@l5i/dashjs/build/es5/src/dash/WebmSegmentBaseLoader.js

A reference client implementation for the playback of MPEG DASH via Javascript and compliant browsers.

'use strict';Object.defineProperty(exports,'__esModule',{value:true});function _interopRequireDefault(obj){return obj && obj.__esModule?obj:{'default':obj};}var _coreEventsEvents=require('../core/events/Events');var _coreEventsEvents2=_interopRequireDefault(_coreEventsEvents);var _coreEventBus=require('../core/EventBus');var _coreEventBus2=_interopRequireDefault(_coreEventBus);var _streamingUtilsEBMLParser=require('../streaming/utils/EBMLParser');var _streamingUtilsEBMLParser2=_interopRequireDefault(_streamingUtilsEBMLParser);var _coreFactoryMaker=require('../core/FactoryMaker');var _coreFactoryMaker2=_interopRequireDefault(_coreFactoryMaker);var _coreDebug=require('../core/Debug');var _coreDebug2=_interopRequireDefault(_coreDebug);var _streamingUtilsRequestModifier=require('../streaming/utils/RequestModifier');var _streamingUtilsRequestModifier2=_interopRequireDefault(_streamingUtilsRequestModifier);var _voSegment=require('./vo/Segment');var _voSegment2=_interopRequireDefault(_voSegment);var _streamingVoMetricsHTTPRequest=require('../streaming/vo/metrics/HTTPRequest');var _streamingVoFragmentRequest=require('../streaming/vo/FragmentRequest');var _streamingVoFragmentRequest2=_interopRequireDefault(_streamingVoFragmentRequest);var _streamingNetHTTPLoader=require('../streaming/net/HTTPLoader');var _streamingNetHTTPLoader2=_interopRequireDefault(_streamingNetHTTPLoader);var _streamingVoDashJSError=require('../streaming/vo/DashJSError');var _streamingVoDashJSError2=_interopRequireDefault(_streamingVoDashJSError);var _coreErrorsErrors=require('../core/errors/Errors');var _coreErrorsErrors2=_interopRequireDefault(_coreErrorsErrors);function WebmSegmentBaseLoader(){var context=this.context;var eventBus=(0,_coreEventBus2['default'])(context).getInstance();var instance=undefined,logger=undefined,WebM=undefined,errHandler=undefined,requestModifier=undefined,metricsModel=undefined,mediaPlayerModel=undefined,httpLoader=undefined,baseURLController=undefined;function setup(){logger = (0,_coreDebug2['default'])(context).getInstance().getLogger(instance);WebM = {EBML:{tag:0x1A45DFA3,required:true},Segment:{tag:0x18538067,required:true,SeekHead:{tag:0x114D9B74,required:true},Info:{tag:0x1549A966,required:true,TimecodeScale:{tag:0x2AD7B1,required:true,parse:'getMatroskaUint'},Duration:{tag:0x4489,required:true,parse:'getMatroskaFloat'}},Tracks:{tag:0x1654AE6B,required:true},Cues:{tag:0x1C53BB6B,required:true,CuePoint:{tag:0xBB,required:true,CueTime:{tag:0xB3,required:true,parse:'getMatroskaUint'},CueTrackPositions:{tag:0xB7,required:true,CueTrack:{tag:0xF7,required:true,parse:'getMatroskaUint'},CueClusterPosition:{tag:0xF1,required:true,parse:'getMatroskaUint'}}}}},Void:{tag:0xEC,required:true}};}function initialize(){requestModifier = (0,_streamingUtilsRequestModifier2['default'])(context).getInstance();httpLoader = (0,_streamingNetHTTPLoader2['default'])(context).create({errHandler:errHandler,metricsModel:metricsModel,mediaPlayerModel:mediaPlayerModel,requestModifier:requestModifier});}function setConfig(config){if(!config.baseURLController || !config.metricsModel || !config.mediaPlayerModel || !config.errHandler){throw new Error('Missing config parameter(s)');}baseURLController = config.baseURLController;metricsModel = config.metricsModel;mediaPlayerModel = config.mediaPlayerModel;errHandler = config.errHandler;}function parseCues(ab){var cues=[];var cue=undefined;var cueTrack=undefined;var ebmlParser=(0,_streamingUtilsEBMLParser2['default'])(context).create({data:ab});ebmlParser.consumeTagAndSize(WebM.Segment.Cues);while(ebmlParser.moreData() && ebmlParser.consumeTagAndSize(WebM.Segment.Cues.CuePoint,true)) {cue = {};cue.CueTime = ebmlParser.parseTag(WebM.Segment.Cues.CuePoint.CueTime);cue.CueTracks = [];while(ebmlParser.moreData() && ebmlParser.consumeTag(WebM.Segment.Cues.CuePoint.CueTrackPositions,true)) {var cueTrackPositionSize=ebmlParser.getMatroskaCodedNum();var startPos=ebmlParser.getPos();cueTrack = {};cueTrack.Track = ebmlParser.parseTag(WebM.Segment.Cues.CuePoint.CueTrackPositions.CueTrack);if(cueTrack.Track === 0){throw new Error('Cue track cannot be 0');}cueTrack.ClusterPosition = ebmlParser.parseTag(WebM.Segment.Cues.CuePoint.CueTrackPositions.CueClusterPosition);cue.CueTracks.push(cueTrack); // we're not interested any other elements - skip remaining bytes
ebmlParser.setPos(startPos + cueTrackPositionSize);}if(cue.CueTracks.length === 0){throw new Error('Mandatory cuetrack not found');}cues.push(cue);}if(cues.length === 0){throw new Error('mandatory cuepoint not found');}return cues;}function parseSegments(data,segmentStart,segmentEnd,segmentDuration){var duration=undefined;var parsed=undefined;var segments=undefined;var segment=undefined;var i=undefined;var len=undefined;var start=undefined;var end=undefined;parsed = parseCues(data);segments = []; // we are assuming one cue track per cue point
// both duration and media range require the i + 1 segment
// the final segment has to use global segment parameters
for(i = 0,len = parsed.length;i < len;i += 1) {segment = new _voSegment2['default']();duration = 0;if(i < parsed.length - 1){duration = parsed[i + 1].CueTime - parsed[i].CueTime;}else {duration = segmentDuration - parsed[i].CueTime;} // note that we don't explicitly set segment.media as this will be
// computed when all BaseURLs are resolved later
segment.duration = duration;segment.startTime = parsed[i].CueTime;segment.timescale = 1000; // hardcoded for ms
start = parsed[i].CueTracks[0].ClusterPosition + segmentStart;if(i < parsed.length - 1){end = parsed[i + 1].CueTracks[0].ClusterPosition + segmentStart - 1;}else {end = segmentEnd - 1;}segment.mediaRange = start + '-' + end;segments.push(segment);}logger.debug('Parsed cues: ' + segments.length + ' cues.');return segments;}function parseEbmlHeader(data,media,theRange,callback){var ebmlParser=(0,_streamingUtilsEBMLParser2['default'])(context).create({data:data});var duration=undefined;var segments=undefined;var parts=theRange.split('-');var request=null;var info={url:media,range:{start:parseFloat(parts[0]),end:parseFloat(parts[1])},request:request};var segmentEnd=undefined;var segmentStart=undefined;logger.debug('Parse EBML header: ' + info.url); // skip over the header itself
ebmlParser.skipOverElement(WebM.EBML);ebmlParser.consumeTag(WebM.Segment); // segments start here
segmentEnd = ebmlParser.getMatroskaCodedNum();segmentEnd += ebmlParser.getPos();segmentStart = ebmlParser.getPos(); // skip over any top level elements to get to the segment info
while(ebmlParser.moreData() && !ebmlParser.consumeTagAndSize(WebM.Segment.Info,true)) {if(!(ebmlParser.skipOverElement(WebM.Segment.SeekHead,true) || ebmlParser.skipOverElement(WebM.Segment.Tracks,true) || ebmlParser.skipOverElement(WebM.Segment.Cues,true) || ebmlParser.skipOverElement(WebM.Void,true))){throw new Error('no valid top level element found');}} // we only need one thing in segment info, duration
while(duration === undefined) {var infoTag=ebmlParser.getMatroskaCodedNum(true);var infoElementSize=ebmlParser.getMatroskaCodedNum();switch(infoTag){case WebM.Segment.Info.Duration.tag:duration = ebmlParser[WebM.Segment.Info.Duration.parse](infoElementSize);break;default:ebmlParser.setPos(ebmlParser.getPos() + infoElementSize);break;}} // once we have what we need from segment info, we jump right to the
// cues
