caption message in a frame's sei
|
||
if (!result.payload && payloadType === USER_DATA_REGISTERED_ITU_T_T35) {
|
||
result.payloadType = payloadType;
|
||
result.payloadSize = payloadSize;
|
||
result.payload = bytes.subarray(i, i + payloadSize);
|
||
break;
|
||
}
|
||
|
||
// skip the payload and parse the next message
|
||
i += payloadSize;
|
||
payloadType = 0;
|
||
payloadSize = 0;
|
||
}
|
||
|
||
return result;
|
||
};
|
||
|
||
// see ANSI/SCTE 128-1 (2013), section 8.1
|
||
var parseUserData = function(sei) {
|
||
// itu_t_t35_contry_code must be 181 (United States) for
|
||
// captions
|
||
if (sei.payload[0] !== 181) {
|
||
return null;
|
||
}
|
||
|
||
// itu_t_t35_provider_code should be 49 (ATSC) for captions
|
||
if (((sei.payload[1] << 8) | sei.payload[2]) !== 49) {
|
||
return null;
|
||
}
|
||
|
||
// the user_identifier should be "GA94" to indicate ATSC1 data
|
||
if (String.fromCharCode(sei.payload[3],
|
||
sei.payload[4],
|
||
sei.payload[5],
|
||
sei.payload[6]) !== 'GA94') {
|
||
return null;
|
||
}
|
||
|
||
// finally, user_data_type_code should be 0x03 for caption data
|
||
if (sei.payload[7] !== 0x03) {
|
||
return null;
|
||
}
|
||
|
||
// return the user_data_type_structure and strip the trailing
|
||
// marker bits
|
||
return sei.payload.subarray(8, sei.payload.length - 1);
|
||
};
|
||
|
||
// see CEA-708-D, section 4.4
|
||
var parseCaptionPackets = function(pts, userData) {
|
||
var results = [], i, count, offset, data;
|
||
|
||
// if this is just filler, return immediately
|
||
if (!(userData[0] & 0x40)) {
|
||
return results;
|
||
}
|
||
|
||
// parse out the cc_data_1 and cc_data_2 fields
|
||
count = userData[0] & 0x1f;
|
||
for (i = 0; i < count; i++) {
|
||
offset = i * 3;
|
||
data = {
|
||
type: userData[offset + 2] & 0x03,
|
||
pts: pts
|
||
};
|
||
|
||
// capture cc data when cc_valid is 1
|
||
if (userData[offset + 2] & 0x04) {
|
||
data.ccData = (userData[offset + 3] << 8) | userData[offset + 4];
|
||
results.push(data);
|
||
}
|
||
}
|
||
return results;
|
||
};
|
||
|
||
var CaptionStream = function() {
|
||
|
||
CaptionStream.prototype.init.call(this);
|
||
|
||
this.captionPackets_ = [];
|
||
|
||
this.ccStreams_ = [
|
||
new Cea608Stream(0, 0), // eslint-disable-line no-use-before-define
|
||
new Cea608Stream(0, 1), // eslint-disable-line no-use-before-define
|
||
new Cea608Stream(1, 0), // eslint-disable-line no-use-before-define
|
||
new Cea608Stream(1, 1) // eslint-disable-line no-use-before-define
|
||
];
|
||
|
||
this.reset();
|
||
|
||
// forward data and done events from CCs to this CaptionStream
|
||
this.ccStreams_.forEach(function(cc) {
|
||
cc.on('data', this.trigger.bind(this, 'data'));
|
||
cc.on('done', this.trigger.bind(this, 'done'));
|
||
}, this);
|
||
|
||
};
|
||
|
||
CaptionStream.prototype = new Stream();
|
||
CaptionStream.prototype.push = function(event) {
|
||
var sei, userData;
|
||
|
||
// only examine SEI NALs
|
||
if (event.nalUnitType !== 'sei_rbsp') {
|
||
return;
|
||
}
|
||
|
||
// parse the sei
|
||
sei = parseSei(event.escapedRBSP);
|
||
|
||
// ignore everything but user_data_registered_itu_t_t35
|
||
if (sei.payloadType !== USER_DATA_REGISTERED_ITU_T_T35) {
|
||
return;
|
||
}
|
||
|
||
// parse out the user data payload
|
||
userData = parseUserData(sei);
|
||
|
||
// ignore unrecognized userData
|
||
if (!userData) {
|
||
return;
|
||
}
|
||
|
||
// Sometimes, the same segment # will be downloaded twice. To stop the
|
||
// caption data from being processed twice, we track the latest dts we've
|
||
// received and ignore everything with a dts before that. However, since
|
||
// data for a specific dts can be split across 2 packets on either side of
|
||
// a segment boundary, we need to make sure we *don't* ignore the second
|
||
// dts packet we receive that has dts === this.latestDts_. And thus, the
|
||
// ignoreNextEqualDts_ flag was born.
|
||
if (event.dts < this.latestDts_) {
|
||
// We've started getting older data, so set the flag.
|
||
this.ignoreNextEqualDts_ = true;
|
||
return;
|
||
} else if ((event.dts === this.latestDts_) && (this.ignoreNextEqualDts_)) {
|
||
// We've received the last duplicate packet, time to start processing again
|
||
this.ignoreNextEqualDts_ = false;
|
||
return;
|
||
}
|
||
|
||
// parse out CC data packets and save them for later
|
||
this.captionPackets_ = this.captionPackets_.concat(parseCaptionPackets(event.pts, userData));
|
||
this.latestDts_ = event.dts;
|
||
};
|
||
|
||
CaptionStream.prototype.flush = function() {
|
||
// make sure we actually parsed captions before proceeding
|
||
if (!this.captionPackets_.length) {
|
||
this.ccStreams_.forEach(function(cc) {
|
||
cc.flush();
|
||
}, this);
|
||
return;
|
||
}
|
||
|
||
// In Chrome, the Array#sort function is not stable so add a
|
||
// presortIndex that we can use to ensure we get a stable-sort
|
||
this.captionPackets_.forEach(function(elem, idx) {
|
||
elem.presortIndex = idx;
|
||
});
|
||
|
||
// sort caption byte-pairs based on their PTS values
|
||
this.captionPackets_.sort(function(a, b) {
|
||
if (a.pts === b.pts) {
|
||
return a.presortIndex - b.presortIndex;
|
||
}
|
||
return a.pts - b.pts;
|
||
});
|
||
|
||
this.captionPackets_.forEach(function(packet) {
|
||
if (packet.type < 2) {
|
||
// Dispatch packet to the right Cea608Stream
|
||
this.dispatchCea608Packet(packet);
|
||
}
|
||
// this is where an 'else' would go for a dispatching packets
|
||
// to a theoretical Cea708Stream that handles SERVICEn data
|
||
}, this);
|
||
|
||
this.captionPackets_.length = 0;
|
||
this.ccStreams_.forEach(function(cc) {
|
||
cc.flush();
|
||
}, this);
|
||
return;
|
||
};
|
||
|
||
CaptionStream.prototype.reset = function() {
|
||
this.latestDts_ = null;
|
||
this.ignoreNextEqualDts_ = false;
|
||
this.activeCea608Channel_ = [null, null];
|
||
this.ccStreams_.forEach(function(ccStream) {
|
||
ccStream.reset();
|
||
});
|
||
};
|
||
|
||
CaptionStream.prototype.dispatchCea608Packet = function(packet) {
|
||
// NOTE: packet.type is the CEA608 field
|
||
if (this.setsChannel1Active(packet)) {
|
||
this.activeCea608Channel_[packet.type] = 0;
|
||
} else if (this.setsChannel2Active(packet)) {
|
||
this.activeCea608Channel_[packet.type] = 1;
|
||
}
|
||
if (this.activeCea608Channel_[packet.type] === null) {
|
||
// If we haven't received anything to set the active channel, discard the
|
||
// data; we don't want jumbled captions
|
||
return;
|
||
}
|
||
this.ccStreams_[(packet.type << 1) + this.activeCea608Channel_[packet.type]].push(packet);
|
||
};
|
||
|
||
CaptionStream.prototype.setsChannel1Active = function(packet) {
|
||
return ((packet.ccData & 0x7800) === 0x1000);
|
||
};
|
||
CaptionStream.prototype.setsChannel2Active = function(packet) {
|
||
return ((packet.ccData & 0x7800) === 0x1800);
|
||
};
|
||
|
||
// ----------------------
|
||
// Session to Application
|
||
// ----------------------
|
||
|
||
var CHARACTER_TRANSLATION = {
|
||
