Source: lib/media/media_source_engine.js

  1. /*! @license
  2.  * Shaka Player
  3.  * Copyright 2016 Google LLC
  4.  * SPDX-License-Identifier: Apache-2.0
  5.  */
  7. goog.provide('shaka.media.MediaSourceEngine');
  9. goog.require('goog.asserts');
  10. goog.require('shaka.log');
  11. goog.require('shaka.config.CodecSwitchingStrategy');
  12. goog.require('shaka.media.Capabilities');
  13. goog.require('shaka.media.ContentWorkarounds');
  14. goog.require('shaka.media.ClosedCaptionParser');
  15. goog.require('shaka.media.IClosedCaptionParser');
  16. goog.require('shaka.media.ManifestParser');
  17. goog.require('shaka.media.SegmentReference');
  18. goog.require('shaka.media.TimeRangesUtils');
  19. goog.require('shaka.text.TextEngine');
  20. goog.require('shaka.transmuxer.TransmuxerEngine');
  21. goog.require('shaka.util.BufferUtils');
  22. goog.require('shaka.util.Destroyer');
  23. goog.require('shaka.util.Error');
  24. goog.require('shaka.util.EventManager');
  25. goog.require('shaka.util.Functional');
  26. goog.require('shaka.util.IDestroyable');
  27. goog.require('shaka.util.Id3Utils');
  28. goog.require('shaka.util.ManifestParserUtils');
  29. goog.require('shaka.util.MimeUtils');
  30. goog.require('shaka.util.Mp4BoxParsers');
  31. goog.require('shaka.util.Mp4Parser');
  32. goog.require('shaka.util.Platform');
  33. goog.require('shaka.util.PublicPromise');
  34. goog.require('shaka.util.StreamUtils');
  35. goog.require('shaka.util.TsParser');
  36. goog.require('shaka.lcevc.Dec');
  39. /**
  40.  * @summary
  41.  * MediaSourceEngine wraps all operations on MediaSource and SourceBuffers.
  42.  * All asynchronous operations return a Promise, and all operations are
  43.  * internally synchronized and serialized as needed.  Operations that can
  44.  * be done in parallel will be done in parallel.
  45.  *
  46.  * @implements {shaka.util.IDestroyable}
  47.  */
  48. shaka.media.MediaSourceEngine = class {
  49.   /**
  50.    * @param {HTMLMediaElement} video The video element, whose source is tied to
  51.    *   MediaSource during the lifetime of the MediaSourceEngine.
  52.    * @param {!shaka.extern.TextDisplayer} textDisplayer
  53.    *    The text displayer that will be used with the text engine.
  54.    *    MediaSourceEngine takes ownership of the displayer. When
  55.    *    MediaSourceEngine is destroyed, it will destroy the displayer.
  56.    * @param {!shaka.media.MediaSourceEngine.PlayerInterface} playerInterface
  57.    *   Interface for common player methods.
  58.    * @param {?shaka.lcevc.Dec} [lcevcDec] Optional -  LCEVC Decoder Object
  59.    */
  60.   constructor(video, textDisplayer, playerInterface, lcevcDec) {
  61.     /** @private {HTMLMediaElement} */
  62.     this.video_ = video;
  64.     /** @private {?shaka.media.MediaSourceEngine.PlayerInterface} */
  65.     this.playerInterface_ = playerInterface;
  67.     /** @private {?shaka.extern.MediaSourceConfiguration} */
  68.     this.config_ = null;
  70.     /** @private {shaka.extern.TextDisplayer} */
  71.     this.textDisplayer_ = textDisplayer;
  73.     /** @private {!Object.<shaka.util.ManifestParserUtils.ContentType,
  74.                            SourceBuffer>} */
  75.     this.sourceBuffers_ = {};
  77.     /** @private {!Object.<shaka.util.ManifestParserUtils.ContentType,
  78.                            string>} */
  79.     this.sourceBufferTypes_ = {};
  82.     /** @private {!Object.<shaka.util.ManifestParserUtils.ContentType,
  83.                            boolean>} */
  84.     this.expectedEncryption_ = {};
  86.     /** @private {shaka.text.TextEngine} */
  87.     this.textEngine_ = null;
  89.     /** @private {boolean} */
  90.     this.segmentRelativeVttTiming_ = false;
  92.     /** @private {?shaka.lcevc.Dec} */
  93.     this.lcevcDec_ = lcevcDec || null;
  95.     /**
  96.      * @private {!Object.<string,
  97.      *                    !Array.<shaka.media.MediaSourceEngine.Operation>>}
  98.      */
  99.     this.queues_ = {};
  101.     /** @private {shaka.util.EventManager} */
  102.     this.eventManager_ = new shaka.util.EventManager();
  104.     /** @private {!Object.<string, !shaka.extern.Transmuxer>} */
  105.     this.transmuxers_ = {};
  107.     /** @private {?shaka.media.IClosedCaptionParser} */
  108.     this.captionParser_ = null;
  110.     /** @private {!shaka.util.PublicPromise} */
  111.     this.mediaSourceOpen_ = new shaka.util.PublicPromise();
  113.     /** @private {string} */
  114.     this.url_ = '';
  116.     /** @private {boolean} */
  117.     this.playbackHasBegun_ = false;
  119.     /** @private {MediaSource} */
  120.     this.mediaSource_ = this.createMediaSource(this.mediaSourceOpen_);
  122.     /** @private {boolean} */
  123.     this.reloadingMediaSource_ = false;
  125.     /** @type {!shaka.util.Destroyer} */
  126.     this.destroyer_ = new shaka.util.Destroyer(() => this.doDestroy_());
  128.     /** @private {boolean} */
  129.     this.sequenceMode_ = false;
  131.     /** @private {string} */
  132.     this.manifestType_ = shaka.media.ManifestParser.UNKNOWN;
  134.     /** @private {boolean} */
  135.     this.ignoreManifestTimestampsInSegmentsMode_ = false;
  137.     /** @private {boolean} */
  138.     this.attemptTimestampOffsetCalculation_ = false;
  140.     /** @private {!shaka.util.PublicPromise.<number>} */
  141.     this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
  143.     /** @private {boolean} */
  144.     this.needSplitMuxedContent_ = false;
  146.     /** @private {boolean} */
  147.     this.streamingAllowed_ = true;
  149.     /** @private {?number} */
  150.     this.lastDuration_ = null;
  152.     /** @private {?shaka.util.TsParser} */
  153.     this.tsParser_ = null;
  155.     /** @private {?number} */
  156.     this.firstVideoTimestamp_ = null;
  158.     /** @private {?number} */
  159.     this.firstVideoReferenceStartTime_ = null;
  161.     /** @private {?number} */
  162.     this.firstAudioTimestamp_ = null;
  164.     /** @private {?number} */
  165.     this.firstAudioReferenceStartTime_ = null;
  167.     /** @private {!shaka.util.PublicPromise.<number>} */
  168.     this.audioCompensation_ = new shaka.util.PublicPromise();
  169.   }
  171.   /**
  172.    * Create a MediaSource object, attach it to the video element, and return it.
  173.    * Resolves the given promise when the MediaSource is ready.
  174.    *
  175.    * Replaced by unit tests.
