buymymojo.net/node_modules/@videojs/http-streaming/src/master-playlist-controller.js
2021-07-02 19:29:34 +10:00

1944 lines
63 KiB
JavaScript

/**
* @file master-playlist-controller.js
*/
import window from 'global/window';
import PlaylistLoader from './playlist-loader';
import DashPlaylistLoader from './dash-playlist-loader';
import { isEnabled, isLowestEnabledRendition } from './playlist.js';
import SegmentLoader from './segment-loader';
import SourceUpdater from './source-updater';
import VTTSegmentLoader from './vtt-segment-loader';
import * as Ranges from './ranges';
import videojs from 'video.js';
import { updateAdCues } from './ad-cue-tags';
import SyncController from './sync-controller';
import TimelineChangeController from './timeline-change-controller';
import Decrypter from 'worker!./decrypter-worker.js';
import Config from './config';
import {
parseCodecs,
browserSupportsCodec,
muxerSupportsCodec,
DEFAULT_AUDIO_CODEC,
DEFAULT_VIDEO_CODEC
} from '@videojs/vhs-utils/es/codecs.js';
import { codecsForPlaylist, unwrapCodecList, codecCount } from './util/codecs.js';
import { createMediaTypes, setupMediaGroups } from './media-groups';
import logger from './util/logger';
const ABORT_EARLY_BLACKLIST_SECONDS = 60 * 2;
let Vhs;
// SegmentLoader stats that need to have each loader's
// values summed to calculate the final value
const loaderStats = [
'mediaRequests',
'mediaRequestsAborted',
'mediaRequestsTimedout',
'mediaRequestsErrored',
'mediaTransferDuration',
'mediaBytesTransferred',
'mediaAppends'
];
const sumLoaderStat = function(stat) {
return this.audioSegmentLoader_[stat] +
this.mainSegmentLoader_[stat];
};
const shouldSwitchToMedia = function({
currentPlaylist,
nextPlaylist,
forwardBuffer,
bufferLowWaterLine,
bufferHighWaterLine,
duration,
experimentalBufferBasedABR,
log
}) {
// we have no other playlist to switch to
if (!nextPlaylist) {
videojs.log.warn('We received no playlist to switch to. Please check your stream.');
return false;
}
const sharedLogLine = `allowing switch ${currentPlaylist && currentPlaylist.id || 'null'} -> ${nextPlaylist.id}`;
// If the playlist is live, then we want to not take low water line into account.
// This is because in LIVE, the player plays 3 segments from the end of the
// playlist, and if `BUFFER_LOW_WATER_LINE` is greater than the duration availble
// in those segments, a viewer will never experience a rendition upswitch.
if (!currentPlaylist || !currentPlaylist.endList) {
log(`${sharedLogLine} as current playlist ` + (!currentPlaylist ? 'is not set' : 'is live'));
return true;
}
// no need to switch playlist is the same
if (nextPlaylist.id === currentPlaylist.id) {
return false;
}
const maxBufferLowWaterLine = experimentalBufferBasedABR ?
Config.EXPERIMENTAL_MAX_BUFFER_LOW_WATER_LINE : Config.MAX_BUFFER_LOW_WATER_LINE;
// For the same reason as LIVE, we ignore the low water line when the VOD
// duration is below the max potential low water line
if (duration < maxBufferLowWaterLine) {
log(`${sharedLogLine} as duration < max low water line (${duration} < ${maxBufferLowWaterLine})`);
return true;
}
const nextBandwidth = nextPlaylist.attributes.BANDWIDTH;
const currBandwidth = currentPlaylist.attributes.BANDWIDTH;
// when switching down, if our buffer is lower than the high water line,
// we can switch down
if (nextBandwidth < currBandwidth && (!experimentalBufferBasedABR || forwardBuffer < bufferHighWaterLine)) {
let logLine = `${sharedLogLine} as next bandwidth < current bandwidth (${nextBandwidth} < ${currBandwidth})`;
if (experimentalBufferBasedABR) {
logLine += ` and forwardBuffer < bufferHighWaterLine (${forwardBuffer} < ${bufferHighWaterLine})`;
}
log(logLine);
return true;
}
// and if our buffer is higher than the low water line,
// we can switch up
if ((!experimentalBufferBasedABR || nextBandwidth > currBandwidth) && forwardBuffer >= bufferLowWaterLine) {
let logLine = `${sharedLogLine} as forwardBuffer >= bufferLowWaterLine (${forwardBuffer} >= ${bufferLowWaterLine})`;
if (experimentalBufferBasedABR) {
logLine += ` and next bandwidth > current bandwidth (${nextBandwidth} > ${currBandwidth})`;
}
log(logLine);
return true;
}
log(`not ${sharedLogLine} as no switching criteria met`);
return false;
};
/**
* the master playlist controller controller all interactons
* between playlists and segmentloaders. At this time this mainly
* involves a master playlist and a series of audio playlists
* if they are available
*
* @class MasterPlaylistController
* @extends videojs.EventTarget
*/
export class MasterPlaylistController extends videojs.EventTarget {
constructor(options) {
super();
const {
src,
handleManifestRedirects,
withCredentials,
tech,
bandwidth,
externVhs,
useCueTags,
blacklistDuration,
enableLowInitialPlaylist,
sourceType,
cacheEncryptionKeys,
experimentalBufferBasedABR
} = options;
if (!src) {
throw new Error('A non-empty playlist URL or JSON manifest string is required');
}
let { maxPlaylistRetries } = options;
if (maxPlaylistRetries === null || typeof maxPlaylistRetries === 'undefined') {
maxPlaylistRetries = Infinity;
}
Vhs = externVhs;
this.experimentalBufferBasedABR = Boolean(experimentalBufferBasedABR);
this.withCredentials = withCredentials;
this.tech_ = tech;
this.vhs_ = tech.vhs;
this.sourceType_ = sourceType;
this.useCueTags_ = useCueTags;
this.blacklistDuration = blacklistDuration;
this.maxPlaylistRetries = maxPlaylistRetries;
this.enableLowInitialPlaylist = enableLowInitialPlaylist;
if (this.useCueTags_) {
this.cueTagsTrack_ = this.tech_.addTextTrack(
'metadata',
'ad-cues'
);
this.cueTagsTrack_.inBandMetadataTrackDispatchType = '';
}
this.requestOptions_ = {
withCredentials,
handleManifestRedirects,
maxPlaylistRetries,
timeout: null
};
this.on('error', this.pauseLoading);
this.mediaTypes_ = createMediaTypes();
this.mediaSource = new window.MediaSource();
this.handleDurationChange_ = this.handleDurationChange_.bind(this);
this.handleSourceOpen_ = this.handleSourceOpen_.bind(this);
this.handleSourceEnded_ = this.handleSourceEnded_.bind(this);
this.mediaSource.addEventListener('durationchange', this.handleDurationChange_);
// load the media source into the player
this.mediaSource.addEventListener('sourceopen', this.handleSourceOpen_);
this.mediaSource.addEventListener('sourceended', this.handleSourceEnded_);
// we don't have to handle sourceclose since dispose will handle termination of
// everything, and the MediaSource should not be detached without a proper disposal
this.seekable_ = videojs.createTimeRanges();
this.hasPlayed_ = false;
this.syncController_ = new SyncController(options);
this.segmentMetadataTrack_ = tech.addRemoteTextTrack({
kind: 'metadata',
label: 'segment-metadata'
}, false).track;
this.decrypter_ = new Decrypter();
this.sourceUpdater_ = new SourceUpdater(this.mediaSource);
this.inbandTextTracks_ = {};
this.timelineChangeController_ = new TimelineChangeController();
const segmentLoaderSettings = {
vhs: this.vhs_,
parse708captions: options.parse708captions,
mediaSource: this.mediaSource,
currentTime: this.tech_.currentTime.bind(this.tech_),
seekable: () => this.seekable(),
seeking: () => this.tech_.seeking(),
duration: () => this.duration(),
hasPlayed: () => this.hasPlayed_,
goalBufferLength: () => this.goalBufferLength(),
bandwidth,
syncController: this.syncController_,
decrypter: this.decrypter_,
sourceType: this.sourceType_,
inbandTextTracks: this.inbandTextTracks_,
cacheEncryptionKeys,
sourceUpdater: this.sourceUpdater_,
timelineChangeController: this.timelineChangeController_
};
// The source type check not only determines whether a special DASH playlist loader
// should be used, but also covers the case where the provided src is a vhs-json
// manifest object (instead of a URL). In the case of vhs-json, the default
// PlaylistLoader should be used.