request = getFragmentRequest(info);var onload=function onload(response){segments = parseSegments(response,segmentStart,segmentEnd,duration);callback(segments);};var onloadend=function onloadend(){logger.error('Download Error: Cues ' + info.url);callback(null);};httpLoader.load({request:request,success:onload,error:onloadend});logger.debug('Perform cues load: ' + info.url + ' bytes=' + info.range.start + '-' + info.range.end);}function checkSetConfigCall(){if(!baseURLController || !baseURLController.hasOwnProperty('resolve')){throw new Error('setConfig function has to be called previously');}}function loadInitialization(representation,loadingInfo){checkSetConfigCall();var request=null;var baseUrl=baseURLController.resolve(representation.path);var media=baseUrl?baseUrl.url:undefined;var initRange=representation.range.split('-');var info=loadingInfo || {range:{start:parseFloat(initRange[0]),end:parseFloat(initRange[1])},request:request,url:media,init:true};logger.info('Start loading initialization.');request = getFragmentRequest(info);var onload=function onload(){ // note that we don't explicitly set rep.initialization as this
// will be computed when all BaseURLs are resolved later
eventBus.trigger(_coreEventsEvents2['default'].INITIALIZATION_LOADED,{representation:representation});};var onloadend=function onloadend(){eventBus.trigger(_coreEventsEvents2['default'].INITIALIZATION_LOADED,{representation:representation});};httpLoader.load({request:request,success:onload,error:onloadend});logger.debug('Perform init load: ' + info.url);}function loadSegments(representation,type,theRange,callback){checkSetConfigCall();var request=null;var baseUrl=baseURLController.resolve(representation.path);var media=baseUrl?baseUrl.url:undefined;var bytesToLoad=8192;var info={bytesLoaded:0,bytesToLoad:bytesToLoad,range:{start:0,end:bytesToLoad},request:request,url:media,init:false};callback = !callback?onLoaded:callback;request = getFragmentRequest(info); // first load the header, but preserve the manifest range so we can
// load the cues after parsing the header
// NOTE: we expect segment info to appear in the first 8192 bytes
logger.debug('Parsing ebml header');var onload=function onload(response){parseEbmlHeader(response,media,theRange,function(segments){callback(segments,representation,type);});};var onloadend=function onloadend(){callback(null,representation,type);};httpLoader.load({request:request,success:onload,error:onloadend});}function onLoaded(segments,representation,type){if(segments){eventBus.trigger(_coreEventsEvents2['default'].SEGMENTS_LOADED,{segments:segments,representation:representation,mediaType:type});}else {eventBus.trigger(_coreEventsEvents2['default'].SEGMENTS_LOADED,{segments:null,representation:representation,mediaType:type,error:new _streamingVoDashJSError2['default'](_coreErrorsErrors2['default'].SEGMENT_BASE_LOADER_ERROR_CODE,_coreErrorsErrors2['default'].SEGMENT_BASE_LOADER_ERROR_MESSAGE)});}}function getFragmentRequest(info){var request=new _streamingVoFragmentRequest2['default']();request.type = info.init?_streamingVoMetricsHTTPRequest.HTTPRequest.INIT_SEGMENT_TYPE:_streamingVoMetricsHTTPRequest.HTTPRequest.MEDIA_SEGMENT_TYPE;request.url = info.url;request.range = info.range.start + '-' + info.range.end;return request;}function reset(){errHandler = null;requestModifier = null;}instance = {setConfig:setConfig,initialize:initialize,loadInitialization:loadInitialization,loadSegments:loadSegments,reset:reset};setup();return instance;}WebmSegmentBaseLoader.__dashjs_factory_name = 'WebmSegmentBaseLoader';exports['default'] = _coreFactoryMaker2['default'].getSingletonFactory(WebmSegmentBaseLoader);module.exports = exports['default'];
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