  176.    *
  177.    * @param {!shaka.util.PublicPromise} p
  178.    * @return {!MediaSource}
  179.    */
  180.   createMediaSource(p) {
  181.     this.streamingAllowed_ = true;
  183.     /** @type {!MediaSource} */
  184.     let mediaSource;
  186.     if (window.ManagedMediaSource) {
  187.       this.video_.disableRemotePlayback = true;
  189.       mediaSource = new ManagedMediaSource();
  191.       this.eventManager_.listen(
  192.           mediaSource, 'startstreaming', () => {
  193.             shaka.log.info('MMS startstreaming');
  194.             this.streamingAllowed_ = true;
  195.           });
  197.       this.eventManager_.listen(
  198.           mediaSource, 'endstreaming', () => {
  199.             shaka.log.info('MMS endstreaming');
  200.             this.streamingAllowed_ = false;
  201.           });
  202.     } else {
  203.       mediaSource = new MediaSource();
  204.     }
  206.     // Set up MediaSource on the video element.
  207.     this.eventManager_.listenOnce(
  208.         mediaSource, 'sourceopen', () => this.onSourceOpen_(p));
  210.     // Correctly set when playback has begun.
  211.     this.eventManager_.listenOnce(this.video_, 'playing', () => {
  212.       this.playbackHasBegun_ = true;
  213.     });
  215.     // Store the object URL for releasing it later.
  216.     this.url_ = shaka.media.MediaSourceEngine.createObjectURL(mediaSource);
  218.     this.video_.src = this.url_;
  220.     return mediaSource;
  221.   }
  223.   /**
  224.    * @param {shaka.util.PublicPromise} p
  225.    * @private
  226.    */
  227.   onSourceOpen_(p) {
  228.     goog.asserts.assert(this.url_, 'Must have object URL');
  230.     // Release the object URL that was previously created, to prevent memory
  231.     // leak.
  232.     // createObjectURL creates a strong reference to the MediaSource object
  233.     // inside the browser.  Setting the src of the video then creates another
  234.     // reference within the video element.  revokeObjectURL will remove the
  235.     // strong reference to the MediaSource object, and allow it to be
  236.     // garbage-collected later.
  237.     URL.revokeObjectURL(this.url_);
  238.     p.resolve();
  239.   }
  241.   /**
  242.    * Checks if a certain type is supported.
  243.    *
  244.    * @param {shaka.extern.Stream} stream
  245.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  246.    * @return {!Promise.<boolean>}
  247.    */
  248.   static async isStreamSupported(stream, contentType) {
  249.     if (stream.createSegmentIndex) {
  250.       await stream.createSegmentIndex();
  251.     }
  252.     if (!stream.segmentIndex) {
  253.       return false;
  254.     }
  255.     if (stream.segmentIndex.isEmpty()) {
  256.       return true;
  257.     }
  258.     const MimeUtils = shaka.util.MimeUtils;
  259.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  260.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  261.     const StreamUtils = shaka.util.StreamUtils;
  262.     const seenCombos = new Set();
  263.     // Check each combination of mimeType and codecs within the segment index.
  264.     // Unfortunately we cannot use fullMimeTypes, as we ALSO need to check the
  265.     // getFullTypeWithAllCodecs (for the sake of the transmuxer) and we have no
  266.     // way of going from a full mimeType to a full mimeType with all codecs.
  267.     // As this function is only called in debug mode, a little inefficiency is
  268.     // acceptable.
  269.     for (const ref of stream.segmentIndex) {
  270.       const mimeType = ref.mimeType || stream.mimeType || '';
  271.       let codecs = ref.codecs || stream.codecs || '';
  272.       // Don't check the same combination of mimetype + codecs twice.
  273.       const combo = mimeType + ':' + codecs;
  274.       if (seenCombos.has(combo)) {
  275.         continue;
  276.       }
  277.       seenCombos.add(combo);
  278.       if (contentType == ContentType.TEXT) {
  279.         const fullMimeType = MimeUtils.getFullType(mimeType, codecs);
  280.         if (!shaka.text.TextEngine.isTypeSupported(fullMimeType)) {
  281.           return false;
  282.         }
  283.       } else {
  284.         if (contentType == ContentType.VIDEO) {
  285.           codecs = StreamUtils.getCorrectVideoCodecs(codecs);
  286.         } else if (contentType == ContentType.AUDIO) {
  287.           codecs = StreamUtils.getCorrectAudioCodecs(codecs, mimeType);
  288.         }
  289.         const extendedMimeType = MimeUtils.getExtendedType(
  290.             stream, mimeType, codecs);
  291.         const fullMimeType = MimeUtils.getFullTypeWithAllCodecs(
  292.             mimeType, codecs);
  293.         if (!shaka.media.Capabilities.isTypeSupported(extendedMimeType) &&
  294.             !TransmuxerEngine.isSupported(fullMimeType, stream.type)) {
  295.           return false;
  296.         }
  297.       }
  298.     }
  299.     return true;
  300.   }
  302.   /**
  303.    * Returns a map of MediaSource support for well-known types.
  304.    *
  305.    * @return {!Object.<string, boolean>}
  306.    */
  307.   static probeSupport() {
  308.     const testMimeTypes = [
  309.       // MP4 types
  310.       'video/mp4; codecs="avc1.42E01E"',
  311.       'video/mp4; codecs="avc3.42E01E"',
  312.       'video/mp4; codecs="hev1.1.6.L93.90"',
  313.       'video/mp4; codecs="hvc1.1.6.L93.90"',
  314.       'video/mp4; codecs="hev1.2.4.L153.B0"; eotf="smpte2084"',  // HDR HEVC
  315.       'video/mp4; codecs="hvc1.2.4.L153.B0"; eotf="smpte2084"',  // HDR HEVC
  316.       'video/mp4; codecs="vp9"',
  317.       'video/mp4; codecs="vp09.00.10.08"',
  318.       'video/mp4; codecs="av01.0.01M.08"',
  319.       'video/mp4; codecs="dvh1.20.01"',
  320.       'audio/mp4; codecs="mp4a.40.2"',
  321.       'audio/mp4; codecs="ac-3"',
  322.       'audio/mp4; codecs="ec-3"',
  323.       'audio/mp4; codecs="ac-4.02.01.01"',
  324.       'audio/mp4; codecs="opus"',
  325.       'audio/mp4; codecs="flac"',
  326.       'audio/mp4; codecs="dtsc"', // DTS Digital Surround
  327.       'audio/mp4; codecs="dtse"', // DTS Express
  328.       'audio/mp4; codecs="dtsx"', // DTS:X
  329.       // WebM types
  330.       'video/webm; codecs="vp8"',
  331.       'video/webm; codecs="vp9"',
  332.       'video/webm; codecs="vp09.00.10.08"',
  333.       'audio/webm; codecs="vorbis"',
  334.       'audio/webm; codecs="opus"',
  335.       // MPEG2 TS types (video/ is also used for audio: https://bit.ly/TsMse)
  336.       'video/mp2t; codecs="avc1.42E01E"',
  337.       'video/mp2t; codecs="avc3.42E01E"',
  338.       'video/mp2t; codecs="hvc1.1.6.L93.90"',
  339.       'video/mp2t; codecs="mp4a.40.2"',
  340.       'video/mp2t; codecs="ac-3"',
  341.       'video/mp2t; codecs="ec-3"',
  342.       // WebVTT types
  343.       'text/vtt',
  344.       'application/mp4; codecs="wvtt"',
  345.       // TTML types
  346.       'application/ttml+xml',
  347.       'application/mp4; codecs="stpp"',
  348.       // Containerless types
  349.       ...shaka.util.MimeUtils.RAW_FORMATS,
  350.     ];
  352.     const support = {};
  353.     for (const type of testMimeTypes) {
  354.       if (shaka.text.TextEngine.isTypeSupported(type)) {
  355.         support[type] = true;
  356.       } else if (shaka.util.Platform.supportsMediaSource()) {
  357.         support[type] = shaka.media.Capabilities.isTypeSupported(type) ||
  358.                         shaka.transmuxer.TransmuxerEngine.isSupported(type);
  359.       } else {
  360.         support[type] = shaka.util.Platform.supportsMediaType(type);
  361.       }
  363.       const basicType = type.split(';')[0];
  364.       support[basicType] = support[basicType] || support[type];
  365.     }
  367.     return support;
  368.   }
  370.   /** @override */
  371.   destroy() {
  372.     return this.destroyer_.destroy();
  373.   }
  375.   /** @private */
  376.   async doDestroy_() {
  377.     const Functional = shaka.util.Functional;
  379.     const cleanup = [];
  381.     for (const contentType in this.queues_) {
  382.       // Make a local copy of the queue and the first item.
