852 lines
27 KiB
JavaScript
852 lines
27 KiB
JavaScript
/*jslint plusplus: true */
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/*jslint nomen: true*/
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/**
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* Created by gp on 11/08/14.
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*/
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function Simulcast() {
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"use strict";
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// TODO(gp) split the Simulcast class in two classes : NativeSimulcast and ClassicSimulcast.
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this.debugLvl = 1;
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}
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(function () {
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"use strict";
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// global state for all transformers.
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var localExplosionMap = {}, localVideoSourceCache, emptyCompoundIndex,
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remoteVideoSourceCache, remoteMaps = {
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msid2Quality: {},
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ssrc2Msid: {},
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receivingVideoStreams: {}
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}, localMaps = {
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msids: [],
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msid2ssrc: {}
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};
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Simulcast.prototype._generateGuid = (function () {
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function s4() {
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return Math.floor((1 + Math.random()) * 0x10000)
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.toString(16)
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.substring(1);
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}
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return function () {
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return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
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s4() + '-' + s4() + s4() + s4();
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};
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}());
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Simulcast.prototype._cacheVideoSources = function (lines) {
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localVideoSourceCache = this._getVideoSources(lines);
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};
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Simulcast.prototype._restoreVideoSources = function (lines) {
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this._replaceVideoSources(lines, localVideoSourceCache);
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};
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Simulcast.prototype._cacheRemoteVideoSources = function (lines) {
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remoteVideoSourceCache = this._getVideoSources(lines);
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};
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Simulcast.prototype._restoreRemoteVideoSources = function (lines) {
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this._replaceVideoSources(lines, remoteVideoSourceCache);
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};
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Simulcast.prototype._replaceVideoSources = function (lines, videoSources) {
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var i, inVideo = false, index = -1, howMany = 0;
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if (this.debugLvl) {
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console.info('Replacing video sources...');
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}
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for (i = 0; i < lines.length; i++) {
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if (inVideo && lines[i].substring(0, 'm='.length) === 'm=') {
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// Out of video.
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break;
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}
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if (!inVideo && lines[i].substring(0, 'm=video '.length) === 'm=video ') {
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// In video.
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inVideo = true;
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}
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if (inVideo && (lines[i].substring(0, 'a=ssrc:'.length) === 'a=ssrc:'
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|| lines[i].substring(0, 'a=ssrc-group:'.length) === 'a=ssrc-group:')) {
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if (index === -1) {
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index = i;
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}
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howMany++;
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}
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}
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// efficiency baby ;)
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lines.splice.apply(lines,
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[index, howMany].concat(videoSources));
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};
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Simulcast.prototype._getVideoSources = function (lines) {
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var i, inVideo = false, sb = [];
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if (this.debugLvl) {
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console.info('Getting video sources...');
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}
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for (i = 0; i < lines.length; i++) {
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if (inVideo && lines[i].substring(0, 'm='.length) === 'm=') {
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// Out of video.
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break;
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}
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if (!inVideo && lines[i].substring(0, 'm=video '.length) === 'm=video ') {
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// In video.
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inVideo = true;
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}
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if (inVideo && lines[i].substring(0, 'a=ssrc:'.length) === 'a=ssrc:') {
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// In SSRC.