this.masterPlaylistLoader_ = this.sourceType_ === 'dash' ?
new DashPlaylistLoader(src, this.vhs_, this.requestOptions_) :
new PlaylistLoader(src, this.vhs_, this.requestOptions_);
this.setupMasterPlaylistLoaderListeners_();
// setup segment loaders
// combined audio/video or just video when alternate audio track is selected
this.mainSegmentLoader_ =
new SegmentLoader(videojs.mergeOptions(segmentLoaderSettings, {
segmentMetadataTrack: this.segmentMetadataTrack_,
loaderType: 'main'
}), options);
// alternate audio track
this.audioSegmentLoader_ =
new SegmentLoader(videojs.mergeOptions(segmentLoaderSettings, {
loaderType: 'audio'
}), options);
this.subtitleSegmentLoader_ =
new VTTSegmentLoader(videojs.mergeOptions(segmentLoaderSettings, {
loaderType: 'vtt',
featuresNativeTextTracks: this.tech_.featuresNativeTextTracks
}), options);
this.setupSegmentLoaderListeners_();
if (this.experimentalBufferBasedABR) {
this.masterPlaylistLoader_.one('loadedplaylist', () => this.startABRTimer_());
this.tech_.on('pause', () => this.stopABRTimer_());
this.tech_.on('play', () => this.startABRTimer_());
}
// Create SegmentLoader stat-getters
// mediaRequests_
// mediaRequestsAborted_
// mediaRequestsTimedout_
// mediaRequestsErrored_
// mediaTransferDuration_
// mediaBytesTransferred_
// mediaAppends_
loaderStats.forEach((stat) => {
this[stat + '_'] = sumLoaderStat.bind(this, stat);
});
this.logger_ = logger('MPC');
this.triggeredFmp4Usage = false;
if (this.tech_.preload() === 'none') {
this.loadOnPlay_ = () => {
this.loadOnPlay_ = null;
this.masterPlaylistLoader_.load();
};
this.tech_.one('play', this.loadOnPlay_);
} else {
this.masterPlaylistLoader_.load();
}
this.timeToLoadedData__ = -1;
this.mainAppendsToLoadedData__ = -1;
this.audioAppendsToLoadedData__ = -1;
const event = this.tech_.preload() === 'none' ? 'play' : 'loadstart';
// start the first frame timer on loadstart or play (for preload none)
this.tech_.one(event, () => {
const timeToLoadedDataStart = Date.now();
this.tech_.one('loadeddata', () => {
this.timeToLoadedData__ = Date.now() - timeToLoadedDataStart;
this.mainAppendsToLoadedData__ = this.mainSegmentLoader_.mediaAppends;
this.audioAppendsToLoadedData__ = this.audioSegmentLoader_.mediaAppends;
});
});
}
mainAppendsToLoadedData_() {
return this.mainAppendsToLoadedData__;
}
audioAppendsToLoadedData_() {
return this.audioAppendsToLoadedData__;
}
appendsToLoadedData_() {
const main = this.mainAppendsToLoadedData_();
const audio = this.audioAppendsToLoadedData_();
if (main === -1 || audio === -1) {
return -1;
}
return main + audio;
}
timeToLoadedData_() {
return this.timeToLoadedData__;
}
/**
* Run selectPlaylist and switch to the new playlist if we should
*
* @private
*
*/
checkABR_() {
const nextPlaylist = this.selectPlaylist();
if (this.shouldSwitchToMedia_(nextPlaylist)) {
this.switchMedia_(nextPlaylist, 'abr');
}
}
switchMedia_(playlist, cause, delay) {
const oldMedia = this.media();
const oldId = oldMedia && (oldMedia.id || oldMedia.uri);
const newId = playlist.id || playlist.uri;
if (oldId && oldId !== newId) {
this.logger_(`switch media ${oldId} -> ${newId} from ${cause}`);
this.tech_.trigger({type: 'usage', name: `vhs-rendition-change-${cause}`});
}
this.masterPlaylistLoader_.media(playlist, delay);
}
/**
* Start a timer that periodically calls checkABR_
*
* @private
*/
startABRTimer_() {
this.stopABRTimer_();
this.abrTimer_ = window.setInterval(() => this.checkABR_(), 250);
}
/**
* Stop the timer that periodically calls checkABR_
*
* @private
*/
stopABRTimer_() {
// if we're scrubbing, we don't need to pause.
// This getter will be added to Video.js in version 7.11.
if (this.tech_.scrubbing && this.tech_.scrubbing()) {
return;
}
window.clearInterval(this.abrTimer_);
this.abrTimer_ = null;
}
/**
* Get a list of playlists for the currently selected audio playlist
*
* @return {Array} the array of audio playlists
*/
getAudioTrackPlaylists_() {
const master = this.master();
// if we don't have any audio groups then we can only
// assume that the audio tracks are contained in masters
// playlist array, use that or an empty array.
if (!master || !master.mediaGroups || !master.mediaGroups.AUDIO) {
return master && master.playlists || [];
}
const AUDIO = master.mediaGroups.AUDIO;
const groupKeys = Object.keys(AUDIO);
let track;
// get the current active track
if (Object.keys(this.mediaTypes_.AUDIO.groups).length) {
track = this.mediaTypes_.AUDIO.activeTrack();
// or get the default track from master if mediaTypes_ isn't setup yet
} else {
// default group is `main` or just the first group.
const defaultGroup = AUDIO.main || groupKeys.length && AUDIO[groupKeys[0]];
for (const label in defaultGroup) {
if (defaultGroup[label].default) {
track = {label};
break;
}
}
}
// no active track no playlists.
if (!track) {
return [];
}
const playlists = [];
// get all of the playlists that are possible for the
// active track.
for (const group in AUDIO) {
if (AUDIO[group][track.label]) {
const properties = AUDIO[group][track.label];
if (properties.playlists) {
playlists.push.apply(playlists, properties.playlists);
} else {
playlists.push(properties);
}
}
}
return playlists;
}
/**
* Register event handlers on the master playlist loader. A helper
* function for construction time.