  383.       const q = this.queues_[contentType];
  384.       const inProgress = q[0];
  386.       // Drop everything else out of the original queue.
  387.       this.queues_[contentType] = q.slice(0, 1);
  389.       // We will wait for this item to complete/fail.
  390.       if (inProgress) {
  391.         cleanup.push(inProgress.p.catch(Functional.noop));
  392.       }
  394.       // The rest will be rejected silently if possible.
  395.       for (const item of q.slice(1)) {
  396.         item.p.reject(shaka.util.Destroyer.destroyedError());
  397.       }
  398.     }
  400.     if (this.textEngine_) {
  401.       cleanup.push(this.textEngine_.destroy());
  402.     }
  403.     if (this.textDisplayer_) {
  404.       cleanup.push(this.textDisplayer_.destroy());
  405.     }
  407.     for (const contentType in this.transmuxers_) {
  408.       cleanup.push(this.transmuxers_[contentType].destroy());
  409.     }
  412.     await Promise.all(cleanup);
  413.     if (this.eventManager_) {
  414.       this.eventManager_.release();
  415.       this.eventManager_ = null;
  416.     }
  418.     if (this.video_) {
  419.       // "unload" the video element.
  420.       this.video_.removeAttribute('src');
  421.       this.video_.load();
  422.       this.video_ = null;
  423.     }
  425.     this.config_ = null;
  426.     this.mediaSource_ = null;
  427.     this.textEngine_ = null;
  428.     this.textDisplayer_ = null;
  429.     this.sourceBuffers_ = {};
  430.     this.transmuxers_ = {};
  431.     this.captionParser_ = null;
  432.     if (goog.DEBUG) {
  433.       for (const contentType in this.queues_) {
  434.         goog.asserts.assert(
  435.             this.queues_[contentType].length == 0,
  436.             contentType + ' queue should be empty after destroy!');
  437.       }
  438.     }
  439.     this.queues_ = {};
  441.     // This object is owned by Player
  442.     this.lcevcDec_ = null;
  444.     this.tsParser_ = null;
  445.     this.playerInterface_ = null;
  446.   }
  448.   /**
  449.    * @return {!Promise} Resolved when MediaSource is open and attached to the
  450.    *   media element.  This process is actually initiated by the constructor.
  451.    */
  452.   open() {
  453.     return this.mediaSourceOpen_;
  454.   }
  456.   /**
  457.    * Initialize MediaSourceEngine.
  458.    *
  459.    * Note that it is not valid to call this multiple times, except to add or
  460.    * reinitialize text streams.
  461.    *
  462.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  463.    *               shaka.extern.Stream>} streamsByType
  464.    *   A map of content types to streams.  All streams must be supported
  465.    *   according to MediaSourceEngine.isStreamSupported.
  466.    * @param {boolean=} sequenceMode
  467.    *   If true, the media segments are appended to the SourceBuffer in strict
  468.    *   sequence.
  469.    * @param {string=} manifestType
  470.    *   Indicates the type of the manifest.
  471.    * @param {boolean=} ignoreManifestTimestampsInSegmentsMode
  472.    *   If true, don't adjust the timestamp offset to account for manifest
  473.    *   segment durations being out of sync with segment durations. In other
  474.    *   words, assume that there are no gaps in the segments when appending
  475.    *   to the SourceBuffer, even if the manifest and segment times disagree.
  476.    *   Indicates if the manifest has text streams.
  477.    *
  478.    * @return {!Promise}
  479.    */
  480.   async init(streamsByType, sequenceMode=false,
  481.       manifestType=shaka.media.ManifestParser.UNKNOWN,
  482.       ignoreManifestTimestampsInSegmentsMode=false) {
  483.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  485.     await this.mediaSourceOpen_;
  487.     this.sequenceMode_ = sequenceMode;
  488.     this.manifestType_ = manifestType;
  489.     this.ignoreManifestTimestampsInSegmentsMode_ =
  490.       ignoreManifestTimestampsInSegmentsMode;
  492.     this.attemptTimestampOffsetCalculation_ = !this.sequenceMode_ &&
  493.         this.manifestType_ == shaka.media.ManifestParser.HLS &&
  494.         !this.ignoreManifestTimestampsInSegmentsMode_;
  496.     this.tsParser_ = null;
  498.     for (const contentType of streamsByType.keys()) {
  499.       const stream = streamsByType.get(contentType);
  500.       // eslint-disable-next-line no-await-in-loop
  501.       await this.initSourceBuffer_(contentType, stream, stream.codecs);
  502.       if (this.needSplitMuxedContent_) {
  503.         this.queues_[ContentType.AUDIO] = [];
  504.         this.queues_[ContentType.VIDEO] = [];
  505.       } else {
  506.         this.queues_[contentType] = [];
  507.       }
  508.     }
  509.   }
  511.   /**
  512.    * Initialize a specific SourceBuffer.