0x2a: 0xe1, // á
|
||
0x5c: 0xe9, // é
|
||
0x5e: 0xed, // í
|
||
0x5f: 0xf3, // ó
|
||
0x60: 0xfa, // ú
|
||
0x7b: 0xe7, // ç
|
||
0x7c: 0xf7, // ÷
|
||
0x7d: 0xd1, // Ñ
|
||
0x7e: 0xf1, // ñ
|
||
0x7f: 0x2588, // █
|
||
0x0130: 0xae, // ®
|
||
0x0131: 0xb0, // °
|
||
0x0132: 0xbd, // ½
|
||
0x0133: 0xbf, // ¿
|
||
0x0134: 0x2122, // ™
|
||
0x0135: 0xa2, // ¢
|
||
0x0136: 0xa3, // £
|
||
0x0137: 0x266a, // ♪
|
||
0x0138: 0xe0, // à
|
||
0x0139: 0xa0, //
|
||
0x013a: 0xe8, // è
|
||
0x013b: 0xe2, // â
|
||
0x013c: 0xea, // ê
|
||
0x013d: 0xee, // î
|
||
0x013e: 0xf4, // ô
|
||
0x013f: 0xfb, // û
|
||
0x0220: 0xc1, // Á
|
||
0x0221: 0xc9, // É
|
||
0x0222: 0xd3, // Ó
|
||
0x0223: 0xda, // Ú
|
||
0x0224: 0xdc, // Ü
|
||
0x0225: 0xfc, // ü
|
||
0x0226: 0x2018, // ‘
|
||
0x0227: 0xa1, // ¡
|
||
0x0228: 0x2a, // *
|
||
0x0229: 0x27, // '
|
||
0x022a: 0x2014, // —
|
||
0x022b: 0xa9, // ©
|
||
0x022c: 0x2120, // ℠
|
||
0x022d: 0x2022, // •
|
||
0x022e: 0x201c, // “
|
||
0x022f: 0x201d, // ”
|
||
0x0230: 0xc0, // À
|
||
0x0231: 0xc2, // Â
|
||
0x0232: 0xc7, // Ç
|
||
0x0233: 0xc8, // È
|
||
0x0234: 0xca, // Ê
|
||
0x0235: 0xcb, // Ë
|
||
0x0236: 0xeb, // ë
|
||
0x0237: 0xce, // Î
|
||
0x0238: 0xcf, // Ï
|
||
0x0239: 0xef, // ï
|
||
0x023a: 0xd4, // Ô
|
||
0x023b: 0xd9, // Ù
|
||
0x023c: 0xf9, // ù
|
||
0x023d: 0xdb, // Û
|
||
0x023e: 0xab, // «
|
||
0x023f: 0xbb, // »
|
||
0x0320: 0xc3, // Ã
|
||
0x0321: 0xe3, // ã
|
||
0x0322: 0xcd, // Í
|
||
0x0323: 0xcc, // Ì
|
||
0x0324: 0xec, // ì
|
||
0x0325: 0xd2, // Ò
|
||
0x0326: 0xf2, // ò
|
||
0x0327: 0xd5, // Õ
|
||
0x0328: 0xf5, // õ
|
||
0x0329: 0x7b, // {
|
||
0x032a: 0x7d, // }
|
||
0x032b: 0x5c, // \
|
||
0x032c: 0x5e, // ^
|
||
0x032d: 0x5f, // _
|
||
0x032e: 0x7c, // |
|
||
0x032f: 0x7e, // ~
|
||
0x0330: 0xc4, // Ä
|
||
0x0331: 0xe4, // ä
|
||
0x0332: 0xd6, // Ö
|
||
0x0333: 0xf6, // ö
|
||
0x0334: 0xdf, // ß
|
||
0x0335: 0xa5, // ¥
|
||
0x0336: 0xa4, // ¤
|
||
0x0337: 0x2502, // │
|
||
0x0338: 0xc5, // Å
|
||
0x0339: 0xe5, // å
|
||
0x033a: 0xd8, // Ø
|
||
0x033b: 0xf8, // ø
|
||
0x033c: 0x250c, // ┌
|
||
0x033d: 0x2510, // ┐
|
||
0x033e: 0x2514, // └
|
||
0x033f: 0x2518 // ┘
|
||
};
|
||
|
||
var getCharFromCode = function(code) {
|
||
if (code === null) {
|
||
return '';
|
||
}
|
||
code = CHARACTER_TRANSLATION[code] || code;
|
||
return String.fromCharCode(code);
|
||
};
|
||
|
||
// the index of the last row in a CEA-608 display buffer
|
||
var BOTTOM_ROW = 14;
|
||
|
||
// This array is used for mapping PACs -> row #, since there's no way of
|
||
// getting it through bit logic.
|
||
var ROWS = [0x1100, 0x1120, 0x1200, 0x1220, 0x1500, 0x1520, 0x1600, 0x1620,
|
||
0x1700, 0x1720, 0x1000, 0x1300, 0x1320, 0x1400, 0x1420];
|
||
|
||
// CEA-608 captions are rendered onto a 34x15 matrix of character
|
||
// cells. The "bottom" row is the last element in the outer array.
|
||
var createDisplayBuffer = function() {
|
||
var result = [], i = BOTTOM_ROW + 1;
|
||
while (i--) {
|
||
result.push('');
|
||
}
|
||
return result;
|
||
};
|
||
|
||
var Cea608Stream = function(field, dataChannel) {
|
||
Cea608Stream.prototype.init.call(this);
|
||
|
||
this.field_ = field || 0;
|
||
this.dataChannel_ = dataChannel || 0;
|
||
|
||
this.name_ = 'CC' + (((this.field_ << 1) | this.dataChannel_) + 1);
|
||
|
||
this.setConstants();
|
||
this.reset();
|
||
|
||
this.push = function(packet) {
|
||
var data, swap, char0, char1, text;
|
||
// remove the parity bits
|
||
data = packet.ccData & 0x7f7f;
|
||
|
||
// ignore duplicate control codes; the spec demands they're sent twice
|
||
if (data === this.lastControlCode_) {
|
||
this.lastControlCode_ = null;
|
||
return;
|
||
}
|
||
|
||
// Store control codes
|
||
if ((data & 0xf000) === 0x1000) {
|
||
this.lastControlCode_ = data;
|
||
} else if (data !== this.PADDING_) {
|
||
this.lastControlCode_ = null;
|
||
}
|
||
|
||
char0 = data >>> 8;
|
||
char1 = data & 0xff;
|
||
|
||
if (data === this.PADDING_) {
|
||
return;
|
||
|
||
} else if (data === this.RESUME_CAPTION_LOADING_) {
|
||
this.mode_ = 'popOn';
|
||
|
||
} else if (data === this.END_OF_CAPTION_) {
|
||
this.clearFormatting(packet.pts);
|
||
// if a caption was being displayed, it's gone now
|
||
this.flushDisplayed(packet.pts);
|
||
|
||
// flip memory
|
||
swap = this.displayed_;
|
||
this.displayed_ = this.nonDisplayed_;
|
||
this.nonDisplayed_ = swap;
|
||
|
||
// start measuring the time to display the caption
|
||
this.startPts_ = packet.pts;
|
||
|
||
} else if (data === this.ROLL_UP_2_ROWS_) {
|
||
this.topRow_ = BOTTOM_ROW - 1;
|
||
this.mode_ = 'rollUp';
|
||
} else if (data === this.ROLL_UP_3_ROWS_) {
|
||
this.topRow_ = BOTTOM_ROW - 2;
|
||
this.mode_ = 'rollUp';
|
||
} else if (data === this.ROLL_UP_4_ROWS_) {
|
||
this.topRow_ = BOTTOM_ROW - 3;
|
||
this.mode_ = 'rollUp';
|
||
} else if (data === this.CARRIAGE_RETURN_) {
|
||
this.clearFormatting(packet.pts);
|
||
this.flushDisplayed(packet.pts);
|
||
this.shiftRowsUp_();
|
||
this.startPts_ = packet.pts;
|
||
|
||
} else if (data === this.BACKSPACE_) {
|
||
if (this.mode_ === 'popOn') {
|
||
this.nonDisplayed_[BOTTOM_ROW] = this.nonDisplayed_[BOTTOM_ROW].slice(0, -1);
|
||
} else {
|
||
this.displayed_[BOTTOM_ROW] = this.displayed_[BOTTOM_ROW].slice(0, -1);
|
||
}
|
||
} else if (data === this.ERASE_DISPLAYED_MEMORY_) {
|
||
this.flushDisplayed(packet.pts);
|
||
this.displayed_ = createDisplayBuffer();
|
||
} else if (data === this.ERASE_NON_DISPLAYED_MEMORY_) {
|
||
this.nonDisplayed_ = createDisplayBuffer();
|
||
|
||
} else if (data === this.RESUME_DIRECT_CAPTIONING_) {
|
||
this.mode_ = 'paintOn';
|
||
|
||
// Append special characters to caption text
|
||
} else if (this.isSpecialCharacter(char0, char1)) {
|
||
// Bitmask char0 so that we can apply character transformations
|
||
// regardless of field and data channel.
|
||
// Then byte-shift to the left and OR with char1 so we can pass the
|
||
// entire character code to `getCharFromCode`.
|
||
char0 = (char0 & 0x03) << 8;
|
||
text = getCharFromCode(char0 | char1);
|
||
this[this.mode_](packet.pts, text);
|
||
this.column_++;
|
||
|
||
// Append extended characters to caption text
|
||
} else if (this.isExtCharacter(char0, char1)) {
|
||
// Extended characters always follow their "non-extended" equivalents.
|
||
// IE if a "è" is desired, you'll always receive "eè"; non-compliant
|
||
// decoders are supposed to drop the "è", while compliant decoders
|
||
// backspace the "e" and insert "è".
|
||
|
||
// Delete the previous character
|
||
if (this.mode_ === 'popOn') {
|
||
this.nonDisplayed_[this.row_] = this.nonDisplayed_[this.row_].slice(0, -1);
|
||
} else {
|
||
this.displayed_[BOTTOM_ROW] = this.displayed_[BOTTOM_ROW].slice(0, -1);
|
||
}
|
||
|
||
// Bitmask char0 so that we can apply character transformations
|
||
// regardless of field and data channel.
|
||
// Then byte-shift to the left and OR with char1 so we can pass the
|
||
// entire character code to `getCharFromCode`.