*
* @private
*/
setupMasterPlaylistLoaderListeners_() {
this.masterPlaylistLoader_.on('loadedmetadata', () => {
const media = this.masterPlaylistLoader_.media();
const requestTimeout = (media.targetDuration * 1.5) * 1000;
// If we don't have any more available playlists, we don't want to
// timeout the request.
if (isLowestEnabledRendition(this.masterPlaylistLoader_.master, this.masterPlaylistLoader_.media())) {
this.requestOptions_.timeout = 0;
} else {
this.requestOptions_.timeout = requestTimeout;
}
// if this isn't a live video and preload permits, start
// downloading segments
if (media.endList && this.tech_.preload() !== 'none') {
this.mainSegmentLoader_.playlist(media, this.requestOptions_);
this.mainSegmentLoader_.load();
}
setupMediaGroups({
sourceType: this.sourceType_,
segmentLoaders: {
AUDIO: this.audioSegmentLoader_,
SUBTITLES: this.subtitleSegmentLoader_,
main: this.mainSegmentLoader_
},
tech: this.tech_,
requestOptions: this.requestOptions_,
masterPlaylistLoader: this.masterPlaylistLoader_,
vhs: this.vhs_,
master: this.master(),
mediaTypes: this.mediaTypes_,
blacklistCurrentPlaylist: this.blacklistCurrentPlaylist.bind(this)
});
this.triggerPresenceUsage_(this.master(), media);
this.setupFirstPlay();
if (!this.mediaTypes_.AUDIO.activePlaylistLoader ||
this.mediaTypes_.AUDIO.activePlaylistLoader.media()) {
this.trigger('selectedinitialmedia');
} else {
// We must wait for the active audio playlist loader to
// finish setting up before triggering this event so the
// representations API and EME setup is correct
this.mediaTypes_.AUDIO.activePlaylistLoader.one('loadedmetadata', () => {
this.trigger('selectedinitialmedia');
});
}
});
this.masterPlaylistLoader_.on('loadedplaylist', () => {
if (this.loadOnPlay_) {
this.tech_.off('play', this.loadOnPlay_);
}
let updatedPlaylist = this.masterPlaylistLoader_.media();
if (!updatedPlaylist) {
// exclude any variants that are not supported by the browser before selecting
// an initial media as the playlist selectors do not consider browser support
this.excludeUnsupportedVariants_();
let selectedMedia;
if (this.enableLowInitialPlaylist) {
selectedMedia = this.selectInitialPlaylist();
}
if (!selectedMedia) {
selectedMedia = this.selectPlaylist();
}
if (!selectedMedia || !this.shouldSwitchToMedia_(selectedMedia)) {
return;
}
this.initialMedia_ = selectedMedia;
this.switchMedia_(this.initialMedia_, 'initial');
// Under the standard case where a source URL is provided, loadedplaylist will
// fire again since the playlist will be requested. In the case of vhs-json
// (where the manifest object is provided as the source), when the media
// playlist's `segments` list is already available, a media playlist won't be
// requested, and loadedplaylist won't fire again, so the playlist handler must be
// called on its own here.
const haveJsonSource = this.sourceType_ === 'vhs-json' && this.initialMedia_.segments;
if (!haveJsonSource) {
return;
}
updatedPlaylist = this.initialMedia_;
}
this.handleUpdatedMediaPlaylist(updatedPlaylist);
});
this.masterPlaylistLoader_.on('error', () => {
this.blacklistCurrentPlaylist(this.masterPlaylistLoader_.error);
});
this.masterPlaylistLoader_.on('mediachanging', () => {
this.mainSegmentLoader_.abort();
this.mainSegmentLoader_.pause();
});
this.masterPlaylistLoader_.on('mediachange', () => {
const media = this.masterPlaylistLoader_.media();
const requestTimeout = (media.targetDuration * 1.5) * 1000;
// If we don't have any more available playlists, we don't want to
// timeout the request.
if (isLowestEnabledRendition(this.masterPlaylistLoader_.master, this.masterPlaylistLoader_.media())) {
this.requestOptions_.timeout = 0;
} else {
this.requestOptions_.timeout = requestTimeout;
}
// TODO: Create a new event on the PlaylistLoader that signals
// that the segments have changed in some way and use that to
// update the SegmentLoader instead of doing it twice here and
// on `loadedplaylist`
this.mainSegmentLoader_.playlist(media, this.requestOptions_);
this.mainSegmentLoader_.load();
this.tech_.trigger({
type: 'mediachange',
bubbles: true
});
});
this.masterPlaylistLoader_.on('playlistunchanged', () => {
const updatedPlaylist = this.masterPlaylistLoader_.media();
// ignore unchanged playlists that have already been
// excluded for not-changing. We likely just have a really slowly updating
// playlist.
if (updatedPlaylist.lastExcludeReason_ === 'playlist-unchanged') {
return;
}
const playlistOutdated = this.stuckAtPlaylistEnd_(updatedPlaylist);
if (playlistOutdated) {
// Playlist has stopped updating and we're stuck at its end. Try to
// blacklist it and switch to another playlist in the hope that that
// one is updating (and give the player a chance to re-adjust to the
// safe live point).
this.blacklistCurrentPlaylist({
message: 'Playlist no longer updating.',
reason: 'playlist-unchanged'
});
// useful for monitoring QoS
this.tech_.trigger('playliststuck');
}
});
this.masterPlaylistLoader_.on('renditiondisabled', () => {
this.tech_.trigger({type: 'usage', name: 'vhs-rendition-disabled'});
this.tech_.trigger({type: 'usage', name: 'hls-rendition-disabled'});
});
this.masterPlaylistLoader_.on('renditionenabled', () => {
this.tech_.trigger({type: 'usage', name: 'vhs-rendition-enabled'});
this.tech_.trigger({type: 'usage', name: 'hls-rendition-enabled'});
});
}
/**
* Given an updated media playlist (whether it was loaded for the first time, or
* refreshed for live playlists), update any relevant properties and state to reflect
* changes in the media that should be accounted for (e.g., cues and duration).
*
* @param {Object} updatedPlaylist the updated media playlist object
*
* @private
*/
handleUpdatedMediaPlaylist(updatedPlaylist) {
if (this.useCueTags_) {
this.updateAdCues_(updatedPlaylist);
}
// TODO: Create a new event on the PlaylistLoader that signals
// that the segments have changed in some way and use that to
// update the SegmentLoader instead of doing it twice here and
// on `mediachange`
this.mainSegmentLoader_.playlist(updatedPlaylist, this.requestOptions_);
this.updateDuration(!updatedPlaylist.endList);
// If the player isn't paused, ensure that the segment loader is running,
// as it is possible that it was temporarily stopped while waiting for
// a playlist (e.g., in case the playlist errored and we re-requested it).
if (!this.tech_.paused()) {
this.mainSegmentLoader_.load();
if (this.audioSegmentLoader_) {
this.audioSegmentLoader_.load();
}
}
}
/**
* A helper function for triggerring presence usage events once per source
*
* @private
*/
triggerPresenceUsage_(master, media) {
const mediaGroups = master.mediaGroups || {};
let defaultDemuxed = true;
const audioGroupKeys = Object.keys(mediaGroups.AUDIO);
for (const mediaGroup in mediaGroups.AUDIO) {
for (const label in mediaGroups.AUDIO[mediaGroup]) {
const properties = mediaGroups.AUDIO[mediaGroup][label];
if (!properties.uri) {
defaultDemuxed = false;
}
}
}
if (defaultDemuxed) {
this.tech_.trigger({type: 'usage', name: 'vhs-demuxed'});
this.tech_.trigger({type: 'usage', name: 'hls-demuxed'});
}
if (Object.keys(mediaGroups.SUBTITLES).length) {
this.tech_.trigger({type: 'usage', name: 'vhs-webvtt'});
this.tech_.trigger({type: 'usage', name: 'hls-webvtt'});
}
if (Vhs.Playlist.isAes(media)) {
this.tech_.trigger({type: 'usage', name: 'vhs-aes'});
this.tech_.trigger({type: 'usage', name: 'hls-aes'});
}
if (audioGroupKeys.length &&
Object.keys(mediaGroups.AUDIO[audioGroupKeys[0]]).length > 1) {
this.tech_.trigger({type: 'usage', name: 'vhs-alternate-audio'});
this.tech_.trigger({type: 'usage', name: 'hls-alternate-audio'});
}
if (this.useCueTags_) {
this.tech_.trigger({type: 'usage', name: 'vhs-playlist-cue-tags'});
this.tech_.trigger({type: 'usage', name: 'hls-playlist-cue-tags'});
}
}
shouldSwitchToMedia_(nextPlaylist) {
const currentPlaylist = this.masterPlaylistLoader_.media();
const buffered = this.tech_.buffered();
const forwardBuffer = buffered.length ?
buffered.end(buffered.length - 1) - this.tech_.currentTime() : 0;
const bufferLowWaterLine = this.bufferLowWaterLine();
const bufferHighWaterLine = this.bufferHighWaterLine();
return shouldSwitchToMedia({
currentPlaylist,
nextPlaylist,
forwardBuffer,
bufferLowWaterLine,
bufferHighWaterLine,
duration: this.duration(),
experimentalBufferBasedABR: this.experimentalBufferBasedABR,
log: this.logger_
});
}
/**
* Register event handlers on the segment loaders. A helper function
* for construction time.