  513.    *
  514.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  515.    * @param {shaka.extern.Stream} stream
  516.    * @param {string} codecs
  517.    * @return {!Promise}
  518.    * @private
  519.    */
  520.   async initSourceBuffer_(contentType, stream, codecs) {
  521.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  523.     goog.asserts.assert(
  524.         await shaka.media.MediaSourceEngine.isStreamSupported(
  525.             stream, contentType),
  526.         'Type negotiation should happen before MediaSourceEngine.init!');
  528.     let mimeType = shaka.util.MimeUtils.getFullType(
  529.         stream.mimeType, codecs);
  530.     if (contentType == ContentType.TEXT) {
  531.       this.reinitText(mimeType, this.sequenceMode_, stream.external);
  532.     } else {
  533.       let needTransmux = this.config_.forceTransmux;
  534.       if (!shaka.media.Capabilities.isTypeSupported(mimeType) ||
  535.           (!this.sequenceMode_ &&
  536.           shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType))) {
  537.         needTransmux = true;
  538.       }
  539.       const mimeTypeWithAllCodecs =
  540.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  541.               stream.mimeType, codecs);
  542.       if (needTransmux) {
  543.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  544.             ContentType.AUDIO, (codecs || '').split(','));
  545.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  546.             ContentType.VIDEO, (codecs || '').split(','));
  547.         if (audioCodec && videoCodec) {
  548.           this.needSplitMuxedContent_ = true;
  549.           await this.initSourceBuffer_(ContentType.AUDIO, stream, audioCodec);
  550.           await this.initSourceBuffer_(ContentType.VIDEO, stream, videoCodec);
  551.           return;
  552.         }
  553.         const transmuxerPlugin = shaka.transmuxer.TransmuxerEngine
  554.             .findTransmuxer(mimeTypeWithAllCodecs);
  555.         if (transmuxerPlugin) {
  556.           const transmuxer = transmuxerPlugin();
  557.           this.transmuxers_[contentType] = transmuxer;
  558.           mimeType =
  559.               transmuxer.convertCodecs(contentType, mimeTypeWithAllCodecs);
  560.         }
  561.       }
  562.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  564.       this.destroyer_.ensureNotDestroyed();
  566.       let sourceBuffer;
  568.       try {
  569.         sourceBuffer = this.mediaSource_.addSourceBuffer(type);
  570.       } catch (exception) {
  571.         throw new shaka.util.Error(
  572.             shaka.util.Error.Severity.CRITICAL,
  573.             shaka.util.Error.Category.MEDIA,
  574.             shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  575.             exception,
  576.             'The mediaSource_ status was ' + this.mediaSource_.readyState +
  577.             ' expected \'open\'',
  578.             null);
  579.       }
  581.       if (this.sequenceMode_) {
  582.         sourceBuffer.mode =
  583.             shaka.media.MediaSourceEngine.SourceBufferMode_.SEQUENCE;
  584.       }
  586.       this.eventManager_.listen(
  587.           sourceBuffer, 'error',
  588.           () => this.onError_(contentType));
  589.       this.eventManager_.listen(
  590.           sourceBuffer, 'updateend',
  591.           () => this.onUpdateEnd_(contentType));
  592.       this.sourceBuffers_[contentType] = sourceBuffer;
  593.       this.sourceBufferTypes_[contentType] = mimeType;
  594.       this.expectedEncryption_[contentType] = !!stream.drmInfos.length;
  595.     }
  596.   }
  598.   /**
  599.    * Called by the Player to provide an updated configuration any time it
  600.    * changes. Must be called at least once before init().
  601.    *
  602.    * @param {shaka.extern.MediaSourceConfiguration} config
  603.    */
  604.   configure(config) {
  605.     this.config_ = config;
  606.     if (this.textEngine_) {
  607.       this.textEngine_.setModifyCueCallback(config.modifyCueCallback);
  608.     }
  609.   }
  611.   /**
  612.    * Indicate if the streaming is allowed by MediaSourceEngine.
  613.    * If we using MediaSource we allways returns true.
  614.    *
  615.    * @return {boolean}
  616.    */
  617.   isStreamingAllowed() {
  618.     return this.streamingAllowed_;
  619.   }
  621.   /**
  622.    * Reinitialize the TextEngine for a new text type.
  623.    * @param {string} mimeType
  624.    * @param {boolean} sequenceMode
  625.    * @param {boolean} external
  626.    */
  627.   reinitText(mimeType, sequenceMode, external) {
  628.     if (!this.textEngine_) {
  629.       this.textEngine_ = new shaka.text.TextEngine(this.textDisplayer_);
  630.       if (this.textEngine_) {
  631.         this.textEngine_.setModifyCueCallback(this.config_.modifyCueCallback);
  632.       }
  633.     }
  634.     this.textEngine_.initParser(mimeType, sequenceMode,
  635.         external || this.segmentRelativeVttTiming_, this.manifestType_);
  636.   }
  638.   /**
  639.    * @return {boolean} True if the MediaSource is in an "ended" state, or if the
  640.    *   object has been destroyed.
  641.    */
  642.   ended() {
  643.     if (this.reloadingMediaSource_) {
  644.       return false;
  645.     }
  646.     return this.mediaSource_ ? this.mediaSource_.readyState == 'ended' : true;
  647.   }
  649.   /**
  650.    * Gets the first timestamp in buffer for the given content type.
  651.    *
  652.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  653.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  654.    */
  655.   bufferStart(contentType) {
  656.     if (!Object.keys(this.sourceBuffers_).length) {
  657.       return null;
  658.     }
  659.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  660.     if (contentType == ContentType.TEXT) {
  661.       return this.textEngine_.bufferStart();
  662.     }
  663.     return shaka.media.TimeRangesUtils.bufferStart(
  664.         this.getBuffered_(contentType));
  665.   }
  667.   /**
  668.    * Gets the last timestamp in buffer for the given content type.
  669.    *
  670.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  671.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  672.    */
  673.   bufferEnd(contentType) {
  674.     if (!Object.keys(this.sourceBuffers_).length) {
  675.       return null;
  676.     }
  677.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  678.     if (contentType == ContentType.TEXT) {
  679.       return this.textEngine_.bufferEnd();
  680.     }
  681.     return shaka.media.TimeRangesUtils.bufferEnd(
  682.         this.getBuffered_(contentType));
  683.   }
  685.   /**
  686.    * Determines if the given time is inside the buffered range of the given
  687.    * content type.
  688.    *
  689.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  690.    * @param {number} time Playhead time
  691.    * @return {boolean}
  692.    */
  693.   isBuffered(contentType, time) {
  694.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  695.     if (contentType == ContentType.TEXT) {
  696.       return this.textEngine_.isBuffered(time);
  697.     } else {
  698.       const buffered = this.getBuffered_(contentType);
  699.       return shaka.media.TimeRangesUtils.isBuffered(buffered, time);
  700.     }
  701.   }
  703.   /**
  704.    * Computes how far ahead of the given timestamp is buffered for the given
  705.    * content type.
  706.    *
  707.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  708.    * @param {number} time
  709.    * @return {number} The amount of time buffered ahead in seconds.
  710.    */
  711.   bufferedAheadOf(contentType, time) {
  712.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  713.     if (contentType == ContentType.TEXT) {
  714.       return this.textEngine_.bufferedAheadOf(time);
  715.     } else {
  716.       const buffered = this.getBuffered_(contentType);
  717.       return shaka.media.TimeRangesUtils.bufferedAheadOf(buffered, time);
  718.     }
  719.   }
  721.   /**
  722.    * Returns info about what is currently buffered.
  723.    * @return {shaka.extern.BufferedInfo}
  724.    */
  725.   getBufferedInfo() {
  726.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  727.     const TimeRangesUtils = shaka.media.TimeRangesUtils;
  729.     const info = {
  730.       total: this.reloadingMediaSource_ ? [] :
  731.         TimeRangesUtils.getBufferedInfo(this.video_.buffered),
  732.       audio:
  733.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.AUDIO)),
  734.       video:
  735.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.VIDEO)),
  736.       text: [],
  737.     };
  739.     if (this.textEngine_) {
  740.       const start = this.textEngine_.bufferStart();
  741.       const end = this.textEngine_.bufferEnd();
  743.       if (start != null && end != null) {
  744.         info.text.push({start: start, end: end});
  745.       }
  746.     }
  747.     return info;
  748.   }
  750.   /**
  751.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  752.    * @return {TimeRanges} The buffered ranges for the given content type, or
  753.    *   null if the buffered ranges could not be obtained.