|
||
char0 = (char0 & 0x03) << 8;
|
||
text = getCharFromCode(char0 | char1);
|
||
this[this.mode_](packet.pts, text);
|
||
this.column_++;
|
||
|
||
// Process mid-row codes
|
||
} else if (this.isMidRowCode(char0, char1)) {
|
||
// Attributes are not additive, so clear all formatting
|
||
this.clearFormatting(packet.pts);
|
||
|
||
// According to the standard, mid-row codes
|
||
// should be replaced with spaces, so add one now
|
||
this[this.mode_](packet.pts, ' ');
|
||
this.column_++;
|
||
|
||
if ((char1 & 0xe) === 0xe) {
|
||
this.addFormatting(packet.pts, ['i']);
|
||
}
|
||
|
||
if ((char1 & 0x1) === 0x1) {
|
||
this.addFormatting(packet.pts, ['u']);
|
||
}
|
||
|
||
// Detect offset control codes and adjust cursor
|
||
} else if (this.isOffsetControlCode(char0, char1)) {
|
||
// Cursor position is set by indent PAC (see below) in 4-column
|
||
// increments, with an additional offset code of 1-3 to reach any
|
||
// of the 32 columns specified by CEA-608. So all we need to do
|
||
// here is increment the column cursor by the given offset.
|
||
this.column_ += (char1 & 0x03);
|
||
|
||
// Detect PACs (Preamble Address Codes)
|
||
} else if (this.isPAC(char0, char1)) {
|
||
|
||
// There's no logic for PAC -> row mapping, so we have to just
|
||
// find the row code in an array and use its index :(
|
||
var row = ROWS.indexOf(data & 0x1f20);
|
||
|
||
if (row !== this.row_) {
|
||
// formatting is only persistent for current row
|
||
this.clearFormatting(packet.pts);
|
||
this.row_ = row;
|
||
}
|
||
// All PACs can apply underline, so detect and apply
|
||
// (All odd-numbered second bytes set underline)
|
||
if ((char1 & 0x1) && (this.formatting_.indexOf('u') === -1)) {
|
||
this.addFormatting(packet.pts, ['u']);
|
||
}
|
||
|
||
if ((data & 0x10) === 0x10) {
|
||
// We've got an indent level code. Each successive even number
|
||
// increments the column cursor by 4, so we can get the desired
|
||
// column position by bit-shifting to the right (to get n/2)
|
||
// and multiplying by 4.
|
||
this.column_ = ((data & 0xe) >> 1) * 4;
|
||
}
|
||
|
||
if (this.isColorPAC(char1)) {
|
||
// it's a color code, though we only support white, which
|
||
// can be either normal or italicized. white italics can be
|
||
// either 0x4e or 0x6e depending on the row, so we just
|
||
// bitwise-and with 0xe to see if italics should be turned on
|
||
if ((char1 & 0xe) === 0xe) {
|
||
this.addFormatting(packet.pts, ['i']);
|
||
}
|
||
}
|
||
|
||
// We have a normal character in char0, and possibly one in char1
|
||
} else if (this.isNormalChar(char0)) {
|
||
if (char1 === 0x00) {
|
||
char1 = null;
|
||
}
|
||
text = getCharFromCode(char0);
|
||
text += getCharFromCode(char1);
|
||
this[this.mode_](packet.pts, text);
|
||
this.column_ += text.length;
|
||
|
||
} // finish data processing
|
||
|
||
};
|
||
};
|
||
Cea608Stream.prototype = new Stream();
|
||
// Trigger a cue point that captures the current state of the
|
||
// display buffer
|
||
Cea608Stream.prototype.flushDisplayed = function(pts) {
|
||
var content = this.displayed_
|
||
// remove spaces from the start and end of the string
|
||
.map(function(row) {
|
||
return row.trim();
|
||
})
|
||
// combine all text rows to display in one cue
|
||
.join('\n')
|
||
// and remove blank rows from the start and end, but not the middle
|
||
.replace(/^\n+|\n+$/g, '');
|
||
|
||
if (content.length) {
|
||
this.trigger('data', {
|
||
startPts: this.startPts_,
|
||
endPts: pts,
|
||
text: content,
|
||
stream: this.name_
|
||
});
|
||
}
|
||
};
|
||
|
||
/**
|
||
* Zero out the data, used for startup and on seek
|
||
*/
|
||
Cea608Stream.prototype.reset = function() {
|
||
this.mode_ = 'popOn';
|
||
// When in roll-up mode, the index of the last row that will
|
||
// actually display captions. If a caption is shifted to a row
|
||
// with a lower index than this, it is cleared from the display
|
||
// buffer
|
||
this.topRow_ = 0;
|
||
this.startPts_ = 0;
|
||
this.displayed_ = createDisplayBuffer();
|
||
this.nonDisplayed_ = createDisplayBuffer();
|
||
this.lastControlCode_ = null;
|
||
|
||
// Track row and column for proper line-breaking and spacing
|
||
this.column_ = 0;
|
||
this.row_ = BOTTOM_ROW;
|
||
|
||
// This variable holds currently-applied formatting
|
||
this.formatting_ = [];
|
||
};
|
||
|
||
/**
|
||
* Sets up control code and related constants for this instance
|
||
*/
|
||
Cea608Stream.prototype.setConstants = function() {
|
||
// The following attributes have these uses:
|
||
// ext_ : char0 for mid-row codes, and the base for extended
|
||
// chars (ext_+0, ext_+1, and ext_+2 are char0s for
|
||
// extended codes)
|
||
// control_: char0 for control codes, except byte-shifted to the
|
||
// left so that we can do this.control_ | CONTROL_CODE
|
||
// offset_: char0 for tab offset codes
|
||
//
|
||
// It's also worth noting that control codes, and _only_ control codes,
|
||
// differ between field 1 and field2. Field 2 control codes are always
|
||
// their field 1 value plus 1. That's why there's the "| field" on the
|
||
// control value.
|
||
if (this.dataChannel_ === 0) {
|
||
this.BASE_ = 0x10;
|
||
this.EXT_ = 0x11;
|
||
this.CONTROL_ = (0x14 | this.field_) << 8;
|
||
this.OFFSET_ = 0x17;
|
||
} else if (this.dataChannel_ === 1) {
|
||
this.BASE_ = 0x18;
|
||
this.EXT_ = 0x19;
|
||
this.CONTROL_ = (0x1c | this.field_) << 8;
|
||
this.OFFSET_ = 0x1f;
|
||
}
|
||
|
||
// Constants for the LSByte command codes recognized by Cea608Stream. This
|
||
// list is not exhaustive. For a more comprehensive listing and semantics see
|
||
// http://www.gpo.gov/fdsys/pkg/CFR-2010-title47-vol1/pdf/CFR-2010-title47-vol1-sec15-119.pdf
|
||
// Padding
|
||
this.PADDING_ = 0x0000;
|
||
// Pop-on Mode
|
||
this.RESUME_CAPTION_LOADING_ = this.CONTROL_ | 0x20;
|
||
this.END_OF_CAPTION_ = this.CONTROL_ | 0x2f;
|
||
// Roll-up Mode
|
||
this.ROLL_UP_2_ROWS_ = this.CONTROL_ | 0x25;
|
||
this.ROLL_UP_3_ROWS_ = this.CONTROL_ | 0x26;
|
||
this.ROLL_UP_4_ROWS_ = this.CONTROL_ | 0x27;
|
||
this.CARRIAGE_RETURN_ = this.CONTROL_ | 0x2d;
|
||
// paint-on mode (not supported)
|
||
this.RESUME_DIRECT_CAPTIONING_ = this.CONTROL_ | 0x29;
|
||
// Erasure
|
||
this.BACKSPACE_ = this.CONTROL_ | 0x21;
|
||
this.ERASE_DISPLAYED_MEMORY_ = this.CONTROL_ | 0x2c;
|
||
this.ERASE_NON_DISPLAYED_MEMORY_ = this.CONTROL_ | 0x2e;
|
||
};
|
||
|
||
/**
|
||
* Detects if the 2-byte packet data is a special character
|
||
*
|
||
* Special characters have a second byte in the range 0x30 to 0x3f,
|
||
* with the first byte being 0x11 (for data channel 1) or 0x19 (for
|
||
* data channel 2).
|
||
*
|
||
* @param {Integer} char0 The first byte
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the 2 bytes are an special character
|
||
*/
|
||
Cea608Stream.prototype.isSpecialCharacter = function(char0, char1) {
|
||
return (char0 === this.EXT_ && char1 >= 0x30 && char1 <= 0x3f);
|
||
};
|
||
|
||
/**
|
||
* Detects if the 2-byte packet data is an extended character
|
||
*
|
||
* Extended characters have a second byte in the range 0x20 to 0x3f,
|
||
* with the first byte being 0x12 or 0x13 (for data channel 1) or
|
||
* 0x1a or 0x1b (for data channel 2).
|
||
*
|
||
* @param {Integer} char0 The first byte
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the 2 bytes are an extended character
|
||
*/
|
||
Cea608Stream.prototype.isExtCharacter = function(char0, char1) {
|
||
return ((char0 === (this.EXT_ + 1) || char0 === (this.EXT_ + 2)) &&
|
||
(char1 >= 0x20 && char1 <= 0x3f));
|
||
};
|
||
|
||
/**
|
||
* Detects if the 2-byte packet is a mid-row code
|
||
*
|
||
* Mid-row codes have a second byte in the range 0x20 to 0x2f, with
|
||
* the first byte being 0x11 (for data channel 1) or 0x19 (for data
|
||
* channel 2).