*
* @private
*/
setupSegmentLoaderListeners_() {
if (!this.experimentalBufferBasedABR) {
this.mainSegmentLoader_.on('bandwidthupdate', () => {
const nextPlaylist = this.selectPlaylist();
if (this.shouldSwitchToMedia_(nextPlaylist)) {
this.switchMedia_(nextPlaylist, 'bandwidthupdate');
}
this.tech_.trigger('bandwidthupdate');
});
this.mainSegmentLoader_.on('progress', () => {
this.trigger('progress');
});
}
this.mainSegmentLoader_.on('error', () => {
this.blacklistCurrentPlaylist(this.mainSegmentLoader_.error());
});
this.mainSegmentLoader_.on('appenderror', () => {
this.error = this.mainSegmentLoader_.error_;
this.trigger('error');
});
this.mainSegmentLoader_.on('syncinfoupdate', () => {
this.onSyncInfoUpdate_();
});
this.mainSegmentLoader_.on('timestampoffset', () => {
this.tech_.trigger({type: 'usage', name: 'vhs-timestamp-offset'});
this.tech_.trigger({type: 'usage', name: 'hls-timestamp-offset'});
});
this.audioSegmentLoader_.on('syncinfoupdate', () => {
this.onSyncInfoUpdate_();
});
this.audioSegmentLoader_.on('appenderror', () => {
this.error = this.audioSegmentLoader_.error_;
this.trigger('error');
});
this.mainSegmentLoader_.on('ended', () => {
this.logger_('main segment loader ended');
this.onEndOfStream();
});
this.mainSegmentLoader_.on('earlyabort', (event) => {
// never try to early abort with the new ABR algorithm
if (this.experimentalBufferBasedABR) {
return;
}
this.delegateLoaders_('all', ['abort']);
this.blacklistCurrentPlaylist({
message: 'Aborted early because there isn\'t enough bandwidth to complete the ' +
'request without rebuffering.'
}, ABORT_EARLY_BLACKLIST_SECONDS);
});
const updateCodecs = () => {
if (!this.sourceUpdater_.hasCreatedSourceBuffers()) {
return this.tryToCreateSourceBuffers_();
}
const codecs = this.getCodecsOrExclude_();
// no codecs means that the playlist was excluded
if (!codecs) {
return;
}
this.sourceUpdater_.addOrChangeSourceBuffers(codecs);
};
this.mainSegmentLoader_.on('trackinfo', updateCodecs);
this.audioSegmentLoader_.on('trackinfo', updateCodecs);
this.mainSegmentLoader_.on('fmp4', () => {
if (!this.triggeredFmp4Usage) {
this.tech_.trigger({type: 'usage', name: 'vhs-fmp4'});
this.tech_.trigger({type: 'usage', name: 'hls-fmp4'});
this.triggeredFmp4Usage = true;
}
});
this.audioSegmentLoader_.on('fmp4', () => {
if (!this.triggeredFmp4Usage) {
this.tech_.trigger({type: 'usage', name: 'vhs-fmp4'});
this.tech_.trigger({type: 'usage', name: 'hls-fmp4'});
this.triggeredFmp4Usage = true;
}
});
this.audioSegmentLoader_.on('ended', () => {
this.logger_('audioSegmentLoader ended');
this.onEndOfStream();
});
}
mediaSecondsLoaded_() {
return Math.max(this.audioSegmentLoader_.mediaSecondsLoaded +
this.mainSegmentLoader_.mediaSecondsLoaded);
}
/**
* Call load on our SegmentLoaders
*/
load() {
this.mainSegmentLoader_.load();
if (this.mediaTypes_.AUDIO.activePlaylistLoader) {
this.audioSegmentLoader_.load();
}
if (this.mediaTypes_.SUBTITLES.activePlaylistLoader) {
this.subtitleSegmentLoader_.load();
}
}
/**
* Re-tune playback quality level for the current player
* conditions without performing destructive actions, like
* removing already buffered content
*
* @private
* @deprecated
*/
smoothQualityChange_(media = this.selectPlaylist()) {
this.fastQualityChange_(media);
}
/**
* Re-tune playback quality level for the current player
* conditions. This method will perform destructive actions like removing
* already buffered content in order to readjust the currently active
* playlist quickly. This is good for manual quality changes
*
* @private
*/
fastQualityChange_(media = this.selectPlaylist()) {
if (media === this.masterPlaylistLoader_.media()) {
this.logger_('skipping fastQualityChange because new media is same as old');
return;
}
this.switchMedia_(media, 'fast-quality');
// Delete all buffered data to allow an immediate quality switch, then seek to give
// the browser a kick to remove any cached frames from the previous rendtion (.04 seconds
// ahead is roughly the minimum that will accomplish this across a variety of content
// in IE and Edge, but seeking in place is sufficient on all other browsers)
// Edge/IE bug: https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/14600375/
// Chrome bug: https://bugs.chromium.org/p/chromium/issues/detail?id=651904
this.mainSegmentLoader_.resetEverything(() => {
// Since this is not a typical seek, we avoid the seekTo method which can cause segments
// from the previously enabled rendition to load before the new playlist has finished loading
if (videojs.browser.IE_VERSION || videojs.browser.IS_EDGE) {
this.tech_.setCurrentTime(this.tech_.currentTime() + 0.04);
} else {
this.tech_.setCurrentTime(this.tech_.currentTime());
}
});
// don't need to reset audio as it is reset when media changes
}
/**
* Begin playback.
*/
play() {
if (this.setupFirstPlay()) {
return;
}
if (this.tech_.ended()) {
this.tech_.setCurrentTime(0);
}
if (this.hasPlayed_) {
this.load();
}
const seekable = this.tech_.seekable();
// if the viewer has paused and we fell out of the live window,
// seek forward to the live point
if (this.tech_.duration() === Infinity) {
if (this.tech_.currentTime() < seekable.start(0)) {
return this.tech_.setCurrentTime(seekable.end(seekable.length - 1));
}
}
}
/**
* Seek to the latest media position if this is a live video and the
* player and video are loaded and initialized.