  754.    * @private
  755.    */
  756.   getBuffered_(contentType) {
  757.     if (this.reloadingMediaSource_) {
  758.       return null;
  759.     }
  760.     try {
  761.       return this.sourceBuffers_[contentType].buffered;
  762.     } catch (exception) {
  763.       if (contentType in this.sourceBuffers_) {
  764.         // Note: previous MediaSource errors may cause access to |buffered| to
  765.         // throw.
  766.         shaka.log.error('failed to get buffered range for ' + contentType,
  767.             exception);
  768.       }
  769.       return null;
  770.     }
  771.   }
  773.   /**
  774.    * Create a new closed caption parser. This will ONLY be replaced by tests as
  775.    * a way to inject fake closed caption parser instances.
  776.    *
  777.    * @param {string} mimeType
  778.    * @return {!shaka.media.IClosedCaptionParser}
  779.    */
  780.   getCaptionParser(mimeType) {
  781.     return new shaka.media.ClosedCaptionParser(mimeType);
  782.   }
  784.   /**
  785.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  786.    * @param {!BufferSource} data
  787.    * @param {?shaka.media.SegmentReference} reference The segment reference
  788.    *   we are appending, or null for init segments
  789.    * @param {!string} mimeType
  790.    * @return {{timestamp: ?number, metadata: !Array.<shaka.extern.ID3Metadata>}}
  791.    * @private
  792.    */
  793.   getTimestampAndDispatchMetadata_(contentType, data, reference, mimeType) {
  794.     let timestamp = null;
  795.     let metadata = [];
  797.     const uint8ArrayData = shaka.util.BufferUtils.toUint8(data);
  798.     if (shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType)) {
  799.       const frames = shaka.util.Id3Utils.getID3Frames(uint8ArrayData);
  800.       if (frames.length && reference) {
  801.         const metadataTimestamp = frames.find((frame) => {
  802.           return frame.description ===
  803.               'com.apple.streaming.transportStreamTimestamp';
  804.         });
  805.         if (metadataTimestamp && metadataTimestamp.data) {
  806.           timestamp = Math.round(metadataTimestamp.data) / 1000;
  807.         }
  808.         /** @private {shaka.extern.ID3Metadata} */
  809.         const id3Metadata = {
  810.           cueTime: reference.startTime,
  811.           data: uint8ArrayData,
  812.           frames: frames,
  813.           dts: reference.startTime,
  814.           pts: reference.startTime,
  815.         };
  816.         this.playerInterface_.onMetadata(
  817.             [id3Metadata], /* offset= */ 0, reference.endTime);
  818.       }
  819.     } else if (mimeType.includes('/mp4') &&
  820.         reference && reference.timestampOffset == 0 &&
  821.         reference.initSegmentReference &&
  822.         reference.initSegmentReference.timescale) {
  823.       const timescale = reference.initSegmentReference.timescale;
  824.       if (!isNaN(timescale)) {
  825.         const Mp4Parser = shaka.util.Mp4Parser;
  826.         let startTime = 0;
  827.         let parsedMedia = false;
  828.         new Mp4Parser()
  829.             .box('moof', Mp4Parser.children)
  830.             .box('traf', Mp4Parser.children)
  831.             .fullBox('tfdt', (box) => {
  832.               goog.asserts.assert(
  833.                   box.version == 0 || box.version == 1,
  834.                   'TFDT version can only be 0 or 1');
  835.               const parsed = shaka.util.Mp4BoxParsers.parseTFDTInaccurate(
  836.                   box.reader, box.version);
  837.               startTime = parsed.baseMediaDecodeTime / timescale;
  838.               parsedMedia = true;
  839.               box.parser.stop();
  840.             }).parse(data, /* partialOkay= */ true);
  841.         if (parsedMedia) {
  842.           timestamp = startTime;
  843.         }
  844.       }
  845.     } else if (!mimeType.includes('/mp4') && !mimeType.includes('/webm') &&
  846.         shaka.util.TsParser.probe(uint8ArrayData)) {
  847.       if (!this.tsParser_) {
  848.         this.tsParser_ = new shaka.util.TsParser();
  849.       } else {
  850.         this.tsParser_.clearData();
  851.       }
  852.       const tsParser = this.tsParser_.parse(uint8ArrayData);
  853.       const startTime = tsParser.getStartTime(contentType);
  854.       if (startTime != null) {
  855.         timestamp = startTime;
  856.       }
  857.       metadata = tsParser.getMetadata();
  858.     }
  859.     return {timestamp, metadata};
  860.   }
  862.   /**
  863.    * Enqueue an operation to append data to the SourceBuffer.
  864.    * Start and end times are needed for TextEngine, but not for MediaSource.
  865.    * Start and end times may be null for initialization segments; if present
  866.    * they are relative to the presentation timeline.
  867.    *
  868.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  869.    * @param {!BufferSource} data
  870.    * @param {?shaka.media.SegmentReference} reference The segment reference
  871.    *   we are appending, or null for init segments
  872.    * @param {shaka.extern.Stream} stream
  873.    * @param {?boolean} hasClosedCaptions True if the buffer contains CEA closed
  874.    *   captions
  875.    * @param {boolean=} seeked True if we just seeked
  876.    * @param {boolean=} adaptation True if we just automatically switched active
  877.    *   variant(s).
  878.    * @param {boolean=} isChunkedData True if we add to the buffer from the
  879.    *   partial read of the segment.
  880.    * @return {!Promise}
  881.    */
  882.   async appendBuffer(
  883.       contentType, data, reference, stream, hasClosedCaptions, seeked = false,
  884.       adaptation = false, isChunkedData = false, fromSplit = false) {
  885.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  887.     if (contentType == ContentType.TEXT) {
  888.       if (this.sequenceMode_) {
  889.         // This won't be known until the first video segment is appended.
  890.         const offset = await this.textSequenceModeOffset_;
  891.         this.textEngine_.setTimestampOffset(offset);
  892.       }
  893.       await this.textEngine_.appendBuffer(
  894.           data,
  895.           reference ? reference.startTime : null,
  896.           reference ? reference.endTime : null,
  897.           reference ? reference.getUris()[0] : null);
  898.       return;
  899.     }
  901.     if (!fromSplit && this.needSplitMuxedContent_) {
  902.       await this.appendBuffer(ContentType.AUDIO, data, reference, stream,
  903.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  904.           /* fromSplit= */ true);
  905.       await this.appendBuffer(ContentType.VIDEO, data, reference, stream,
  906.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  907.           /* fromSplit= */ true);
  908.       return;
  909.     }
  911.     if (!this.sourceBuffers_[contentType]) {
  912.       shaka.log.warning('Attempted to restore a non-existent source buffer');
  913.       return;
  914.     }
  916.     let timestampOffset = this.sourceBuffers_[contentType].timestampOffset;
  918.     let mimeType = this.sourceBufferTypes_[contentType];
  919.     if (this.transmuxers_[contentType]) {
  920.       mimeType = this.transmuxers_[contentType].getOriginalMimeType();
  921.     }
  922.     if (reference) {
  923.       const {timestamp, metadata} = this.getTimestampAndDispatchMetadata_(
  924.           contentType, data, reference, mimeType);
  925.       if (timestamp != null) {
  926.         if (this.firstVideoTimestamp_ == null &&
  927.             contentType == ContentType.VIDEO) {
  928.           this.firstVideoTimestamp_ = timestamp;
  929.           this.firstVideoReferenceStartTime_ = reference.startTime;
  930.           if (this.firstAudioTimestamp_ != null) {
  931.             let compensation = 0;
  932.             // Only apply compensation if video and audio segment startTime
  933.             // match, to avoid introducing sync issues.