|
||
*
|
||
* @param {Integer} char0 The first byte
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the 2 bytes are a mid-row code
|
||
*/
|
||
Cea608Stream.prototype.isMidRowCode = function(char0, char1) {
|
||
return (char0 === this.EXT_ && (char1 >= 0x20 && char1 <= 0x2f));
|
||
};
|
||
|
||
/**
|
||
* Detects if the 2-byte packet is an offset control code
|
||
*
|
||
* Offset control codes have a second byte in the range 0x21 to 0x23,
|
||
* with the first byte being 0x17 (for data channel 1) or 0x1f (for
|
||
* data channel 2).
|
||
*
|
||
* @param {Integer} char0 The first byte
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the 2 bytes are an offset control code
|
||
*/
|
||
Cea608Stream.prototype.isOffsetControlCode = function(char0, char1) {
|
||
return (char0 === this.OFFSET_ && (char1 >= 0x21 && char1 <= 0x23));
|
||
};
|
||
|
||
/**
|
||
* Detects if the 2-byte packet is a Preamble Address Code
|
||
*
|
||
* PACs have a first byte in the range 0x10 to 0x17 (for data channel 1)
|
||
* or 0x18 to 0x1f (for data channel 2), with the second byte in the
|
||
* range 0x40 to 0x7f.
|
||
*
|
||
* @param {Integer} char0 The first byte
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the 2 bytes are a PAC
|
||
*/
|
||
Cea608Stream.prototype.isPAC = function(char0, char1) {
|
||
return (char0 >= this.BASE_ && char0 < (this.BASE_ + 8) &&
|
||
(char1 >= 0x40 && char1 <= 0x7f));
|
||
};
|
||
|
||
/**
|
||
* Detects if a packet's second byte is in the range of a PAC color code
|
||
*
|
||
* PAC color codes have the second byte be in the range 0x40 to 0x4f, or
|
||
* 0x60 to 0x6f.
|
||
*
|
||
* @param {Integer} char1 The second byte
|
||
* @return {Boolean} Whether the byte is a color PAC
|
||
*/
|
||
Cea608Stream.prototype.isColorPAC = function(char1) {
|
||
return ((char1 >= 0x40 && char1 <= 0x4f) || (char1 >= 0x60 && char1 <= 0x7f));
|
||
};
|
||
|
||
/**
|
||
* Detects if a single byte is in the range of a normal character
|
||
*
|
||
* Normal text bytes are in the range 0x20 to 0x7f.
|
||
*
|
||
* @param {Integer} char The byte
|
||
* @return {Boolean} Whether the byte is a normal character
|
||
*/
|
||
Cea608Stream.prototype.isNormalChar = function(char) {
|
||
return (char >= 0x20 && char <= 0x7f);
|
||
};
|
||
|
||
// Adds the opening HTML tag for the passed character to the caption text,
|
||
// and keeps track of it for later closing
|
||
Cea608Stream.prototype.addFormatting = function(pts, format) {
|
||
this.formatting_ = this.formatting_.concat(format);
|
||
var text = format.reduce(function(text, format) {
|
||
return text + '<' + format + '>';
|
||
}, '');
|
||
this[this.mode_](pts, text);
|
||
};
|
||
|
||
// Adds HTML closing tags for current formatting to caption text and
|
||
// clears remembered formatting
|
||
Cea608Stream.prototype.clearFormatting = function(pts) {
|
||
if (!this.formatting_.length) {
|
||
return;
|
||
}
|
||
var text = this.formatting_.reverse().reduce(function(text, format) {
|
||
return text + '</' + format + '>';
|
||
}, '');
|
||
this.formatting_ = [];
|
||
this[this.mode_](pts, text);
|
||
};
|
||
|
||
// Mode Implementations
|
||
Cea608Stream.prototype.popOn = function(pts, text) {
|
||
var baseRow = this.nonDisplayed_[this.row_];
|
||
|
||
// buffer characters
|
||
baseRow += text;
|
||
this.nonDisplayed_[this.row_] = baseRow;
|
||
};
|
||
|
||
Cea608Stream.prototype.rollUp = function(pts, text) {
|
||
var baseRow = this.displayed_[BOTTOM_ROW];
|
||
|
||
baseRow += text;
|
||
this.displayed_[BOTTOM_ROW] = baseRow;
|
||
|
||
};
|
||
|
||
Cea608Stream.prototype.shiftRowsUp_ = function() {
|
||
var i;
|
||
// clear out inactive rows
|
||
for (i = 0; i < this.topRow_; i++) {
|
||
this.displayed_[i] = '';
|
||
}
|
||
// shift displayed rows up
|
||
for (i = this.topRow_; i < BOTTOM_ROW; i++) {
|
||
this.displayed_[i] = this.displayed_[i + 1];
|
||
}
|
||
// clear out the bottom row
|
||
this.displayed_[BOTTOM_ROW] = '';
|
||
};
|
||
|
||
// paintOn mode is not implemented
|
||
Cea608Stream.prototype.paintOn = function() {};
|
||
|
||
// exports
|
||
module.exports = {
|
||
CaptionStream: CaptionStream,
|
||
Cea608Stream: Cea608Stream
|
||
};
|
||
|
||
},{"../utils/stream":15}],10:[function(require,module,exports){
|
||
/**
|
||
* mux.js
|
||
*
|
||
* Copyright (c) 2015 Brightcove
|
||
* All rights reserved.
|
||
*
|
||
* A stream-based mp2t to mp4 converter. This utility can be used to
|
||
* deliver mp4s to a SourceBuffer on platforms that support native
|
||
* Media Source Extensions.
|
||
*/
|
||
'use strict';
|
||
var Stream = require('../utils/stream.js'),
|
||
CaptionStream = require('./caption-stream'),
|
||
StreamTypes = require('./stream-types'),
|
||
TimestampRolloverStream = require('./timestamp-rollover-stream').TimestampRolloverStream;
|
||
|
||
var m2tsStreamTypes = require('./stream-types.js');
|
||
|
||
// object types
|
||
var TransportPacketStream, TransportParseStream, ElementaryStream;
|
||
|
||
// constants
|
||
var
|
||
MP2T_PACKET_LENGTH = 188, // bytes
|
||
SYNC_BYTE = 0x47;
|
||
|
||
/**
|
||
* Splits an incoming stream of binary data into MPEG-2 Transport
|
||
* Stream packets.
|
||
*/
|
||
TransportPacketStream = function() {
|
||
var
|
||
buffer = new Uint8Array(MP2T_PACKET_LENGTH),
|
||
bytesInBuffer = 0;
|
||
|
||
TransportPacketStream.prototype.init.call(this);
|
||
|
||
// Deliver new bytes to the stream.
|
||
|
||
this.push = function(bytes) {
|
||
var
|
||
startIndex = 0,
|
||
endIndex = MP2T_PACKET_LENGTH,
|
||
everything;
|
||
|
||
// If there are bytes remaining from the last segment, prepend them to the
|
||
// bytes that were pushed in
|
||
if (bytesInBuffer) {
|
||
everything = new Uint8Array(bytes.byteLength + bytesInBuffer);
|
||
everything.set(buffer.subarray(0, bytesInBuffer));
|
||
everything.set(bytes, bytesInBuffer);
|
||
bytesInBuffer = 0;
|
||
} else {
|
||
everything = bytes;
|
||
}
|
||
|
||
// While we have enough data for a packet
|
||
while (endIndex < everything.byteLength) {
|
||
// Look for a pair of start and end sync bytes in the data..
|
||
if (everything[startIndex] === SYNC_BYTE && everything[endIndex] === SYNC_BYTE) {
|
||
// We found a packet so emit it and jump one whole packet forward in
|
||
// the stream
|
||
this.trigger('data', everything.subarray(startIndex, endIndex));
|
||
startIndex += MP2T_PACKET_LENGTH;
|
||
endIndex += MP2T_PACKET_LENGTH;
|
||
continue;
|
||
}
|
||
// If we get here, we have somehow become de-synchronized and we need to step
|
||
// forward one byte at a time until we find a pair of sync bytes that denote
|
||
// a packet
|
||
startIndex++;
|
||
endIndex++;
|
||
}
|
||
|
||
// If there was some data left over at the end of the segment that couldn't
|
||
// possibly be a whole packet, keep it because it might be the start of a packet
|
||
// that continues in the next segment
|
||
if (startIndex < everything.byteLength) {
|
||
buffer.set(everything.subarray(startIndex), 0);
|
||
bytesInBuffer = everything.byteLength - startIndex;
|
||
}
|
||
};
|
||
|
||
this.flush = function() {
|
||
// If the buffer contains a whole packet when we are being flushed, emit it
|
||
// and empty the buffer. Otherwise hold onto the data because it may be
|
||
// important for decoding the next segment
|
||
if (bytesInBuffer === MP2T_PACKET_LENGTH && buffer[0] === SYNC_BYTE) {
|
||
this.trigger('data', buffer);
|
||
bytesInBuffer = 0;
|
||
}
|
||
this.trigger('done');
|
||
};
|
||
};
|
||
TransportPacketStream.prototype = new Stream();
|
||
|
||
/**
|
||
* Accepts an MP2T TransportPacketStream and emits data events with parsed
|
||
* forms of the individual transport stream packets.
|
||
*/
|
||
TransportParseStream = function() {
|
||
var parsePsi, parsePat, parsePmt, self;
|
||
TransportParseStream.prototype.init.call(this);
|
||
self = this;
|
||
|
||
this.packetsWaitingForPmt = [];
|
||
this.programMapTable = undefined;
|
||
|
||
parsePsi = function(payload, psi) {
|
||
var offset = 0;
|
||
|
||
// PSI packets may be split into multiple sections and those
|
||
// sections may be split into multiple packets. If a PSI
|
||
// section starts in this packet, the payload_unit_start_indicator
|
||
// will be true and the first byte of the payload will indicate
|
||
// the offset from the current position to the start of the
|
||
// section.