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sb.push(lines[i]);
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}
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if (inVideo && lines[i].substring(0, 'a=ssrc-group:'.length) === 'a=ssrc-group:') {
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sb.push(lines[i]);
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}
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}
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return sb;
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};
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Simulcast.prototype._parseMedia = function (lines, mediatypes) {
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var i, res = [], type, cur_media, idx, ssrcs, cur_ssrc, ssrc,
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ssrc_attribute, group, semantics, skip;
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if (this.debugLvl) {
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console.info('Parsing media sources...');
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}
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for (i = 0; i < lines.length; i++) {
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if (lines[i].substring(0, 'm='.length) === 'm=') {
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type = lines[i]
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.substr('m='.length, lines[i].indexOf(' ') - 'm='.length);
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skip = mediatypes !== undefined && mediatypes.indexOf(type) === -1;
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if (!skip) {
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cur_media = {
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'type': type,
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'sources': {},
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'groups': []
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};
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res.push(cur_media);
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}
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} else if (!skip && lines[i].substring(0, 'a=ssrc:'.length) === 'a=ssrc:') {
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idx = lines[i].indexOf(' ');
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ssrc = lines[i].substring('a=ssrc:'.length, idx);
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if (cur_media.sources[ssrc] === undefined) {
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cur_ssrc = {'ssrc': ssrc};
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cur_media.sources[ssrc] = cur_ssrc;
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}
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ssrc_attribute = lines[i].substr(idx + 1).split(':', 2)[0];
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cur_ssrc[ssrc_attribute] = lines[i].substr(idx + 1).split(':', 2)[1];
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if (cur_media.base === undefined) {
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cur_media.base = cur_ssrc;
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}
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} else if (!skip && lines[i].substring(0, 'a=ssrc-group:'.length) === 'a=ssrc-group:') {
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idx = lines[i].indexOf(' ');
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semantics = lines[i].substr(0, idx).substr('a=ssrc-group:'.length);
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ssrcs = lines[i].substr(idx).trim().split(' ');
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group = {
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'semantics': semantics,
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'ssrcs': ssrcs
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};
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cur_media.groups.push(group);
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} else if (!skip && (lines[i].substring(0, 'a=sendrecv'.length) === 'a=sendrecv' ||
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lines[i].substring(0, 'a=recvonly'.length) === 'a=recvonly' ||
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lines[i].substring(0, 'a=sendonly'.length) === 'a=sendonly' ||
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lines[i].substring(0, 'a=inactive'.length) === 'a=inactive')) {
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cur_media.direction = lines[i].substring('a='.length, 8);
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}
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}
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return res;
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};
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// Returns a random integer between min (included) and max (excluded)
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// Using Math.round() will give you a non-uniform distribution!
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Simulcast.prototype._generateRandomSSRC = function () {
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var min = 0, max = 0xffffffff;
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return Math.floor(Math.random() * (max - min)) + min;
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};
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function CompoundIndex(obj) {
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if (obj !== undefined) {
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this.row = obj.row;
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this.column = obj.column;
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}
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}
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emptyCompoundIndex = new CompoundIndex();
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Simulcast.prototype._indexOfArray = function (needle, haystack, start) {
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var length = haystack.length, idx, i;
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if (!start) {
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start = 0;
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}
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for (i = start; i < length; i++) {
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idx = haystack[i].indexOf(needle);
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if (idx !== -1) {
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return new CompoundIndex({row: i, column: idx});
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}
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}
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return emptyCompoundIndex;
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};
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Simulcast.prototype._removeSimulcastGroup = function (lines) {
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var i;
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for (i = lines.length - 1; i >= 0; i--) {
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if (lines[i].indexOf('a=ssrc-group:SIM') !== -1) {
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lines.splice(i, 1);
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}
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}
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};
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/**
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* Produces a single stream with multiple tracks for local video sources.
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*
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* @param lines
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* @private
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*/
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Simulcast.prototype._explodeLocalSimulcastSources = function (lines) {
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var sb, msid, sid, tid, videoSources, self;
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if (this.debugLvl) {
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console.info('Exploding local video sources...');
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}
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videoSources = this._parseMedia(lines, ['video'])[0];
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self = this;
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if (videoSources.groups && videoSources.groups.length !== 0) {
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videoSources.groups.forEach(function (group) {
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if (group.semantics === 'SIM') {
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group.ssrcs.forEach(function (ssrc) {
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// Get the msid for this ssrc..
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if (localExplosionMap[ssrc]) {
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// .. either from the explosion map..
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msid = localExplosionMap[ssrc];
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} else {
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// .. or generate a new one (msid).