  934.             if (this.firstVideoReferenceStartTime_ ==
  935.                 this.firstAudioReferenceStartTime_) {
  936.               compensation =
  937.                   this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  938.             }
  939.             this.audioCompensation_.resolve(compensation);
  940.           }
  941.         }
  942.         if (this.firstAudioTimestamp_ == null &&
  943.             contentType == ContentType.AUDIO) {
  944.           this.firstAudioTimestamp_ = timestamp;
  945.           this.firstAudioReferenceStartTime_ = reference.startTime;
  946.           if (this.firstVideoTimestamp_ != null) {
  947.             let compensation = 0;
  948.             // Only apply compensation if video and audio segment startTime
  949.             // match, to avoid introducing sync issues.
  950.             if (this.firstVideoReferenceStartTime_ ==
  951.                 this.firstAudioReferenceStartTime_) {
  952.               compensation =
  953.                   this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  954.             }
  955.             this.audioCompensation_.resolve(compensation);
  956.           }
  957.         }
  958.         const calculatedTimestampOffset = reference.startTime - timestamp;
  959.         const timestampOffsetDifference =
  960.             Math.abs(timestampOffset - calculatedTimestampOffset);
  961.         if ((timestampOffsetDifference >= 0.001 || seeked || adaptation) &&
  962.             (!isChunkedData || calculatedTimestampOffset > 0 ||
  963.             !timestampOffset)) {
  964.           timestampOffset = calculatedTimestampOffset;
  965.           if (this.attemptTimestampOffsetCalculation_) {
  966.             this.enqueueOperation_(
  967.                 contentType,
  968.                 () => this.abort_(contentType),
  969.                 null);
  970.             this.enqueueOperation_(
  971.                 contentType,
  972.                 () => this.setTimestampOffset_(contentType, timestampOffset),
  973.                 null);
  974.           }
  975.         }
  976.         // Timestamps can only be reliably extracted from video, not audio.
  977.         // Packed audio formats do not have internal timestamps at all.
  978.         // Prefer video for this when available.
  979.         const isBestSourceBufferForTimestamps =
  980.             contentType == ContentType.VIDEO ||
  981.             !(ContentType.VIDEO in this.sourceBuffers_);
  982.         if (this.sequenceMode_ && isBestSourceBufferForTimestamps) {
  983.           this.textSequenceModeOffset_.resolve(timestampOffset);
  984.         }
  985.       }
  986.       if (metadata.length) {
  987.         this.playerInterface_.onMetadata(metadata, timestampOffset,
  988.             reference ? reference.endTime : null);
  989.       }
  990.     }
  991.     if (hasClosedCaptions && contentType == ContentType.VIDEO) {
  992.       if (!this.textEngine_) {
  993.         this.reinitText(shaka.util.MimeUtils.CEA608_CLOSED_CAPTION_MIMETYPE,
  994.             this.sequenceMode_, /* external= */ false);
  995.       }
  996.       if (!this.captionParser_) {
  997.         const basicType = mimeType.split(';', 1)[0];
  998.         this.captionParser_ = this.getCaptionParser(basicType);
  999.       }
  1000.       // If it is the init segment for closed captions, initialize the closed
  1001.       // caption parser.
  1002.       if (!reference) {
  1003.         this.captionParser_.init(data, adaptation);
  1004.       } else {
  1005.         const closedCaptions = this.captionParser_.parseFrom(data);
  1006.         if (closedCaptions.length) {
  1007.           this.textEngine_.storeAndAppendClosedCaptions(
  1008.               closedCaptions,
  1009.               reference.startTime,
  1010.               reference.endTime,
  1011.               timestampOffset);
  1012.         }
  1013.       }
  1014.     }
  1016.     if (this.transmuxers_[contentType]) {
  1017.       data = await this.transmuxers_[contentType].transmux(
  1018.           data, stream, reference, this.mediaSource_.duration, contentType);
  1019.     }
  1021.     data = this.workAroundBrokenPlatforms_(
  1022.         data, reference ? reference.startTime : null, contentType,
  1023.         reference ? reference.getUris()[0] : null);
  1025.     if (reference && this.sequenceMode_ && contentType != ContentType.TEXT) {
  1026.       // In sequence mode, for non-text streams, if we just cleared the buffer
  1027.       // and are either performing an unbuffered seek or handling an automatic
  1028.       // adaptation, we need to set a new timestampOffset on the sourceBuffer.
  1029.       if (seeked || adaptation) {
  1030.         let timestampOffset = reference.startTime;
  1031.         // Audio and video may not be aligned, so we will compensate for audio
  1032.         // if necessary.
  1033.         if (this.manifestType_ == shaka.media.ManifestParser.HLS &&
  1034.             !this.needSplitMuxedContent_ &&
  1035.             contentType == ContentType.AUDIO &&
  1036.             this.sourceBuffers_[ContentType.VIDEO]) {
  1037.           const compensation = await this.audioCompensation_;
  1038.           // Only apply compensation if the difference is greater than 100ms
  1039.           if (Math.abs(compensation) > 0.1) {
  1040.             timestampOffset -= compensation;
  1041.           }
  1042.         }
  1043.         // The logic to call abort() before setting the timestampOffset is
  1044.         // extended during unbuffered seeks or automatic adaptations; it is
  1045.         // possible for the append state to be PARSING_MEDIA_SEGMENT from the
  1046.         // previous SourceBuffer#appendBuffer() call.
  1047.         this.enqueueOperation_(
  1048.             contentType,
  1049.             () => this.abort_(contentType),
  1050.             null);
  1051.         this.enqueueOperation_(
  1052.             contentType,
  1053.             () => this.setTimestampOffset_(contentType, timestampOffset),
  1054.             null);
  1055.       }
  1056.     }
  1058.     let bufferedBefore = null;
  1060.     await this.enqueueOperation_(contentType, () => {
  1061.       if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1062.         bufferedBefore = this.getBuffered_(contentType);
  1063.       }
  1064.       this.append_(contentType, data, timestampOffset);
  1065.     }, reference ? reference.getUris()[0] : null);
  1067.     if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1068.       const bufferedAfter = this.getBuffered_(contentType);
  1069.       const newBuffered = shaka.media.TimeRangesUtils.computeAddedRange(
  1070.           bufferedBefore, bufferedAfter);
  1071.       if (newBuffered) {
  1072.         const segmentDuration = reference.endTime - reference.startTime;
  1073.         const timeAdded = newBuffered.end - newBuffered.start;
  1074.         // Check end times instead of start times.  We may be overwriting a
  1075.         // buffer and only the end changes, and that would be fine.
  1076.         // Also, exclude tiny segments.  Sometimes alignment segments as small
  1077.         // as 33ms are seen in Google DAI content.  For such tiny segments,
  1078.         // half a segment duration would be no issue.