|
||
if (psi.payloadUnitStartIndicator) {
|
||
offset += payload[offset] + 1;
|
||
}
|
||
|
||
if (psi.type === 'pat') {
|
||
parsePat(payload.subarray(offset), psi);
|
||
} else {
|
||
parsePmt(payload.subarray(offset), psi);
|
||
}
|
||
};
|
||
|
||
parsePat = function(payload, pat) {
|
||
pat.section_number = payload[7]; // eslint-disable-line camelcase
|
||
pat.last_section_number = payload[8]; // eslint-disable-line camelcase
|
||
|
||
// skip the PSI header and parse the first PMT entry
|
||
self.pmtPid = (payload[10] & 0x1F) << 8 | payload[11];
|
||
pat.pmtPid = self.pmtPid;
|
||
};
|
||
|
||
/**
|
||
* Parse out the relevant fields of a Program Map Table (PMT).
|
||
* @param payload {Uint8Array} the PMT-specific portion of an MP2T
|
||
* packet. The first byte in this array should be the table_id
|
||
* field.
|
||
* @param pmt {object} the object that should be decorated with
|
||
* fields parsed from the PMT.
|
||
*/
|
||
parsePmt = function(payload, pmt) {
|
||
var sectionLength, tableEnd, programInfoLength, offset;
|
||
|
||
// PMTs can be sent ahead of the time when they should actually
|
||
// take effect. We don't believe this should ever be the case
|
||
// for HLS but we'll ignore "forward" PMT declarations if we see
|
||
// them. Future PMT declarations have the current_next_indicator
|
||
// set to zero.
|
||
if (!(payload[5] & 0x01)) {
|
||
return;
|
||
}
|
||
|
||
// overwrite any existing program map table
|
||
self.programMapTable = {
|
||
video: null,
|
||
audio: null,
|
||
'timed-metadata': {}
|
||
};
|
||
|
||
// the mapping table ends at the end of the current section
|
||
sectionLength = (payload[1] & 0x0f) << 8 | payload[2];
|
||
tableEnd = 3 + sectionLength - 4;
|
||
|
||
// to determine where the table is, we have to figure out how
|
||
// long the program info descriptors are
|
||
programInfoLength = (payload[10] & 0x0f) << 8 | payload[11];
|
||
|
||
// advance the offset to the first entry in the mapping table
|
||
offset = 12 + programInfoLength;
|
||
while (offset < tableEnd) {
|
||
var streamType = payload[offset];
|
||
var pid = (payload[offset + 1] & 0x1F) << 8 | payload[offset + 2];
|
||
|
||
// only map a single elementary_pid for audio and video stream types
|
||
// TODO: should this be done for metadata too? for now maintain behavior of
|
||
// multiple metadata streams
|
||
if (streamType === StreamTypes.H264_STREAM_TYPE &&
|
||
self.programMapTable.video === null) {
|
||
self.programMapTable.video = pid;
|
||
} else if (streamType === StreamTypes.ADTS_STREAM_TYPE &&
|
||
self.programMapTable.audio === null) {
|
||
self.programMapTable.audio = pid;
|
||
} else if (streamType === StreamTypes.METADATA_STREAM_TYPE) {
|
||
// map pid to stream type for metadata streams
|
||
self.programMapTable['timed-metadata'][pid] = streamType;
|
||
}
|
||
|
||
// move to the next table entry
|
||
// skip past the elementary stream descriptors, if present
|
||
offset += ((payload[offset + 3] & 0x0F) << 8 | payload[offset + 4]) + 5;
|
||
}
|
||
|
||
// record the map on the packet as well
|
||
pmt.programMapTable = self.programMapTable;
|
||
};
|
||
|
||
/**
|
||
* Deliver a new MP2T packet to the stream.
|
||
*/
|
||
this.push = function(packet) {
|
||
var
|
||
result = {},
|
||
offset = 4;
|
||
|
||
result.payloadUnitStartIndicator = !!(packet[1] & 0x40);
|
||
|
||
// pid is a 13-bit field starting at the last bit of packet[1]
|
||
result.pid = packet[1] & 0x1f;
|
||
result.pid <<= 8;
|
||
result.pid |= packet[2];
|
||
|
||
// if an adaption field is present, its length is specified by the
|
||
// fifth byte of the TS packet header. The adaptation field is
|
||
// used to add stuffing to PES packets that don't fill a complete
|
||
// TS packet, and to specify some forms of timing and control data
|
||
// that we do not currently use.
|
||
if (((packet[3] & 0x30) >>> 4) > 0x01) {
|
||
offset += packet[offset] + 1;
|
||
}
|
||
|
||
// parse the rest of the packet based on the type
|
||
if (result.pid === 0) {
|
||
result.type = 'pat';
|
||
parsePsi(packet.subarray(offset), result);
|
||
this.trigger('data', result);
|
||
} else if (result.pid === this.pmtPid) {
|
||
result.type = 'pmt';
|
||
parsePsi(packet.subarray(offset), result);
|
||
this.trigger('data', result);
|
||
|
||
// if there are any packets waiting for a PMT to be found, process them now
|
||
while (this.packetsWaitingForPmt.length) {
|
||
this.processPes_.apply(this, this.packetsWaitingForPmt.shift());
|
||
}
|
||
} else if (this.programMapTable === undefined) {
|
||
// When we have not seen a PMT yet, defer further processing of
|
||
// PES packets until one has been parsed
|
||
this.packetsWaitingForPmt.push([packet, offset, result]);
|
||
} else {
|
||
this.processPes_(packet, offset, result);
|
||
}
|
||
};
|
||
|
||
this.processPes_ = function(packet, offset, result) {
|
||
// set the appropriate stream type
|
||
if (result.pid === this.programMapTable.video) {
|
||
result.streamType = StreamTypes.H264_STREAM_TYPE;
|
||
} else if (result.pid === this.programMapTable.audio) {
|
||
result.streamType = StreamTypes.ADTS_STREAM_TYPE;
|
||
} else {
|
||
// if not video or audio, it is timed-metadata or unknown
|
||
// if unknown, streamType will be undefined
|
||
result.streamType = this.programMapTable['timed-metadata'][result.pid];
|
||
}
|
||
|
||
result.type = 'pes';
|
||
result.data = packet.subarray(offset);
|
||
|
||
this.trigger('data', result);
|
||
};
|
||
|
||
};
|
||
TransportParseStream.prototype = new Stream();
|
||
TransportParseStream.STREAM_TYPES = {
|
||
h264: 0x1b,
|
||
adts: 0x0f
|
||
};
|
||
|
||
/**
|
||
* Reconsistutes program elementary stream (PES) packets from parsed
|
||
* transport stream packets. That is, if you pipe an
|
||
* mp2t.TransportParseStream into a mp2t.ElementaryStream, the output
|
||
* events will be events which capture the bytes for individual PES
|
||
* packets plus relevant metadata that has been extracted from the
|
||
* container.
|
||
*/
|
||
ElementaryStream = function() {
|
||
var
|
||
self = this,
|
||
// PES packet fragments
|
||
video = {
|
||
data: [],
|
||
size: 0
|
||
},
|
||
audio = {
|
||
data: [],
|
||
size: 0
|
||
},
|
||
timedMetadata = {
|
||
data: [],
|
||
size: 0
|
||
},
|
||
parsePes = function(payload, pes) {
|
||
var ptsDtsFlags;
|
||
|
||
// get the packet length, this will be 0 for video
|
||
pes.packetLength = 6 + ((payload[4] << 8) | payload[5]);
|
||
|
||
// find out if this packets starts a new keyframe
|
||
pes.dataAlignmentIndicator = (payload[6] & 0x04) !== 0;
|
||
// PES packets may be annotated with a PTS value, or a PTS value
|
||
// and a DTS value. Determine what combination of values is
|
||
// available to work with.
|
||
ptsDtsFlags = payload[7];
|
||
|
||
// PTS and DTS are normally stored as a 33-bit number. Javascript
|
||
// performs all bitwise operations on 32-bit integers but javascript
|
||
// supports a much greater range (52-bits) of integer using standard
|
||
// mathematical operations.
|
||
// We construct a 31-bit value using bitwise operators over the 31
|
||
// most significant bits and then multiply by 4 (equal to a left-shift
|
||
// of 2) before we add the final 2 least significant bits of the
|
||
// timestamp (equal to an OR.)
|
||
if (ptsDtsFlags & 0xC0) {
|
||
// the PTS and DTS are not written out directly. For information
|
||
// on how they are encoded, see
|
||
// http://dvd.sourceforge.net/dvdinfo/pes-hdr.html
|
||
pes.pts = (payload[9] & 0x0E) << 27 |
|
||
(payload[10] & 0xFF) << 20 |
|
||
(payload[11] & 0xFE) << 12 |
|
||
(payload[12] & 0xFF) << 5 |
|
||
(payload[13] & 0xFE) >>> 3;
|
||
pes.pts *= 4; // Left shift by 2
|
||
pes.pts += (payload[13] & 0x06) >>> 1; // OR by the two LSBs
|
||
pes.dts = pes.pts;
|
||
if (ptsDtsFlags & 0x40) {
|
||
pes.dts = (payload[14] & 0x0E) << 27 |
|
||
(payload[15] & 0xFF) << 20 |
|
||
(payload[16] & 0xFE) << 12 |
|
||
(payload[17] & 0xFF) << 5 |
|
||
(payload[18] & 0xFE) >>> 3;
|
||
pes.dts *= 4; // Left shift by 2
|
||
pes.dts += (payload[18] & 0x06) >>> 1; // OR by the two LSBs
|
||
}
|
||
}
|
||
// the data section starts immediately after the PES header.