*/
setupFirstPlay() {
const media = this.masterPlaylistLoader_.media();
// Check that everything is ready to begin buffering for the first call to play
// If 1) there is no active media
// 2) the player is paused
// 3) the first play has already been setup
// then exit early
if (!media || this.tech_.paused() || this.hasPlayed_) {
return false;
}
// when the video is a live stream
if (!media.endList) {
const seekable = this.seekable();
if (!seekable.length) {
// without a seekable range, the player cannot seek to begin buffering at the live
// point
return false;
}
if (videojs.browser.IE_VERSION &&
this.tech_.readyState() === 0) {
// IE11 throws an InvalidStateError if you try to set currentTime while the
// readyState is 0, so it must be delayed until the tech fires loadedmetadata.
this.tech_.one('loadedmetadata', () => {
this.trigger('firstplay');
this.tech_.setCurrentTime(seekable.end(0));
this.hasPlayed_ = true;
});
return false;
}
// trigger firstplay to inform the source handler to ignore the next seek event
this.trigger('firstplay');
// seek to the live point
this.tech_.setCurrentTime(seekable.end(0));
}
this.hasPlayed_ = true;
// we can begin loading now that everything is ready
this.load();
return true;
}
/**
* handle the sourceopen event on the MediaSource
*
* @private
*/
handleSourceOpen_() {
// Only attempt to create the source buffer if none already exist.
// handleSourceOpen is also called when we are "re-opening" a source buffer
// after `endOfStream` has been called (in response to a seek for instance)
this.tryToCreateSourceBuffers_();
// if autoplay is enabled, begin playback. This is duplicative of
// code in video.js but is required because play() must be invoked
// *after* the media source has opened.
if (this.tech_.autoplay()) {
const playPromise = this.tech_.play();
// Catch/silence error when a pause interrupts a play request
// on browsers which return a promise
if (typeof playPromise !== 'undefined' && typeof playPromise.then === 'function') {
playPromise.then(null, (e) => {});
}
}
this.trigger('sourceopen');
}
/**
* handle the sourceended event on the MediaSource
*
* @private
*/
handleSourceEnded_() {
if (!this.inbandTextTracks_.metadataTrack_) {
return;
}
const cues = this.inbandTextTracks_.metadataTrack_.cues;
if (!cues || !cues.length) {
return;
}
const duration = this.duration();
cues[cues.length - 1].endTime = isNaN(duration) || Math.abs(duration) === Infinity ?
Number.MAX_VALUE : duration;
}
/**
* handle the durationchange event on the MediaSource
*
* @private
*/
handleDurationChange_() {
this.tech_.trigger('durationchange');
}
/**
* Calls endOfStream on the media source when all active stream types have called
* endOfStream
*
* @param {string} streamType
* Stream type of the segment loader that called endOfStream
* @private
*/
onEndOfStream() {
let isEndOfStream = this.mainSegmentLoader_.ended_;
if (this.mediaTypes_.AUDIO.activePlaylistLoader) {
// if the audio playlist loader exists, then alternate audio is active
if (!this.mainSegmentLoader_.currentMediaInfo_ ||
this.mainSegmentLoader_.currentMediaInfo_.hasVideo) {
// if we do not know if the main segment loader contains video yet or if we
// definitively know the main segment loader contains video, then we need to wait
// for both main and audio segment loaders to call endOfStream
isEndOfStream = isEndOfStream && this.audioSegmentLoader_.ended_;
} else {
// otherwise just rely on the audio loader
isEndOfStream = this.audioSegmentLoader_.ended_;
}
}
if (!isEndOfStream) {
return;
}
this.stopABRTimer_();
this.sourceUpdater_.endOfStream();
}
/**
* Check if a playlist has stopped being updated
*
* @param {Object} playlist the media playlist object
* @return {boolean} whether the playlist has stopped being updated or not
*/
stuckAtPlaylistEnd_(playlist) {
const seekable = this.seekable();
if (!seekable.length) {
// playlist doesn't have enough information to determine whether we are stuck
return false;
}
const expired =
this.syncController_.getExpiredTime(playlist, this.duration());
if (expired === null) {
return false;
}
// does not use the safe live end to calculate playlist end, since we
// don't want to say we are stuck while there is still content
const absolutePlaylistEnd = Vhs.Playlist.playlistEnd(playlist, expired);
const currentTime = this.tech_.currentTime();
const buffered = this.tech_.buffered();
if (!buffered.length) {
// return true if the playhead reached the absolute end of the playlist
return absolutePlaylistEnd - currentTime <= Ranges.SAFE_TIME_DELTA;
}
const bufferedEnd = buffered.end(buffered.length - 1);
// return true if there is too little buffer left and buffer has reached absolute
// end of playlist
return bufferedEnd - currentTime <= Ranges.SAFE_TIME_DELTA &&
absolutePlaylistEnd - bufferedEnd <= Ranges.SAFE_TIME_DELTA;
}
/**
* Blacklists a playlist when an error occurs for a set amount of time
* making it unavailable for selection by the rendition selection algorithm
* and then forces a new playlist (rendition) selection.
*
* @param {Object=} error an optional error that may include the playlist
* to blacklist
* @param {number=} blacklistDuration an optional number of seconds to blacklist the
* playlist
*/
blacklistCurrentPlaylist(error = {}, blacklistDuration) {
// If the `error` was generated by the playlist loader, it will contain
// the playlist we were trying to load (but failed) and that should be
// blacklisted instead of the currently selected playlist which is likely
// out-of-date in this scenario
const currentPlaylist = error.playlist || this.masterPlaylistLoader_.media();
blacklistDuration = blacklistDuration ||
error.blacklistDuration ||
this.blacklistDuration;
// If there is no current playlist, then an error occurred while we were
// trying to load the master OR while we were disposing of the tech
if (!currentPlaylist) {
this.error = error;
if (this.mediaSource.readyState !== 'open') {
this.trigger('error');
} else {
this.sourceUpdater_.endOfStream('network');
}
return;
}
currentPlaylist.playlistErrors_++;
const playlists = this.masterPlaylistLoader_.master.playlists;
const enabledPlaylists = playlists.filter(isEnabled);
const isFinalRendition = enabledPlaylists.length === 1 && enabledPlaylists[0] === currentPlaylist;
// Don't blacklist the only playlist unless it was blacklisted
// forever
if (playlists.length === 1 && blacklistDuration !== Infinity) {
videojs.log.warn(`Problem encountered with playlist ${currentPlaylist.id}. ` +
'Trying again since it is the only playlist.');
this.tech_.trigger('retryplaylist');
// if this is a final rendition, we should delay
return this.masterPlaylistLoader_.load(isFinalRendition);
}
if (isFinalRendition) {
// Since we're on the final non-blacklisted playlist, and we're about to blacklist
// it, instead of erring the player or retrying this playlist, clear out the current
// blacklist. This allows other playlists to be attempted in case any have been
// fixed.
let reincluded = false;
playlists.forEach((playlist) => {
// skip current playlist which is about to be blacklisted
if (playlist === currentPlaylist) {
return;
}
const excludeUntil = playlist.excludeUntil;
// a playlist cannot be reincluded if it wasn't excluded to begin with.
if (typeof excludeUntil !== 'undefined' && excludeUntil !== Infinity) {
reincluded = true;
delete playlist.excludeUntil;
}
});
if (reincluded) {
videojs.log.warn('Removing other playlists from the exclusion list because the last ' +
'rendition is about to be excluded.');
// Technically we are retrying a playlist, in that we are simply retrying a previous
// playlist. This is needed for users relying on the retryplaylist event to catch a
// case where the player might be stuck and looping through "dead" playlists.
this.tech_.trigger('retryplaylist');
}
}
// Blacklist this playlist
let excludeUntil;
if (currentPlaylist.playlistErrors_ > this.maxPlaylistRetries) {
excludeUntil = Infinity;
} else {
excludeUntil = Date.now() + (blacklistDuration * 1000);
}
currentPlaylist.excludeUntil = excludeUntil;
if (error.reason) {
currentPlaylist.lastExcludeReason_ = error.reason;
}
this.tech_.trigger('blacklistplaylist');
this.tech_.trigger({type: 'usage', name: 'vhs-rendition-blacklisted'});
this.tech_.trigger({type: 'usage', name: 'hls-rendition-blacklisted'});
// TODO: should we select a new playlist if this blacklist wasn't for the currentPlaylist?