  1079.         const offset = Math.abs(newBuffered.end - reference.endTime);
  1080.         if (segmentDuration > 0.100 && (offset > segmentDuration / 2 ||
  1081.             Math.abs(segmentDuration - timeAdded) > 0.030)) {
  1082.           shaka.log.error('Possible encoding problem detected!',
  1083.               'Unexpected buffered range for reference', reference,
  1084.               'from URIs', reference.getUris(),
  1085.               'should be', {start: reference.startTime, end: reference.endTime},
  1086.               'but got', newBuffered);
  1087.         }
  1088.       }
  1089.     }
  1090.   }
  1092.   /**
  1093.    * Set the selected closed captions Id and language.
  1094.    *
  1095.    * @param {string} id
  1096.    */
  1097.   setSelectedClosedCaptionId(id) {
  1098.     const VIDEO = shaka.util.ManifestParserUtils.ContentType.VIDEO;
  1099.     const videoBufferEndTime = this.bufferEnd(VIDEO) || 0;
  1100.     this.textEngine_.setSelectedClosedCaptionId(id, videoBufferEndTime);
  1101.   }
  1103.   /** Disable embedded closed captions. */
  1104.   clearSelectedClosedCaptionId() {
  1105.     if (this.textEngine_) {
  1106.       this.textEngine_.setSelectedClosedCaptionId('', 0);
  1107.     }
  1108.   }
  1110.   /**
  1111.    * Enqueue an operation to remove data from the SourceBuffer.
  1112.    *
  1113.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1114.    * @param {number} startTime relative to the start of the presentation
  1115.    * @param {number} endTime relative to the start of the presentation
  1116.    * @return {!Promise}
  1117.    */
  1118.   async remove(contentType, startTime, endTime) {
  1119.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1120.     if (contentType == ContentType.TEXT) {
  1121.       await this.textEngine_.remove(startTime, endTime);
  1122.     } else {
  1123.       await this.enqueueOperation_(
  1124.           contentType,
  1125.           () => this.remove_(contentType, startTime, endTime),
  1126.           null);
  1127.       if (this.needSplitMuxedContent_) {
  1128.         await this.enqueueOperation_(
  1129.             ContentType.AUDIO,
  1130.             () => this.remove_(ContentType.AUDIO, startTime, endTime),
  1131.             null);
  1132.       }
  1133.     }
  1134.   }
  1136.   /**
  1137.    * Enqueue an operation to clear the SourceBuffer.
  1138.    *
  1139.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1140.    * @return {!Promise}
  1141.    */
  1142.   async clear(contentType) {
  1143.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1144.     if (contentType == ContentType.TEXT) {
  1145.       if (!this.textEngine_) {
  1146.         return;
  1147.       }
  1148.       await this.textEngine_.remove(0, Infinity);
  1149.     } else {
  1150.       // Note that not all platforms allow clearing to Infinity.
  1151.       await this.enqueueOperation_(
  1152.           contentType,
  1153.           () => this.remove_(contentType, 0, this.mediaSource_.duration),
  1154.           null);
  1155.       if (this.needSplitMuxedContent_) {
  1156.         await this.enqueueOperation_(
  1157.             ContentType.AUDIO,
  1158.             () => this.remove_(
  1159.                 ContentType.AUDIO, 0, this.mediaSource_.duration),
  1160.             null);
  1161.       }
  1162.     }
  1163.   }
  1165.   /**
  1166.    * Fully reset the state of the caption parser owned by MediaSourceEngine.
  1167.    */
  1168.   resetCaptionParser() {
  1169.     if (this.captionParser_) {
  1170.       this.captionParser_.reset();
  1171.     }
  1172.   }
  1174.   /**
  1175.    * Enqueue an operation to flush the SourceBuffer.
  1176.    * This is a workaround for what we believe is a Chromecast bug.
  1177.    *
  1178.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1179.    * @return {!Promise}
  1180.    */
  1181.   async flush(contentType) {
  1182.     // Flush the pipeline.  Necessary on Chromecast, even though we have removed
  1183.     // everything.
  1184.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1185.     if (contentType == ContentType.TEXT) {
  1186.       // Nothing to flush for text.
  1187.       return;
  1188.     }
  1189.     await this.enqueueOperation_(
  1190.         contentType,
  1191.         () => this.flush_(contentType),
  1192.         null);
  1193.     if (this.needSplitMuxedContent_) {
  1194.       await this.enqueueOperation_(
  1195.           ContentType.AUDIO,
  1196.           () => this.flush_(ContentType.AUDIO),
  1197.           null);
  1198.     }
  1199.   }
  1201.   /**
  1202.    * Sets the timestamp offset and append window end for the given content type.
  1203.    *
  1204.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1205.    * @param {number} timestampOffset The timestamp offset.  Segments which start
  1206.    *   at time t will be inserted at time t + timestampOffset instead.  This
  1207.    *   value does not affect segments which have already been inserted.
  1208.    * @param {number} appendWindowStart The timestamp to set the append window
  1209.    *   start to.  For future appends, frames/samples with timestamps less than
  1210.    *   this value will be dropped.
  1211.    * @param {number} appendWindowEnd The timestamp to set the append window end
  1212.    *   to.  For future appends, frames/samples with timestamps greater than this
  1213.    *   value will be dropped.
  1214.    * @param {boolean} ignoreTimestampOffset  If true, the timestampOffset will
  1215.    *   not be applied in this step.
  1216.    * @param {string} mimeType
  1217.    * @param {string} codecs
  1218.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1219.    *               shaka.extern.Stream>} streamsByType
  1220.    *   A map of content types to streams.  All streams must be supported
  1221.    *   according to MediaSourceEngine.isStreamSupported.
  1222.    *
  1223.    * @return {!Promise}
  1224.    */
  1225.   async setStreamProperties(
  1226.       contentType, timestampOffset, appendWindowStart, appendWindowEnd,
  1227.       ignoreTimestampOffset, mimeType, codecs, streamsByType) {
  1228.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1229.     if (contentType == ContentType.TEXT) {
  1230.       if (!ignoreTimestampOffset) {
  1231.         this.textEngine_.setTimestampOffset(timestampOffset);
  1232.       }
  1233.       this.textEngine_.setAppendWindow(appendWindowStart, appendWindowEnd);
  1234.       return;
  1235.     }
  1236.     const operations = [];
  1238.     const hasChangedCodecs = await this.codecSwitchIfNecessary_(
  1239.         contentType, mimeType, codecs, streamsByType);
  1241.     if (!hasChangedCodecs) {
  1242.       // Queue an abort() to help MSE splice together overlapping segments.
  1243.       // We set appendWindowEnd when we change periods in DASH content, and the
  1244.       // period transition may result in overlap.
  1245.       //
  1246.       // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1247.       // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1248.       // timestamp offset.  By calling abort(), we reset the state so we can
  1249.       // set it.