|
||
// pes_header_data_length specifies the number of header bytes
|
||
// that follow the last byte of the field.
|
||
pes.data = payload.subarray(9 + payload[8]);
|
||
},
|
||
flushStream = function(stream, type, forceFlush) {
|
||
var
|
||
packetData = new Uint8Array(stream.size),
|
||
event = {
|
||
type: type
|
||
},
|
||
i = 0,
|
||
offset = 0,
|
||
packetFlushable = false,
|
||
fragment;
|
||
|
||
// do nothing if there is not enough buffered data for a complete
|
||
// PES header
|
||
if (!stream.data.length || stream.size < 9) {
|
||
return;
|
||
}
|
||
event.trackId = stream.data[0].pid;
|
||
|
||
// reassemble the packet
|
||
for (i = 0; i < stream.data.length; i++) {
|
||
fragment = stream.data[i];
|
||
|
||
packetData.set(fragment.data, offset);
|
||
offset += fragment.data.byteLength;
|
||
}
|
||
|
||
// parse assembled packet's PES header
|
||
parsePes(packetData, event);
|
||
|
||
// non-video PES packets MUST have a non-zero PES_packet_length
|
||
// check that there is enough stream data to fill the packet
|
||
packetFlushable = type === 'video' || event.packetLength <= stream.size;
|
||
|
||
// flush pending packets if the conditions are right
|
||
if (forceFlush || packetFlushable) {
|
||
stream.size = 0;
|
||
stream.data.length = 0;
|
||
}
|
||
|
||
// only emit packets that are complete. this is to avoid assembling
|
||
// incomplete PES packets due to poor segmentation
|
||
if (packetFlushable) {
|
||
self.trigger('data', event);
|
||
}
|
||
};
|
||
|
||
ElementaryStream.prototype.init.call(this);
|
||
|
||
this.push = function(data) {
|
||
({
|
||
pat: function() {
|
||
// we have to wait for the PMT to arrive as well before we
|
||
// have any meaningful metadata
|
||
},
|
||
pes: function() {
|
||
var stream, streamType;
|
||
|
||
switch (data.streamType) {
|
||
case StreamTypes.H264_STREAM_TYPE:
|
||
case m2tsStreamTypes.H264_STREAM_TYPE:
|
||
stream = video;
|
||
streamType = 'video';
|
||
break;
|
||
case StreamTypes.ADTS_STREAM_TYPE:
|
||
stream = audio;
|
||
streamType = 'audio';
|
||
break;
|
||
case StreamTypes.METADATA_STREAM_TYPE:
|
||
stream = timedMetadata;
|
||
streamType = 'timed-metadata';
|
||
break;
|
||
default:
|
||
// ignore unknown stream types
|
||
return;
|
||
}
|
||
|
||
// if a new packet is starting, we can flush the completed
|
||
// packet
|
||
if (data.payloadUnitStartIndicator) {
|
||
flushStream(stream, streamType, true);
|
||
}
|
||
|
||
// buffer this fragment until we are sure we've received the
|
||
// complete payload
|
||
stream.data.push(data);
|
||
stream.size += data.data.byteLength;
|
||
},
|
||
pmt: function() {
|
||
var
|
||
event = {
|
||
type: 'metadata',
|
||
tracks: []
|
||
},
|
||
programMapTable = data.programMapTable;
|
||
|
||
// translate audio and video streams to tracks
|
||
if (programMapTable.video !== null) {
|
||
event.tracks.push({
|
||
timelineStartInfo: {
|
||
baseMediaDecodeTime: 0
|
||
},
|
||
id: +programMapTable.video,
|
||
codec: 'avc',
|
||
type: 'video'
|
||
});
|
||
}
|
||
if (programMapTable.audio !== null) {
|
||
event.tracks.push({
|
||
timelineStartInfo: {
|
||
baseMediaDecodeTime: 0
|
||
},
|
||
id: +programMapTable.audio,
|
||
codec: 'adts',
|
||
type: 'audio'
|
||
});
|
||
}
|
||
|
||
self.trigger('data', event);
|
||
}
|
||
})[data.type]();
|
||
};
|
||
|
||
/**
|
||
* Flush any remaining input. Video PES packets may be of variable
|
||
* length. Normally, the start of a new video packet can trigger the
|
||
* finalization of the previous packet. That is not possible if no
|
||
* more video is forthcoming, however. In that case, some other
|
||
* mechanism (like the end of the file) has to be employed. When it is
|
||
* clear that no additional data is forthcoming, calling this method
|
||
* will flush the buffered packets.
|
||
*/
|
||
this.flush = function() {
|
||
// !!THIS ORDER IS IMPORTANT!!
|
||
// video first then audio
|
||
flushStream(video, 'video');
|
||
flushStream(audio, 'audio');
|
||
flushStream(timedMetadata, 'timed-metadata');
|
||
this.trigger('done');
|
||
};
|
||
};
|
||
ElementaryStream.prototype = new Stream();
|
||
|
||
var m2ts = {
|
||
PAT_PID: 0x0000,
|
||
MP2T_PACKET_LENGTH: MP2T_PACKET_LENGTH,
|
||
TransportPacketStream: TransportPacketStream,
|
||
TransportParseStream: TransportParseStream,
|
||
ElementaryStream: ElementaryStream,
|
||
TimestampRolloverStream: TimestampRolloverStream,
|
||
CaptionStream: CaptionStream.CaptionStream,
|
||
Cea608Stream: CaptionStream.Cea608Stream,
|
||
MetadataStream: require('./metadata-stream')
|
||
};
|
||
|
||
for (var type in StreamTypes) {
|
||
if (StreamTypes.hasOwnProperty(type)) {
|
||
m2ts[type] = StreamTypes[type];
|
||
}
|
||
}
|
||
|
||
module.exports = m2ts;
|
||
|
||
},{"../utils/stream.js":15,"./caption-stream":9,"./metadata-stream":11,"./stream-types":12,"./stream-types.js":12,"./timestamp-rollover-stream":13}],11:[function(require,module,exports){
|
||
/**
|
||
* Accepts program elementary stream (PES) data events and parses out
|
||
* ID3 metadata from them, if present.
|
||
* @see http://id3.org/id3v2.3.0
|
||
*/
|
||
'use strict';
|
||
var
|
||
Stream = require('../utils/stream'),
|
||
StreamTypes = require('./stream-types'),
|
||
// return a percent-encoded representation of the specified byte range
|
||
// @see http://en.wikipedia.org/wiki/Percent-encoding
|
||
percentEncode = function(bytes, start, end) {
|
||
var i, result = '';
|
||
for (i = start; i < end; i++) {
|
||
result += '%' + ('00' + bytes[i].toString(16)).slice(-2);
|
||
}
|
||
return result;
|
||
},
|
||
// return the string representation of the specified byte range,
|
||
// interpreted as UTf-8.
|
||
parseUtf8 = function(bytes, start, end) {
|
||
return decodeURIComponent(percentEncode(bytes, start, end));
|
||
},
|
||
// return the string representation of the specified byte range,
|
||
// interpreted as ISO-8859-1.