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sid = videoSources.sources[ssrc].msid
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.substring(0, videoSources.sources[ssrc].msid.indexOf(' '));
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tid = self._generateGuid();
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msid = [sid, tid].join(' ');
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localExplosionMap[ssrc] = msid;
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}
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// Assign it to the source object.
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videoSources.sources[ssrc].msid = msid;
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// TODO(gp) Change the msid of associated sources.
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});
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}
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});
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}
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sb = this._compileVideoSources(videoSources);
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this._replaceVideoSources(lines, sb);
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};
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/**
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* Groups local video sources together in the ssrc-group:SIM group.
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*
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* @param lines
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* @private
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*/
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Simulcast.prototype._groupLocalVideoSources = function (lines) {
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var sb, videoSources, ssrcs = [], ssrc;
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if (this.debugLvl) {
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console.info('Grouping local video sources...');
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}
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videoSources = this._parseMedia(lines, ['video'])[0];
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for (ssrc in videoSources.sources) {
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// jitsi-meet destroys/creates streams at various places causing
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// the original local stream ids to change. The only thing that
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// remains unchanged is the trackid.
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localMaps.msid2ssrc[videoSources.sources[ssrc].msid.split(' ')[1]] = ssrc;
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}
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// TODO(gp) add only "free" sources.
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localMaps.msids.forEach(function (msid) {
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ssrcs.push(localMaps.msid2ssrc[msid]);
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});
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if (!videoSources.groups) {
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videoSources.groups = [];
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}
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videoSources.groups.push({
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'semantics': 'SIM',
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'ssrcs': ssrcs
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});
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sb = this._compileVideoSources(videoSources);
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this._replaceVideoSources(lines, sb);
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};
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Simulcast.prototype._appendSimulcastGroup = function (lines) {
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var videoSources, ssrcGroup, simSSRC, numOfSubs = 3, i, sb, msid;
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if (this.debugLvl) {
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console.info('Appending simulcast group...');
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}
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// Get the primary SSRC information.
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videoSources = this._parseMedia(lines, ['video'])[0];
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// Start building the SIM SSRC group.
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ssrcGroup = ['a=ssrc-group:SIM'];
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// The video source buffer.
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sb = [];
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// Create the simulcast sub-streams.
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for (i = 0; i < numOfSubs; i++) {
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// TODO(gp) prevent SSRC collision.
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simSSRC = this._generateRandomSSRC();
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ssrcGroup.push(simSSRC);
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sb.splice.apply(sb, [sb.length, 0].concat(
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[["a=ssrc:", simSSRC, " cname:", videoSources.base.cname].join(''),
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["a=ssrc:", simSSRC, " msid:", videoSources.base.msid].join('')]
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));
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if (this.debugLvl) {
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console.info(['Generated substream ', i, ' with SSRC ', simSSRC, '.'].join(''));
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}
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}
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// Add the group sim layers.
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sb.splice(0, 0, ssrcGroup.join(' '))
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this._replaceVideoSources(lines, sb);
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};
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// Does the actual patching.
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Simulcast.prototype._ensureSimulcastGroup = function (lines) {
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if (this.debugLvl) {
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console.info('Ensuring simulcast group...');
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}
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if (this._indexOfArray('a=ssrc-group:SIM', lines) === emptyCompoundIndex) {
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this._appendSimulcastGroup(lines);
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this._cacheVideoSources(lines);
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} else {
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// verify that the ssrcs participating in the SIM group are present
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// in the SDP (needed for presence).
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this._restoreVideoSources(lines);
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}
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};
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Simulcast.prototype._ensureGoogConference = function (lines) {
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var sb;
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if (this.debugLvl) {
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console.info('Ensuring x-google-conference flag...')