// Would be something like media().id !=== currentPlaylist.id and we would need something
// like `pendingMedia` in playlist loaders to check against that too. This will prevent us
// from loading a new playlist on any blacklist.
// Select a new playlist
const nextPlaylist = this.selectPlaylist();
if (!nextPlaylist) {
this.error = 'Playback cannot continue. No available working or supported playlists.';
this.trigger('error');
return;
}
const logFn = error.internal ? this.logger_ : videojs.log.warn;
const errorMessage = error.message ? (' ' + error.message) : '';
logFn(`${(error.internal ? 'Internal problem' : 'Problem')} encountered with playlist ${currentPlaylist.id}.` +
`${errorMessage} Switching to playlist ${nextPlaylist.id}.`);
// if audio group changed reset audio loaders
if (nextPlaylist.attributes.AUDIO !== currentPlaylist.attributes.AUDIO) {
this.delegateLoaders_('audio', ['abort', 'pause']);
}
// if subtitle group changed reset subtitle loaders
if (nextPlaylist.attributes.SUBTITLES !== currentPlaylist.attributes.SUBTITLES) {
this.delegateLoaders_('subtitle', ['abort', 'pause']);
}
this.delegateLoaders_('main', ['abort', 'pause']);
const delayDuration = (nextPlaylist.targetDuration / 2) * 1000 || 5 * 1000;
const shouldDelay = typeof nextPlaylist.lastRequest === 'number' &&
(Date.now() - nextPlaylist.lastRequest) <= delayDuration;
// delay if it's a final rendition or if the last refresh is sooner than half targetDuration
return this.switchMedia_(nextPlaylist, 'exclude', isFinalRendition || shouldDelay);
}
/**
* Pause all segment/playlist loaders
*/
pauseLoading() {
this.delegateLoaders_('all', ['abort', 'pause']);
this.stopABRTimer_();
}
/**
* Call a set of functions in order on playlist loaders, segment loaders,
* or both types of loaders.
*
* @param {string} filter
* Filter loaders that should call fnNames using a string. Can be:
* * all - run on all loaders
* * audio - run on all audio loaders
* * subtitle - run on all subtitle loaders
* * main - run on the main/master loaders
*
* @param {Array|string} fnNames
* A string or array of function names to call.
*/
delegateLoaders_(filter, fnNames) {
const loaders = [];
const dontFilterPlaylist = filter === 'all';
if (dontFilterPlaylist || filter === 'main') {
loaders.push(this.masterPlaylistLoader_);
}
const mediaTypes = [];
if (dontFilterPlaylist || filter === 'audio') {
mediaTypes.push('AUDIO');
}
if (dontFilterPlaylist || filter === 'subtitle') {
mediaTypes.push('CLOSED-CAPTIONS');
mediaTypes.push('SUBTITLES');
}
mediaTypes.forEach((mediaType) => {
const loader = this.mediaTypes_[mediaType] &&
this.mediaTypes_[mediaType].activePlaylistLoader;
if (loader) {
loaders.push(loader);
}
});
['main', 'audio', 'subtitle'].forEach((name) => {
const loader = this[`${name}SegmentLoader_`];
if (loader && (filter === name || filter === 'all')) {
loaders.push(loader);
}
});
loaders.forEach((loader) => fnNames.forEach((fnName) => {
if (typeof loader[fnName] === 'function') {
loader[fnName]();
}
}));
}
/**
* set the current time on all segment loaders
*
* @param {TimeRange} currentTime the current time to set
* @return {TimeRange} the current time
*/
setCurrentTime(currentTime) {
const buffered = Ranges.findRange(this.tech_.buffered(), currentTime);
if (!(this.masterPlaylistLoader_ && this.masterPlaylistLoader_.media())) {
// return immediately if the metadata is not ready yet
return 0;
}
// it's clearly an edge-case but don't thrown an error if asked to
// seek within an empty playlist
if (!this.masterPlaylistLoader_.media().segments) {
return 0;
}
// if the seek location is already buffered, continue buffering as usual
if (buffered && buffered.length) {
return currentTime;
}
// cancel outstanding requests so we begin buffering at the new
// location
this.mainSegmentLoader_.resetEverything();
this.mainSegmentLoader_.abort();
if (this.mediaTypes_.AUDIO.activePlaylistLoader) {
this.audioSegmentLoader_.resetEverything();
this.audioSegmentLoader_.abort();
}
if (this.mediaTypes_.SUBTITLES.activePlaylistLoader) {
this.subtitleSegmentLoader_.resetEverything();
this.subtitleSegmentLoader_.abort();
}
// start segment loader loading in case they are paused
this.load();
}
/**
* get the current duration
*
* @return {TimeRange} the duration
*/
duration() {
if (!this.masterPlaylistLoader_) {
return 0;
}
const media = this.masterPlaylistLoader_.media();
if (!media) {
// no playlists loaded yet, so can't determine a duration
return 0;
}
// Don't rely on the media source for duration in the case of a live playlist since
// setting the native MediaSource's duration to infinity ends up with consequences to
// seekable behavior. See https://github.com/w3c/media-source/issues/5 for details.
//
// This is resolved in the spec by https://github.com/w3c/media-source/pull/92,
// however, few browsers have support for setLiveSeekableRange()
// https://developer.mozilla.org/en-US/docs/Web/API/MediaSource/setLiveSeekableRange
//
// Until a time when the duration of the media source can be set to infinity, and a
// seekable range specified across browsers, just return Infinity.
if (!media.endList) {
return Infinity;
}
// Since this is a VOD video, it is safe to rely on the media source's duration (if
// available). If it's not available, fall back to a playlist-calculated estimate.
if (this.mediaSource) {
return this.mediaSource.duration;
}
return Vhs.Playlist.duration(media);
}
/**
* check the seekable range
*
* @return {TimeRange} the seekable range
*/
seekable() {
return this.seekable_;
}
onSyncInfoUpdate_() {
let audioSeekable;
if (!this.masterPlaylistLoader_) {
return;
}
let media = this.masterPlaylistLoader_.media();
if (!media) {
return;
}
let expired = this.syncController_.getExpiredTime(media, this.duration());
if (expired === null) {
// not enough information to update seekable
return;
}
const master = this.masterPlaylistLoader_.master;
const mainSeekable = Vhs.Playlist.seekable(
media,
expired,
Vhs.Playlist.liveEdgeDelay(master, media)
);
if (mainSeekable.length === 0) {
return;
}
if (this.mediaTypes_.AUDIO.activePlaylistLoader) {
media = this.mediaTypes_.AUDIO.activePlaylistLoader.media();
expired = this.syncController_.getExpiredTime(media, this.duration());
if (expired === null) {
return;
}
audioSeekable = Vhs.Playlist.seekable(
media,
expired,
Vhs.Playlist.liveEdgeDelay(master, media)
);
if (audioSeekable.length === 0) {
return;
}
}
let oldEnd;
let oldStart;
if (this.seekable_ && this.seekable_.length) {
oldEnd = this.seekable_.end(0);
oldStart = this.seekable_.start(0);
}
if (!audioSeekable) {
// seekable has been calculated based on buffering video data so it
// can be returned directly
this.seekable_ = mainSeekable;
} else if (audioSeekable.start(0) > mainSeekable.end(0) ||
mainSeekable.start(0) > audioSeekable.end(0)) {
// seekables are pretty far off, rely on main
this.seekable_ = mainSeekable;
} else {
this.seekable_ = videojs.createTimeRanges([[
(audioSeekable.start(0) > mainSeekable.start(0)) ? audioSeekable.start(0) :
mainSeekable.start(0),
(audioSeekable.end(0) < mainSeekable.end(0)) ? audioSeekable.end(0) :
mainSeekable.end(0)
]]);
}
// seekable is the same as last time
if (this.seekable_ && this.seekable_.length) {
if (this.seekable_.end(0) === oldEnd && this.seekable_.start(0) === oldStart) {
return;
}
}
this.logger_(`seekable updated [${Ranges.printableRange(this.seekable_)}]`);
this.tech_.trigger('seekablechanged');
}
/**
* Update the player duration
*/
updateDuration(isLive) {
if (this.updateDuration_) {
this.mediaSource.removeEventListener('sourceopen', this.updateDuration_);
this.updateDuration_ = null;
}
if (this.mediaSource.readyState !== 'open') {
this.updateDuration_ = this.updateDuration.bind(this, isLive);
this.mediaSource.addEventListener('sourceopen', this.updateDuration_);
return;
}
if (isLive) {
const seekable = this.seekable();
if (!seekable.length) {
return;
}
// Even in the case of a live playlist, the native MediaSource's duration should not
// be set to Infinity (even though this would be expected for a live playlist), since
// setting the native MediaSource's duration to infinity ends up with consequences to
// seekable behavior. See https://github.com/w3c/media-source/issues/5 for details.