|
||
parseIso88591 = function(bytes, start, end) {
|
||
return unescape(percentEncode(bytes, start, end)); // jshint ignore:line
|
||
},
|
||
parseSyncSafeInteger = function(data) {
|
||
return (data[0] << 21) |
|
||
(data[1] << 14) |
|
||
(data[2] << 7) |
|
||
(data[3]);
|
||
},
|
||
tagParsers = {
|
||
TXXX: function(tag) {
|
||
var i;
|
||
if (tag.data[0] !== 3) {
|
||
// ignore frames with unrecognized character encodings
|
||
return;
|
||
}
|
||
|
||
for (i = 1; i < tag.data.length; i++) {
|
||
if (tag.data[i] === 0) {
|
||
// parse the text fields
|
||
tag.description = parseUtf8(tag.data, 1, i);
|
||
// do not include the null terminator in the tag value
|
||
tag.value = parseUtf8(tag.data, i + 1, tag.data.length).replace(/\0*$/, '');
|
||
break;
|
||
}
|
||
}
|
||
tag.data = tag.value;
|
||
},
|
||
WXXX: function(tag) {
|
||
var i;
|
||
if (tag.data[0] !== 3) {
|
||
// ignore frames with unrecognized character encodings
|
||
return;
|
||
}
|
||
|
||
for (i = 1; i < tag.data.length; i++) {
|
||
if (tag.data[i] === 0) {
|
||
// parse the description and URL fields
|
||
tag.description = parseUtf8(tag.data, 1, i);
|
||
tag.url = parseUtf8(tag.data, i + 1, tag.data.length);
|
||
break;
|
||
}
|
||
}
|
||
},
|
||
PRIV: function(tag) {
|
||
var i;
|
||
|
||
for (i = 0; i < tag.data.length; i++) {
|
||
if (tag.data[i] === 0) {
|
||
// parse the description and URL fields
|
||
tag.owner = parseIso88591(tag.data, 0, i);
|
||
break;
|
||
}
|
||
}
|
||
tag.privateData = tag.data.subarray(i + 1);
|
||
tag.data = tag.privateData;
|
||
}
|
||
},
|
||
MetadataStream;
|
||
|
||
MetadataStream = function(options) {
|
||
var
|
||
settings = {
|
||
debug: !!(options && options.debug),
|
||
|
||
// the bytes of the program-level descriptor field in MP2T
|
||
// see ISO/IEC 13818-1:2013 (E), section 2.6 "Program and
|
||
// program element descriptors"
|
||
descriptor: options && options.descriptor
|
||
},
|
||
// the total size in bytes of the ID3 tag being parsed
|
||
tagSize = 0,
|
||
// tag data that is not complete enough to be parsed
|
||
buffer = [],
|
||
// the total number of bytes currently in the buffer
|
||
bufferSize = 0,
|
||
i;
|
||
|
||
MetadataStream.prototype.init.call(this);
|
||
|
||
// calculate the text track in-band metadata track dispatch type
|
||
// https://html.spec.whatwg.org/multipage/embedded-content.html#steps-to-expose-a-media-resource-specific-text-track
|
||
this.dispatchType = StreamTypes.METADATA_STREAM_TYPE.toString(16);
|
||
if (settings.descriptor) {
|
||
for (i = 0; i < settings.descriptor.length; i++) {
|
||
this.dispatchType += ('00' + settings.descriptor[i].toString(16)).slice(-2);
|
||
}
|
||
}
|
||
|
||
this.push = function(chunk) {
|
||
var tag, frameStart, frameSize, frame, i, frameHeader;
|
||
if (chunk.type !== 'timed-metadata') {
|
||
return;
|
||
}
|
||
|
||
// if data_alignment_indicator is set in the PES header,
|
||
// we must have the start of a new ID3 tag. Assume anything
|
||
// remaining in the buffer was malformed and throw it out
|
||
if (chunk.dataAlignmentIndicator) {
|
||
bufferSize = 0;
|
||
buffer.length = 0;
|
||
}
|
||
|
||
// ignore events that don't look like ID3 data
|
||
if (buffer.length === 0 &&
|
||
(chunk.data.length < 10 ||
|
||
chunk.data[0] !== 'I'.charCodeAt(0) ||
|
||
chunk.data[1] !== 'D'.charCodeAt(0) ||
|
||
chunk.data[2] !== '3'.charCodeAt(0))) {
|
||
if (settings.debug) {
|
||
// eslint-disable-next-line no-console
|
||
console.log('Skipping unrecognized metadata packet');
|
||
}
|
||
return;
|
||
}
|
||
|
||
// add this chunk to the data we've collected so far
|
||
|
||
buffer.push(chunk);
|
||
bufferSize += chunk.data.byteLength;
|
||
|
||
// grab the size of the entire frame from the ID3 header
|
||
if (buffer.length === 1) {
|
||
// the frame size is transmitted as a 28-bit integer in the
|
||
// last four bytes of the ID3 header.
|
||
// The most significant bit of each byte is dropped and the
|
||
// results concatenated to recover the actual value.
|
||
tagSize = parseSyncSafeInteger(chunk.data.subarray(6, 10));
|
||
|
||
// ID3 reports the tag size excluding the header but it's more
|
||
// convenient for our comparisons to include it
|
||
tagSize += 10;
|
||
}
|
||
|
||
// if the entire frame has not arrived, wait for more data
|
||
if (bufferSize < tagSize) {
|
||
return;
|
||
}
|
||
|
||
// collect the entire frame so it can be parsed
|
||
tag = {
|
||
data: new Uint8Array(tagSize),
|
||
frames: [],
|
||
pts: buffer[0].pts,
|
||
dts: buffer[0].dts
|
||
};
|
||
for (i = 0; i < tagSize;) {
|
||
tag.data.set(buffer[0].data.subarray(0, tagSize - i), i);
|
||
i += buffer[0].data.byteLength;
|
||
bufferSize -= buffer[0].data.byteLength;
|
||
buffer.shift();
|
||
}
|
||
|
||
// find the start of the first frame and the end of the tag
|
||
frameStart = 10;
|
||
if (tag.data[5] & 0x40) {
|
||
// advance the frame start past the extended header
|
||
frameStart += 4; // header size field
|
||
frameStart += parseSyncSafeInteger(tag.data.subarray(10, 14));
|
||
|
||
// clip any padding off the end
|
||
tagSize -= parseSyncSafeInteger(tag.data.subarray(16, 20));
|
||
}
|
||
|
||
// parse one or more ID3 frames
|
||
// http://id3.org/id3v2.3.0#ID3v2_frame_overview
|
||
do {
|
||
// determine the number of bytes in this frame
|
||
frameSize = parseSyncSafeInteger(tag.data.subarray(frameStart + 4, frameStart + 8));
|
||
if (frameSize < 1) {
|
||
// eslint-disable-next-line no-console
|
||
return console.log('Malformed ID3 frame encountered. Skipping metadata parsing.');
|
||
}
|
||
frameHeader = String.fromCharCode(tag.data[frameStart],
|
||
tag.data[frameStart + 1],
|
||
tag.data[frameStart + 2],
|
||
tag.data[frameStart + 3]);
|
||
|
||
|
||
frame = {
|
||
id: frameHeader,
|
||
data: tag.data.subarray(frameStart + 10, frameStart + frameSize + 10)
|
||
};
|
||
frame.key = frame.id;
|
||
if (tagParsers[frame.id]) {
|
||
tagParsers[frame.id](frame);
|
||
|
||
// handle the special PRIV frame used to indicate the start
|
||
// time for raw AAC data
|
||
if (frame.owner === 'com.apple.streaming.transportStreamTimestamp') {
|
||
var
|
||
d = frame.data,
|
||
size = ((d[3] & 0x01) << 30) |
|
||
(d[4] << 22) |
|
||
(d[5] << 14) |
|
||
(d[6] << 6) |
|
||
(d[7] >>> 2);
|
||
|
||
size *= 4;
|
||
size += d[7] & 0x03;
|
||
frame.timeStamp = size;
|
||
// in raw AAC, all subsequent data will be timestamped based
|
||
// on the value of this frame
|
||
// we couldn't have known the appropriate pts and dts before
|
||
// parsing this ID3 tag so set those values now
|
||
if (tag.pts === undefined && tag.dts === undefined) {
|
||
tag.pts = frame.timeStamp;
|
||
tag.dts = frame.timeStamp;
|
||
}
|
||
this.trigger('timestamp', frame);
|
||
}
|
||
}
|
||
tag.frames.push(frame);
|
||
|
||
frameStart += 10; // advance past the frame header
|
||
frameStart += frameSize; // advance past the frame body
|
||
} while (frameStart < tagSize);
|
||
this.trigger('data', tag);
|
||
};
|
||
};
|
||
MetadataStream.prototype = new Stream();
|
||
|
||
module.exports = MetadataStream;
|
||
|
||
},{"../utils/stream":15,"./stream-types":12}],12:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
module.exports = {
|
||
H264_STREAM_TYPE: 0x1B,
|
||
ADTS_STREAM_TYPE: 0x0F,
|
||
METADATA_STREAM_TYPE: 0x15
|
||
};
|
||
|
||
},{}],13:[function(require,module,exports){
|
||
/**
|
||
* mux.js
|
||
*
|
||
* Copyright (c) 2016 Brightcove
|
||
* All rights reserved.
|
||
*
|
||
* Accepts program elementary stream (PES) data events and corrects
|
||
* decode and presentation time stamps to account for a rollover
|
||
* of the 33 bit value.
|
||
*/
|
||
|
||
'use strict';
|
||
|
||
var Stream = require('../utils/stream');
|
||
|
||
var MAX_TS = 8589934592;
|
||
|
||
var RO_THRESH = 4294967296;
|
||
|
||
var handleRollover = function(value, reference) {
|
||
var direction = 1;
|
||
|
||
if (value > reference) {
|
||
// If the current timestamp value is greater than our reference timestamp and we detect a
|
||
// timestamp rollover, this means the roll over is happening in the opposite direction.
|
||
// Example scenario: Enter a long stream/video just after a rollover occurred. The reference
|
||
// point will be set to a small number, e.g. 1. The user then seeks backwards over the
|
||
// rollover point. In loading this segment, the timestamp values will be very large,
|
||
// e.g. 2^33 - 1. Since this comes before the data we loaded previously, we want to adjust
|
||
// the time stamp to be `value - 2^33`.
|
||
direction = -1;
|
||
}
|
||
|
||
// Note: A seek forwards or back that is greater than the RO_THRESH (2^32, ~13 hours) will
|
||
// cause an incorrect adjustment.
|
||
while (Math.abs(reference - value) > RO_THRESH) {
|
||
value += (direction * MAX_TS);
|
||
}
|
||
|
||
return value;
|
||
};
|
||
|
||
var TimestampRolloverStream = function(type) {
|
||
var lastDTS, referenceDTS;
|
||
|
||
TimestampRolloverStream.prototype.init.call(this);
|
||
|
||
this.type_ = type;
|
||
|
||
this.push = function(data) {
|
||
if (data.type !== this.type_) {
|
||
return;
|
||
}
|
||
|
||
if (referenceDTS === undefined) {
|
||
referenceDTS = data.dts;
|
||
}
|
||
|
||
data.dts = handleRollover(data.dts, referenceDTS);
|
||
data.pts = handleRollover(data.pts, referenceDTS);
|
||
|
||
lastDTS = data.dts;
|
||
|
||
this.trigger('data', data);
|
||
};
|
||
|
||
this.flush = function() {
|
||
referenceDTS = lastDTS;
|
||
this.trigger('done');
|
||
};
|
||
|
||
this.discontinuity = function() {
|
||
referenceDTS = void 0;
|
||
lastDTS = void 0;
|
||
};
|
||
|
||
};
|
||
|
||
TimestampRolloverStream.prototype = new Stream();
|
||
|
||
module.exports = {
|
||
TimestampRolloverStream: TimestampRolloverStream,
|
||
handleRollover: handleRollover
|
||
};
|
||
|
||
},{"../utils/stream":15}],14:[function(require,module,exports){
|
||
'use strict';
|
||
|
||
var ExpGolomb;
|
||
|
||
/**
|
||
* Parser for exponential Golomb codes, a variable-bitwidth number encoding
|
||
* scheme used by h264.