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}
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if (this._indexOfArray('a=x-google-flag:conference', lines) === emptyCompoundIndex) {
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// Add the google conference flag
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sb = this._getVideoSources(lines);
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sb = ['a=x-google-flag:conference'].concat(sb);
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this._replaceVideoSources(lines, sb);
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}
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};
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Simulcast.prototype._compileVideoSources = function (videoSources) {
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var sb = [], ssrc, addedSSRCs = [];
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if (this.debugLvl) {
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console.info('Compiling video sources...');
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}
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// Add the groups
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if (videoSources.groups && videoSources.groups.length !== 0) {
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videoSources.groups.forEach(function (group) {
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if (group.ssrcs && group.ssrcs.length !== 0) {
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sb.push([['a=ssrc-group:', group.semantics].join(''), group.ssrcs.join(' ')].join(' '));
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// if (group.semantics !== 'SIM') {
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group.ssrcs.forEach(function (ssrc) {
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addedSSRCs.push(ssrc);
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sb.splice.apply(sb, [sb.length, 0].concat([
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["a=ssrc:", ssrc, " cname:", videoSources.sources[ssrc].cname].join(''),
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["a=ssrc:", ssrc, " msid:", videoSources.sources[ssrc].msid].join('')]));
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});
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//}
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}
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});
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}
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// Then add any free sources.
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if (videoSources.sources) {
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for (ssrc in videoSources.sources) {
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if (addedSSRCs.indexOf(ssrc) === -1) {
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sb.splice.apply(sb, [sb.length, 0].concat([
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["a=ssrc:", ssrc, " cname:", videoSources.sources[ssrc].cname].join(''),
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["a=ssrc:", ssrc, " msid:", videoSources.sources[ssrc].msid].join('')]));
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}
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}
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}
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return sb;
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};
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/**
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* Ensures that the simulcast group is present in the answer, _if_ native
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* simulcast is enabled,
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*
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* @param desc
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* @returns {*}
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*/
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Simulcast.prototype.transformAnswer = function (desc) {
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if (config.enableSimulcast && config.useNativeSimulcast) {
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var sb = desc.sdp.split('\r\n');
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// Even if we have enabled native simulcasting previously
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// (with a call to SLD with an appropriate SDP, for example),
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// createAnswer seems to consistently generate incomplete SDP
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// with missing SSRCS.
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//
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// So, subsequent calls to SLD will have missing SSRCS and presence
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// won't have the complete list of SRCs.
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this._ensureSimulcastGroup(sb);
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desc = new RTCSessionDescription({
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type: desc.type,
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sdp: sb.join('\r\n')
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});
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if (this.debugLvl && this.debugLvl > 1) {
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console.info('Transformed answer');
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console.info(desc.sdp);
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}
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}
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return desc;
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};
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Simulcast.prototype._restoreSimulcastGroups = function (sb) {
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this._restoreRemoteVideoSources(sb);
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};
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/**
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* Restores the simulcast groups of the remote description. In
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* transformRemoteDescription we remove those in order for the set remote
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* description to succeed. The focus needs the signal the groups to new
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* participants.
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*
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* @param desc
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* @returns {*}
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*/
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Simulcast.prototype.reverseTransformRemoteDescription = function (desc) {
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var sb;
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if (!desc || desc == null) {
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return desc;
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}
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if (config.enableSimulcast) {
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sb = desc.sdp.split('\r\n');
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this._restoreSimulcastGroups(sb);
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desc = new RTCSessionDescription({
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type: desc.type,
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sdp: sb.join('\r\n')
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});
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}
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return desc;
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};
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/**
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* Prepares the local description for public usage (i.e. to be signaled
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* through Jingle to the focus).