//
// This is resolved in the spec by https://github.com/w3c/media-source/pull/92,
// however, few browsers have support for setLiveSeekableRange()
// https://developer.mozilla.org/en-US/docs/Web/API/MediaSource/setLiveSeekableRange
//
// Until a time when the duration of the media source can be set to infinity, and a
// seekable range specified across browsers, the duration should be greater than or
// equal to the last possible seekable value.
// MediaSource duration starts as NaN
// It is possible (and probable) that this case will never be reached for many
// sources, since the MediaSource reports duration as the highest value without
// accounting for timestamp offset. For example, if the timestamp offset is -100 and
// we buffered times 0 to 100 with real times of 100 to 200, even though current
// time will be between 0 and 100, the native media source may report the duration
// as 200. However, since we report duration separate from the media source (as
// Infinity), and as long as the native media source duration value is greater than
// our reported seekable range, seeks will work as expected. The large number as
// duration for live is actually a strategy used by some players to work around the
// issue of live seekable ranges cited above.
if (isNaN(this.mediaSource.duration) || this.mediaSource.duration < seekable.end(seekable.length - 1)) {
this.sourceUpdater_.setDuration(seekable.end(seekable.length - 1));
}
return;
}
const buffered = this.tech_.buffered();
let duration = Vhs.Playlist.duration(this.masterPlaylistLoader_.media());
if (buffered.length > 0) {
duration = Math.max(duration, buffered.end(buffered.length - 1));
}
if (this.mediaSource.duration !== duration) {
this.sourceUpdater_.setDuration(duration);
}
}
/**
* dispose of the MasterPlaylistController and everything
* that it controls
*/
dispose() {
this.trigger('dispose');
this.decrypter_.terminate();
this.masterPlaylistLoader_.dispose();
this.mainSegmentLoader_.dispose();
if (this.loadOnPlay_) {
this.tech_.off('play', this.loadOnPlay_);
}
['AUDIO', 'SUBTITLES'].forEach((type) => {
const groups = this.mediaTypes_[type].groups;
for (const id in groups) {
groups[id].forEach((group) => {
if (group.playlistLoader) {
group.playlistLoader.dispose();
}
});
}
});
this.audioSegmentLoader_.dispose();
this.subtitleSegmentLoader_.dispose();
this.sourceUpdater_.dispose();
this.timelineChangeController_.dispose();
this.stopABRTimer_();
if (this.updateDuration_) {
this.mediaSource.removeEventListener('sourceopen', this.updateDuration_);
}
this.mediaSource.removeEventListener('durationchange', this.handleDurationChange_);
// load the media source into the player
this.mediaSource.removeEventListener('sourceopen', this.handleSourceOpen_);
this.mediaSource.removeEventListener('sourceended', this.handleSourceEnded_);
this.off();
}
/**
* return the master playlist object if we have one
*
* @return {Object} the master playlist object that we parsed
*/
master() {
return this.masterPlaylistLoader_.master;
}
/**
* return the currently selected playlist
*
* @return {Object} the currently selected playlist object that we parsed
*/
media() {
// playlist loader will not return media if it has not been fully loaded
return this.masterPlaylistLoader_.media() || this.initialMedia_;
}
areMediaTypesKnown_() {
const usingAudioLoader = !!this.mediaTypes_.AUDIO.activePlaylistLoader;
// one or both loaders has not loaded sufficently to get codecs
if (!this.mainSegmentLoader_.currentMediaInfo_ || (usingAudioLoader && !this.audioSegmentLoader_.currentMediaInfo_)) {
return false;
}
return true;
}
getCodecsOrExclude_() {
const media = {
main: this.mainSegmentLoader_.currentMediaInfo_ || {},
audio: this.audioSegmentLoader_.currentMediaInfo_ || {}
};
// set "main" media equal to video
media.video = media.main;
const playlistCodecs = codecsForPlaylist(this.master(), this.media());
const codecs = {};
const usingAudioLoader = !!this.mediaTypes_.AUDIO.activePlaylistLoader;
if (media.main.hasVideo) {
codecs.video = playlistCodecs.video || media.main.videoCodec || DEFAULT_VIDEO_CODEC;
}
if (media.main.isMuxed) {
codecs.video += `,${playlistCodecs.audio || media.main.audioCodec || DEFAULT_AUDIO_CODEC}`;
}
if ((media.main.hasAudio && !media.main.isMuxed) || media.audio.hasAudio || usingAudioLoader) {
codecs.audio = playlistCodecs.audio || media.main.audioCodec || media.audio.audioCodec || DEFAULT_AUDIO_CODEC;
// set audio isFmp4 so we use the correct "supports" function below
media.audio.isFmp4 = (media.main.hasAudio && !media.main.isMuxed) ? media.main.isFmp4 : media.audio.isFmp4;
}
// no codecs, no playback.
if (!codecs.audio && !codecs.video) {
this.blacklistCurrentPlaylist({
playlist: this.media(),
message: 'Could not determine codecs for playlist.',
blacklistDuration: Infinity
});
return;
}
// fmp4 relies on browser support, while ts relies on muxer support
const supportFunction = (isFmp4, codec) => (isFmp4 ? browserSupportsCodec(codec) : muxerSupportsCodec(codec));
const unsupportedCodecs = {};
let unsupportedAudio;
['video', 'audio'].forEach(function(type) {
if (codecs.hasOwnProperty(type) && !supportFunction(media[type].isFmp4, codecs[type])) {
const supporter = media[type].isFmp4 ? 'browser' : 'muxer';
unsupportedCodecs[supporter] = unsupportedCodecs[supporter] || [];
unsupportedCodecs[supporter].push(codecs[type]);
if (type === 'audio') {
unsupportedAudio = supporter;
}
}
});
if (usingAudioLoader && unsupportedAudio && this.media().attributes.AUDIO) {
const audioGroup = this.media().attributes.AUDIO;
this.master().playlists.forEach(variant => {
const variantAudioGroup = variant.attributes && variant.attributes.AUDIO;
if (variantAudioGroup === audioGroup && variant !== this.media()) {
variant.excludeUntil = Infinity;
}
});
this.logger_(`excluding audio group ${audioGroup} as ${unsupportedAudio} does not support codec(s): "${codecs.audio}"`);
}
// if we have any unsupported codecs blacklist this playlist.