|
||
*/
|
||
ExpGolomb = function(workingData) {
|
||
var
|
||
// the number of bytes left to examine in workingData
|
||
workingBytesAvailable = workingData.byteLength,
|
||
|
||
// the current word being examined
|
||
workingWord = 0, // :uint
|
||
|
||
// the number of bits left to examine in the current word
|
||
workingBitsAvailable = 0; // :uint;
|
||
|
||
// ():uint
|
||
this.length = function() {
|
||
return (8 * workingBytesAvailable);
|
||
};
|
||
|
||
// ():uint
|
||
this.bitsAvailable = function() {
|
||
return (8 * workingBytesAvailable) + workingBitsAvailable;
|
||
};
|
||
|
||
// ():void
|
||
this.loadWord = function() {
|
||
var
|
||
position = workingData.byteLength - workingBytesAvailable,
|
||
workingBytes = new Uint8Array(4),
|
||
availableBytes = Math.min(4, workingBytesAvailable);
|
||
|
||
if (availableBytes === 0) {
|
||
throw new Error('no bytes available');
|
||
}
|
||
|
||
workingBytes.set(workingData.subarray(position,
|
||
position + availableBytes));
|
||
workingWord = new DataView(workingBytes.buffer).getUint32(0);
|
||
|
||
// track the amount of workingData that has been processed
|
||
workingBitsAvailable = availableBytes * 8;
|
||
workingBytesAvailable -= availableBytes;
|
||
};
|
||
|
||
// (count:int):void
|
||
this.skipBits = function(count) {
|
||
var skipBytes; // :int
|
||
if (workingBitsAvailable > count) {
|
||
workingWord <<= count;
|
||
workingBitsAvailable -= count;
|
||
} else {
|
||
count -= workingBitsAvailable;
|
||
skipBytes = Math.floor(count / 8);
|
||
|
||
count -= (skipBytes * 8);
|
||
workingBytesAvailable -= skipBytes;
|
||
|
||
this.loadWord();
|
||
|
||
workingWord <<= count;
|
||
workingBitsAvailable -= count;
|
||
}
|
||
};
|
||
|
||
// (size:int):uint
|
||
this.readBits = function(size) {
|
||
var
|
||
bits = Math.min(workingBitsAvailable, size), // :uint
|
||
valu = workingWord >>> (32 - bits); // :uint
|
||
// if size > 31, handle error
|
||
workingBitsAvailable -= bits;
|
||
if (workingBitsAvailable > 0) {
|
||
workingWord <<= bits;
|
||
} else if (workingBytesAvailable > 0) {
|
||
this.loadWord();
|
||
}
|
||
|
||
bits = size - bits;
|
||
if (bits > 0) {
|
||
return valu << bits | this.readBits(bits);
|
||
}
|
||
return valu;
|
||
};
|
||
|
||
// ():uint
|
||
this.skipLeadingZeros = function() {
|
||
var leadingZeroCount; // :uint
|
||
for (leadingZeroCount = 0; leadingZeroCount < workingBitsAvailable; ++leadingZeroCount) {
|
||
if ((workingWord & (0x80000000 >>> leadingZeroCount)) !== 0) {
|
||
// the first bit of working word is 1
|
||
workingWord <<= leadingZeroCount;
|
||
workingBitsAvailable -= leadingZeroCount;
|
||
return leadingZeroCount;
|
||
}
|
||
}
|
||
|
||
// we exhausted workingWord and still have not found a 1
|
||
this.loadWord();
|
||
return leadingZeroCount + this.skipLeadingZeros();
|
||
};
|
||
|
||
// ():void
|
||
this.skipUnsignedExpGolomb = function() {
|
||
this.skipBits(1 + this.skipLeadingZeros());
|
||
};
|
||
|
||
// ():void
|
||
this.skipExpGolomb = function() {
|
||
this.skipBits(1 + this.skipLeadingZeros());
|
||
};
|
||
|
||
// ():uint
|
||
this.readUnsignedExpGolomb = function() {
|
||
var clz = this.skipLeadingZeros(); // :uint
|
||
return this.readBits(clz + 1) - 1;
|
||
};
|
||
|
||
// ():int
|
||
this.readExpGolomb = function() {
|
||
var valu = this.readUnsignedExpGolomb(); // :int
|
||
if (0x01 & valu) {
|
||
// the number is odd if the low order bit is set
|
||
return (1 + valu) >>> 1; // add 1 to make it even, and divide by 2
|
||
}
|
||
return -1 * (valu >>> 1); // divide by two then make it negative
|
||
};
|
||
|
||
// Some convenience functions
|
||
// :Boolean
|
||
this.readBoolean = function() {
|
||
return this.readBits(1) === 1;
|
||
};
|
||
|
||
// ():int
|
||
this.readUnsignedByte = function() {
|
||
return this.readBits(8);
|
||
};
|
||
|
||
this.loadWord();
|
||
};
|
||
|
||
module.exports = ExpGolomb;
|
||
|
||
},{}],15:[function(require,module,exports){
|
||
/**
|
||
* mux.js
|
||
*
|
||
* Copyright (c) 2014 Brightcove
|
||
* All rights reserved.
|
||
*
|
||
* A lightweight readable stream implemention that handles event dispatching.
|
||
* Objects that inherit from streams should call init in their constructors.
|
||
*/
|
||
'use strict';
|
||
|
||
var Stream = function() {
|
||
this.init = function() {
|
||
var listeners = {};
|
||
/**
|
||
* Add a listener for a specified event type.
|
||
* @param type {string} the event name
|
||
* @param listener {function} the callback to be invoked when an event of
|
||
* the specified type occurs
|
||
*/
|
||
this.on = function(type, listener) {
|
||
if (!listeners[type]) {
|
||
listeners[type] = [];
|
||
}
|
||
listeners[type] = listeners[type].concat(listener);
|
||
};
|
||
/**
|
||
* Remove a listener for a specified event type.
|
||
* @param type {string} the event name
|
||
* @param listener {function} a function previously registered for this
|
||
* type of event through `on`
|
||
*/
|
||
this.off = function(type, listener) {
|
||
var index;
|
||
if (!listeners[type]) {
|
||
return false;
|
||
}
|
||
index = listeners[type].indexOf(listener);
|
||
listeners[type] = listeners[type].slice();
|
||
listeners[type].splice(index, 1);
|
||
return index > -1;
|
||
};
|
||
/**
|
||
* Trigger an event of the specified type on this stream. Any additional
|
||
* arguments to this function are passed as parameters to event listeners.
|
||
* @param type {string} the event name
|
||
*/
|
||
this.trigger = function(type) {
|
||
var callbacks, i, length, args;
|
||
callbacks = listeners[type];
|
||
if (!callbacks) {
|
||
return;
|
||
}
|
||
// Slicing the arguments on every invocation of this method
|
||
// can add a significant amount of overhead. Avoid the
|
||
// intermediate object creation for the common case of a
|
||
// single callback argument
|
||
if (arguments.length === 2) {
|
||
length = callbacks.length;
|
||
for (i = 0; i < length; ++i) {
|
||
callbacks[i].call(this, arguments[1]);
|
||
}
|
||
} else {
|
||
args = [];
|
||
i = arguments.length;
|
||
for (i = 1; i < arguments.length; ++i) {
|
||
args.push(arguments[i]);
|
||
}
|
||
length = callbacks.length;
|
||
for (i = 0; i < length; ++i) {
|
||
callbacks[i].apply(this, args);
|
||
}
|
||
}
|
||
};
|
||
/**
|
||
* Destroys the stream and cleans up.
|
||
*/
|
||
this.dispose = function() {
|
||
listeners = {};
|
||
};
|
||
};
|
||
};
|
||
|
||
/**
|
||
* Forwards all `data` events on this stream to the destination stream. The
|
||
* destination stream should provide a method `push` to receive the data
|
||
* events as they arrive.
|
||
* @param destination {stream} the stream that will receive all `data` events
|
||
* @param autoFlush {boolean} if false, we will not call `flush` on the destination
|
||
* when the current stream emits a 'done' event
|
||
* @see http://nodejs.org/api/stream.html#stream_readable_pipe_destination_options
|
||
*/
|
||
Stream.prototype.pipe = function(destination) {
|
||
this.on('data', function(data) {
|
||
destination.push(data);
|
||
});
|
||
|
||
this.on('done', function(flushSource) {
|
||
destination.flush(flushSource);
|
||
});
|
||
|
||
return destination;
|
||
};
|
||
|
||
// Default stream functions that are expected to be overridden to perform
|
||
// actual work. These are provided by the prototype as a sort of no-op
|
||
// implementation so that we don't have to check for their existence in the
|
||
// `pipe` function above.
|
||
Stream.prototype.push = function(data) {
|
||
this.trigger('data', data);
|
||
};
|
||
|
||
Stream.prototype.flush = function(flushSource) {
|
||
this.trigger('done', flushSource);
|
||
};
|
||
|
||
module.exports = Stream;
|
||
|
||
},{}]},{},[6])(6)
|
||
}); |