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*
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* @param desc
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* @returns {RTCSessionDescription}
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*/
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Simulcast.prototype.reverseTransformLocalDescription = function (desc) {
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var sb;
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if (!desc || desc == null) {
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return desc;
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}
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if (config.enableSimulcast) {
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if (config.useNativeSimulcast) {
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sb = desc.sdp.split('\r\n');
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this._explodeLocalSimulcastSources(sb);
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desc = new RTCSessionDescription({
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type: desc.type,
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sdp: sb.join('\r\n')
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});
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if (this.debugLvl && this.debugLvl > 1) {
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console.info('Exploded local video sources');
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console.info(desc.sdp);
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}
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} else {
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sb = desc.sdp.split('\r\n');
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this._groupLocalVideoSources(sb);
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desc = new RTCSessionDescription({
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type: desc.type,
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sdp: sb.join('\r\n')
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});
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if (this.debugLvl && this.debugLvl > 1) {
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console.info('Grouped local video sources');
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console.info(desc.sdp);
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}
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}
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}
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return desc;
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};
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Simulcast.prototype._ensureOrder = function (lines) {
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var videoSources, sb;
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videoSources = this._parseMedia(lines, ['video'])[0];
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|
sb = this._compileVideoSources(videoSources);
|
|
|
|
this._replaceVideoSources(lines, sb);
|
|
};
|
|
|
|
Simulcast.prototype._updateRemoteMaps = function (lines) {
|
|
var remoteVideoSources = this._parseMedia(lines, ['video'])[0], videoSource, quality;
|
|
|
|
// (re) initialize the remote maps.
|
|
remoteMaps = {
|
|
msid2Quality: {},
|
|
ssrc2Msid: {},
|
|
receivingVideoStreams: {}
|
|
};
|
|
|
|
if (remoteVideoSources.groups && remoteVideoSources.groups.length !== 0) {
|
|
remoteVideoSources.groups.forEach(function (group) {
|
|
if (group.semantics === 'SIM' && group.ssrcs && group.ssrcs.length !== 0) {
|
|
quality = 0;
|
|
group.ssrcs.forEach(function (ssrc) {
|
|
videoSource = remoteVideoSources.sources[ssrc];
|
|
remoteMaps.msid2Quality[videoSource.msid] = quality++;
|
|
remoteMaps.ssrc2Msid[videoSource.ssrc] = videoSource.msid;
|
|
});
|
|
}
|
|
});
|
|
}
|
|
};
|
|
|
|
/**
|
|
*
|
|
*
|
|
* @param desc
|
|
* @returns {*}
|
|
*/
|
|
Simulcast.prototype.transformLocalDescription = function (desc) {
|
|
if (config.enableSimulcast && !config.useNativeSimulcast) {
|
|
|
|
var sb = desc.sdp.split('\r\n');
|
|
|
|
this._removeSimulcastGroup(sb);
|
|
|
|
desc = new RTCSessionDescription({
|
|
type: desc.type,
|
|
sdp: sb.join('\r\n')
|
|
});
|
|
|
|
if (this.debugLvl && this.debugLvl > 1) {
|
|
console.info('Transformed local description');
|
|
console.info(desc.sdp);
|
|
}
|
|
}
|
|
|
|
return desc;
|
|
};
|
|
|
|
/**
|
|
* Removes the ssrc-group:SIM from the remote description bacause Chrome
|
|
* either gets confused and thinks this is an FID group or, if an FID group
|
|
* is already present, it fails to set the remote description.
|
|
*
|
|
* @param desc
|
|
* @returns {*}
|
|
*/
|
|
Simulcast.prototype.transformRemoteDescription = function (desc) {
|
|
if (config.enableSimulcast) {
|
|
|
|
var sb = desc.sdp.split('\r\n');
|
|
|
|
this._updateRemoteMaps(sb);
|
|
this._cacheRemoteVideoSources(sb);
|
|
this._removeSimulcastGroup(sb); // NOTE(gp) this needs to be called after updateRemoteMaps because we need the simulcast group in the _updateRemoteMaps() method.
|
|
|
|
if (config.useNativeSimulcast) {
|
|
// We don't need the goog conference flag if we're not doing
|
|
// native simulcast.