if (Object.keys(unsupportedCodecs).length) {
const message = Object.keys(unsupportedCodecs).reduce((acc, supporter) => {
if (acc) {
acc += ', ';
}
acc += `${supporter} does not support codec(s): "${unsupportedCodecs[supporter].join(',')}"`;
return acc;
}, '') + '.';
this.blacklistCurrentPlaylist({
playlist: this.media(),
internal: true,
message,
blacklistDuration: Infinity
});
return;
}
// check if codec switching is happening
if (
this.sourceUpdater_.hasCreatedSourceBuffers() &&
!this.sourceUpdater_.canChangeType()
) {
const switchMessages = [];
['video', 'audio'].forEach((type) => {
const newCodec = (parseCodecs(this.sourceUpdater_.codecs[type] || '')[0] || {}).type;
const oldCodec = (parseCodecs(codecs[type] || '')[0] || {}).type;
if (newCodec && oldCodec && newCodec.toLowerCase() !== oldCodec.toLowerCase()) {
switchMessages.push(`"${this.sourceUpdater_.codecs[type]}" -> "${codecs[type]}"`);
}
});
if (switchMessages.length) {
this.blacklistCurrentPlaylist({
playlist: this.media(),
message: `Codec switching not supported: ${switchMessages.join(', ')}.`,
blacklistDuration: Infinity,
internal: true
});
return;
}
}
// TODO: when using the muxer shouldn't we just return
// the codecs that the muxer outputs?
return codecs;
}
/**
* Create source buffers and exlude any incompatible renditions.
*
* @private
*/
tryToCreateSourceBuffers_() {
// media source is not ready yet or sourceBuffers are already
// created.
if (
this.mediaSource.readyState !== 'open' ||
this.sourceUpdater_.hasCreatedSourceBuffers()
) {
return;
}
if (!this.areMediaTypesKnown_()) {
return;
}
const codecs = this.getCodecsOrExclude_();
// no codecs means that the playlist was excluded
if (!codecs) {
return;
}
this.sourceUpdater_.createSourceBuffers(codecs);
const codecString = [codecs.video, codecs.audio].filter(Boolean).join(',');
this.excludeIncompatibleVariants_(codecString);
}
/**
* Excludes playlists with codecs that are unsupported by the muxer and browser.
*/
excludeUnsupportedVariants_() {
const playlists = this.master().playlists;
const ids = [];
// TODO: why don't we have a property to loop through all
// playlist? Why did we ever mix indexes and keys?
Object.keys(playlists).forEach(key => {
const variant = playlists[key];
// check if we already processed this playlist.
if (ids.indexOf(variant.id) !== -1) {
return;
}
ids.push(variant.id);
const codecs = codecsForPlaylist(this.master, variant);
const unsupported = [];
if (codecs.audio && !muxerSupportsCodec(codecs.audio) && !browserSupportsCodec(codecs.audio)) {
unsupported.push(`audio codec ${codecs.audio}`);
}
if (codecs.video && !muxerSupportsCodec(codecs.video) && !browserSupportsCodec(codecs.video)) {
unsupported.push(`video codec ${codecs.video}`);
}
if (codecs.text && codecs.text === 'stpp.ttml.im1t') {
unsupported.push(`text codec ${codecs.text}`);
}
if (unsupported.length) {
variant.excludeUntil = Infinity;
this.logger_(`excluding ${variant.id} for unsupported: ${unsupported.join(', ')}`);
}
});
}
/**
* Blacklist playlists that are known to be codec or
* stream-incompatible with the SourceBuffer configuration. For
* instance, Media Source Extensions would cause the video element to
* stall waiting for video data if you switched from a variant with
* video and audio to an audio-only one.
*
* @param {Object} media a media playlist compatible with the current
* set of SourceBuffers. Variants in the current master playlist that
* do not appear to have compatible codec or stream configurations
* will be excluded from the default playlist selection algorithm
* indefinitely.
* @private
*/
excludeIncompatibleVariants_(codecString) {
const ids = [];
const playlists = this.master().playlists;
const codecs = unwrapCodecList(parseCodecs(codecString));
const codecCount_ = codecCount(codecs);
const videoDetails = codecs.video && parseCodecs(codecs.video)[0] || null;
const audioDetails = codecs.audio && parseCodecs(codecs.audio)[0] || null;
Object.keys(playlists).forEach((key) => {
const variant = playlists[key];
// check if we already processed this playlist.
// or it if it is already excluded forever.
if (ids.indexOf(variant.id) !== -1 || variant.excludeUntil === Infinity) {
return;
}
ids.push(variant.id);
const blacklistReasons = [];
// get codecs from the playlist for this variant
const variantCodecs = codecsForPlaylist(this.masterPlaylistLoader_.master, variant);
const variantCodecCount = codecCount(variantCodecs);
// if no codecs are listed, we cannot determine that this
// variant is incompatible. Wait for mux.js to probe
if (!variantCodecs.audio && !variantCodecs.video) {
return;
}
// TODO: we can support this by removing the
// old media source and creating a new one, but it will take some work.
// The number of streams cannot change
if (variantCodecCount !== codecCount_) {
blacklistReasons.push(`codec count "${variantCodecCount}" !== "${codecCount_}"`);
}
// only exclude playlists by codec change, if codecs cannot switch
// during playback.
if (!this.sourceUpdater_.canChangeType()) {
const variantVideoDetails = variantCodecs.video && parseCodecs(variantCodecs.video)[0] || null;
const variantAudioDetails = variantCodecs.audio && parseCodecs(variantCodecs.audio)[0] || null;
// the video codec cannot change
if (variantVideoDetails && videoDetails && variantVideoDetails.type.toLowerCase() !== videoDetails.type.toLowerCase()) {
blacklistReasons.push(`video codec "${variantVideoDetails.type}" !== "${videoDetails.type}"`);
}
// the audio codec cannot change
if (variantAudioDetails && audioDetails && variantAudioDetails.type.toLowerCase() !== audioDetails.type.toLowerCase()) {
blacklistReasons.push(`audio codec "${variantAudioDetails.type}" !== "${audioDetails.type}"`);
}
}
if (blacklistReasons.length) {
variant.excludeUntil = Infinity;
this.logger_(`blacklisting ${variant.id}: ${blacklistReasons.join(' && ')}`);
}
});
}
updateAdCues_(media) {
let offset = 0;
const seekable = this.seekable();
if (seekable.length) {
offset = seekable.start(0);
}
updateAdCues(media, this.cueTagsTrack_, offset);
}
/**
* Calculates the desired forward buffer length based on current time
*
* @return {number} Desired forward buffer length in seconds
*/
goalBufferLength() {
const currentTime = this.tech_.currentTime();
const initial = Config.GOAL_BUFFER_LENGTH;
const rate = Config.GOAL_BUFFER_LENGTH_RATE;
const max = Math.max(initial, Config.MAX_GOAL_BUFFER_LENGTH);
return Math.min(initial + currentTime * rate, max);
}
/**
* Calculates the desired buffer low water line based on current time
*
* @return {number} Desired buffer low water line in seconds
*/
bufferLowWaterLine() {
const currentTime = this.tech_.currentTime();
const initial = Config.BUFFER_LOW_WATER_LINE;
const rate = Config.BUFFER_LOW_WATER_LINE_RATE;
const max = Math.max(initial, Config.MAX_BUFFER_LOW_WATER_LINE);
const newMax = Math.max(initial, Config.EXPERIMENTAL_MAX_BUFFER_LOW_WATER_LINE);
return Math.min(initial + currentTime * rate, this.experimentalBufferBasedABR ? newMax : max);
}
bufferHighWaterLine() {
return Config.BUFFER_HIGH_WATER_LINE;
}
}