|
|
this._ensureGoogConference(sb);
|
|
}
|
|
|
|
desc = new RTCSessionDescription({
|
|
type: desc.type,
|
|
sdp: sb.join('\r\n')
|
|
});
|
|
|
|
if (this.debugLvl && this.debugLvl > 1) {
|
|
console.info('Transformed remote description');
|
|
console.info(desc.sdp);
|
|
}
|
|
}
|
|
|
|
return desc;
|
|
};
|
|
|
|
Simulcast.prototype._setReceivingVideoStream = function (ssrc) {
|
|
var receivingTrack = remoteMaps.ssrc2Msid[ssrc],
|
|
msidParts = receivingTrack.split(' ');
|
|
|
|
remoteMaps.receivingVideoStreams[msidParts[0]] = msidParts[1];
|
|
};
|
|
|
|
/**
|
|
* Returns a stream with single video track, the one currently being
|
|
* received by this endpoint.
|
|
*
|
|
* @param stream the remote simulcast stream.
|
|
* @returns {webkitMediaStream}
|
|
*/
|
|
Simulcast.prototype.getReceivingVideoStream = function (stream) {
|
|
var tracks, i, electedTrack, msid, quality = 1, receivingTrackId;
|
|
|
|
if (config.enableSimulcast) {
|
|
|
|
if (remoteMaps.receivingVideoStreams[stream.id])
|
|
{
|
|
// the bridge has signaled us to receive a specific track.
|
|
receivingTrackId = remoteMaps.receivingVideoStreams[stream.id];
|
|
tracks = stream.getVideoTracks();
|
|
for (i = 0; i < tracks.length; i++) {
|
|
if (receivingTrackId === tracks[i].id) {
|
|
electedTrack = tracks[i];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!electedTrack) {
|
|
// we don't have an elected track, choose by initial quality.
|
|
tracks = stream.getVideoTracks();
|
|
for (i = 0; i < tracks.length; i++) {
|
|
msid = [stream.id, tracks[i].id].join(' ');
|
|
if (remoteMaps.msid2Quality[msid] === quality) {
|
|
electedTrack = tracks[i];
|
|
break;
|
|
}
|
|
}
|
|
|
|
// TODO(gp) if the initialQuality could not be satisfied, lower
|
|
// the requirement and try again.
|
|
}
|
|
}
|
|
|
|
return (electedTrack)
|
|
? new webkitMediaStream([electedTrack])
|
|
: stream;
|
|
};
|
|
|
|
var stream;
|
|
|
|
/**
|
|
* GUM for simulcast.
|
|
*
|
|
* @param constraints
|
|
* @param success
|
|
* @param err
|
|
*/
|
|
Simulcast.prototype.getUserMedia = function (constraints, success, err) {
|
|
|
|
// TODO(gp) what if we request a resolution not supported by the hardware?
|
|
// TODO(gp) make the lq stream configurable; although this wouldn't work with native simulcast
|
|
var lqConstraints = {
|
|
audio: false,
|
|
video: {
|
|
mandatory: {
|
|
maxWidth: 320,
|
|
maxHeight: 180
|
|
}
|
|
}
|
|
};
|
|
|
|
if (config.enableSimulcast && !config.useNativeSimulcast) {
|
|
|
|
// NOTE(gp) if we request the lq stream first webkitGetUserMedia
|
|
// fails randomly. Tested with Chrome 37. As fippo suggested, the
|
|
// reason appears to be that Chrome only acquires the cam once and
|
|
// then downscales the picture (https://code.google.com/p/chromium/issues/detail?id=346616#c11)
|
|
|
|
navigator.webkitGetUserMedia(constraints, function (hqStream) {
|
|
|
|
// reset local maps.
|
|
localMaps.msids = [];
|
|
localMaps.msid2ssrc = {};
|
|
|
|
// add hq trackid to local map
|
|
localMaps.msids.push(hqStream.getVideoTracks()[0].id);
|
|
|
|
navigator.webkitGetUserMedia(lqConstraints, function (lqStream) {
|
|
|
|
// NOTE(gp) The specification says Array.forEach() will visit
|
|
// the array elements in numeric order, and that it doesn't
|
|
// visit elements that don't exist.
|
|
|
|
// add lq trackid to local map
|
|
localMaps.msids.splice(0, 0, lqStream.getVideoTracks()[0].id);
|
|
|
|
hqStream.addTrack(lqStream.getVideoTracks()[0]);
|
|
stream = hqStream;
|
|
success(hqStream);
|
|
}, err);
|
|
}, err);
|
|
} else {
|
|
|
|
// There's nothing special to do for native simulcast, so just do a normal GUM.
|
|
|
|
navigator.webkitGetUserMedia(constraints, function (hqStream) {
|
|
|
|
// reset local maps.
|
|
localMaps.msids = [];
|
|
localMaps.msid2ssrc = {};
|
|
|
|
// add hq stream to local map
|
|
localMaps.msids.push(hqStream.getVideoTracks()[0].id);
|
|
stream = hqStream;
|
|
success(hqStream);
|
|
}, err);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Gets the fully qualified msid (stream.id + track.id) associated to the
|
|
* SSRC.
|
|
*
|
|
* @param ssrc
|
|
* @returns {*}
|
|
*/
|
|
Simulcast.prototype.getRemoteVideoStreamIdBySSRC = function (ssrc) {
|
|
return remoteMaps.ssrc2Msid[ssrc];
|
|
};
|
|
|
|
Simulcast.prototype.parseMedia = function (desc, mediatypes) {
|
|
var lines = desc.sdp.split('\r\n');
|
|
return this._parseMedia(lines, mediatypes);
|
|
};
|
|
|
|
Simulcast.prototype._startLocalVideoStream = function (ssrc) {
|
|
var trackid;
|
|
|
|
Object.keys(localMaps.msid2ssrc).some(function (tid) {
|
|
if (localMaps.msid2ssrc[tid] == ssrc)
|
|
{
|
|
trackid = tid;
|
|
return true;
|
|
}
|
|
});
|
|
|
|
stream.getVideoTracks().some(function(track) {
|
|
if (track.id === trackid) {
|
|
track.enabled = true;
|
|
return true;
|
|
}
|
|
});
|
|
};
|
|
|
|
Simulcast.prototype._stopLocalVideoStream = function (ssrc) {
|
|
var trackid;
|
|
|
|
Object.keys(localMaps.msid2ssrc).some(function (tid) {
|
|
if (localMaps.msid2ssrc[tid] == ssrc)
|
|
{
|
|
trackid = tid;
|
|
return true;
|
|
}
|
|
});
|
|
|
|
stream.getVideoTracks().some(function(track) {
|
|
if (track.id === trackid) {
|
|
track.enabled = false;
|
|
return true;
|
|
}
|
|
});
|
|
};
|
|
|
|
Simulcast.prototype.getLocalVideoStream = function() {
|
|
var track;
|
|
|
|
stream.getVideoTracks().some(function(t) {
|
|
if ((track = t).enabled) {
|
|
return true;
|
|
}
|
|
});
|
|
|
|
return new webkitMediaStream([track]);
|
|
};
|
|
|
|
$(document).bind('simulcastlayerschanged', function (event, endpointSimulcastLayers) {
|
|
endpointSimulcastLayers.forEach(function (esl) {
|
|
var ssrc = esl.simulcastLayer.primarySSRC;
|
|
var simulcast = new Simulcast();
|
|
simulcast._setReceivingVideoStream(ssrc);
|
|
});
|
|
});
|
|
|
|
$(document).bind('startsimulcastlayer', function(event, simulcastLayer) {
|
|
var ssrc = simulcastLayer.primarySSRC;
|
|
var simulcast = new Simulcast();
|
|
simulcast._startLocalVideoStream(ssrc);
|
|
$(document).trigger('simulcastlayerstarted');
|
|
});
|
|
|
|
$(document).bind('stopsimulcastlayer', function(event, simulcastLayer) {
|
|
var ssrc = simulcastLayer.primarySSRC;
|
|
var simulcast = new Simulcast();
|
|
simulcast._stopLocalVideoStream(ssrc);
|
|
$(document).trigger('simulcastlayerstopped');
|
|
});
|
|
}());
|