  1250.       operations.push(this.enqueueOperation_(
  1251.           contentType,
  1252.           () => this.abort_(contentType),
  1253.           null));
  1254.       if (this.needSplitMuxedContent_) {
  1255.         operations.push(this.enqueueOperation_(
  1256.             ContentType.AUDIO,
  1257.             () => this.abort_(ContentType.AUDIO),
  1258.             null));
  1259.       }
  1260.     }
  1261.     if (!ignoreTimestampOffset) {
  1262.       operations.push(this.enqueueOperation_(
  1263.           contentType,
  1264.           () => this.setTimestampOffset_(contentType, timestampOffset),
  1265.           null));
  1266.       if (this.needSplitMuxedContent_) {
  1267.         operations.push(this.enqueueOperation_(
  1268.             ContentType.AUDIO,
  1269.             () => this.setTimestampOffset_(
  1270.                 ContentType.AUDIO, timestampOffset),
  1271.             null));
  1272.       }
  1273.     }
  1274.     operations.push(this.enqueueOperation_(
  1275.         contentType,
  1276.         () => this.setAppendWindow_(
  1277.             contentType, appendWindowStart, appendWindowEnd),
  1278.         null));
  1279.     if (this.needSplitMuxedContent_) {
  1280.       operations.push(this.enqueueOperation_(
  1281.           ContentType.AUDIO,
  1282.           () => this.setAppendWindow_(
  1283.               ContentType.AUDIO, appendWindowStart, appendWindowEnd),
  1284.           null));
  1285.     }
  1287.     await Promise.all(operations);
  1288.   }
  1290.   /**
  1291.    * Adjust timestamp offset to maintain AV sync across discontinuities.
  1292.    *
  1293.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1294.    * @param {number} timestampOffset
  1295.    * @return {!Promise}
  1296.    */
  1297.   async resync(contentType, timestampOffset) {
  1298.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1300.     if (contentType == ContentType.TEXT) {
  1301.       // This operation is for audio and video only.
  1302.       return;
  1303.     }
  1305.     // Reset the promise in case the timestamp offset changed during
  1306.     // a period/discontinuity transition.
  1307.     if (contentType == ContentType.VIDEO) {
  1308.       this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
  1309.     }
  1311.     // Queue an abort() to help MSE splice together overlapping segments.
  1312.     // We set appendWindowEnd when we change periods in DASH content, and the
  1313.     // period transition may result in overlap.
  1314.     //
  1315.     // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1316.     // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1317.     // timestamp offset.  By calling abort(), we reset the state so we can
  1318.     // set it.
  1319.     this.enqueueOperation_(
  1320.         contentType,
  1321.         () => this.abort_(contentType),
  1322.         null);
  1323.     if (this.needSplitMuxedContent_) {
  1324.       this.enqueueOperation_(
  1325.           ContentType.AUDIO,
  1326.           () => this.abort_(ContentType.AUDIO),
  1327.           null);
  1328.     }
  1329.     await this.enqueueOperation_(
  1330.         contentType,
  1331.         () => this.setTimestampOffset_(contentType, timestampOffset),
  1332.         null);
  1333.     if (this.needSplitMuxedContent_) {
  1334.       await this.enqueueOperation_(
  1335.           ContentType.AUDIO,
  1336.           () => this.setTimestampOffset_(ContentType.AUDIO, timestampOffset),
  1337.           null);
  1338.     }
  1339.   }
  1341.   /**
  1342.    * @param {string=} reason Valid reasons are 'network' and 'decode'.
  1343.    * @return {!Promise}
  1344.    * @see http://w3c.github.io/media-source/#idl-def-EndOfStreamError
  1345.    */
  1346.   async endOfStream(reason) {
  1347.     await this.enqueueBlockingOperation_(() => {
  1348.       // If endOfStream() has already been called on the media source,
  1349.       // don't call it again. Also do not call if readyState is
  1350.       // 'closed' (not attached to video element) since it is not a
  1351.       // valid operation.
  1352.       if (this.ended() || this.mediaSource_.readyState === 'closed') {
  1353.         return;
  1354.       }
  1355.       // Tizen won't let us pass undefined, but it will let us omit the
  1356.       // argument.
  1357.       if (reason) {
  1358.         this.mediaSource_.endOfStream(reason);
  1359.       } else {
  1360.         this.mediaSource_.endOfStream();
  1361.       }
  1362.     });
  1363.   }
  1365.   /**
  1366.    * @param {number} duration
  1367.    * @return {!Promise}
  1368.    */
  1369.   async setDuration(duration) {
  1370.     await this.enqueueBlockingOperation_(() => {
  1371.       // Reducing the duration causes the MSE removal algorithm to run, which
  1372.       // triggers an 'updateend' event to fire.  To handle this scenario, we
  1373.       // have to insert a dummy operation into the beginning of each queue,
  1374.       // which the 'updateend' handler will remove.
  1375.       if (duration < this.mediaSource_.duration) {
  1376.         for (const contentType in this.sourceBuffers_) {
  1377.           const dummyOperation = {
  1378.             start: () => {},
  1379.             p: new shaka.util.PublicPromise(),
  1380.             uri: null,
  1381.           };
  1382.           this.queues_[contentType].unshift(dummyOperation);
  1383.         }
  1384.       }
  1386.       this.mediaSource_.duration = duration;
  1387.       this.lastDuration_ = duration;
  1388.     });
  1389.   }
  1391.   /**
  1392.    * Get the current MediaSource duration.
  1393.    *
  1394.    * @return {number}
  1395.    */
  1396.   getDuration() {
  1397.     return this.mediaSource_.duration;
  1398.   }
  1400.   /**
  1401.    * Append data to the SourceBuffer.
  1402.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1403.    * @param {BufferSource} data
  1404.    * @param {number} timestampOffset
  1405.    * @private
  1406.    */
  1407.   append_(contentType, data, timestampOffset) {
  1408.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1410.     // Append only video data to the LCEVC Dec.
  1411.     if (contentType == ContentType.VIDEO && this.lcevcDec_) {
  1412.       // Append video buffers to the LCEVC Dec for parsing and storing
  1413.       // of LCEVC data.
  1414.       this.lcevcDec_.appendBuffer(data, timestampOffset);
  1415.     }
  1417.     // This will trigger an 'updateend' event.
  1418.     this.sourceBuffers_[contentType].appendBuffer(data);
  1419.   }
  1421.   /**
  1422.    * Remove data from the SourceBuffer.
  1423.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1424.    * @param {number} startTime relative to the start of the presentation
  1425.    * @param {number} endTime relative to the start of the presentation
  1426.    * @private
  1427.    */
  1428.   remove_(contentType, startTime, endTime) {
  1429.     if (endTime <= startTime) {
  1430.       // Ignore removal of inverted or empty ranges.
  1431.       // Fake 'updateend' event to resolve the operation.
  1432.       this.onUpdateEnd_(contentType);
  1433.       return;
  1434.     }
  1436.     // This will trigger an 'updateend' event.
  1437.     this.sourceBuffers_[contentType].remove(startTime, endTime);
  1438.   }
  1440.   /**
  1441.    * Call abort() on the SourceBuffer.
  1442.    * This resets MSE's last_decode_timestamp on all track buffers, which should
  1443.    * trigger the splicing logic for overlapping segments.
  1444.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1445.    * @private
  1446.    */
  1447.   abort_(contentType) {
  1448.     // Save the append window, which is reset on abort().
  1449.     const appendWindowStart =
  1450.         this.sourceBuffers_[contentType].appendWindowStart;
  1451.     const appendWindowEnd = this.sourceBuffers_[contentType].appendWindowEnd;
  1453.     // This will not trigger an 'updateend' event, since nothing is happening.
  1454.     // This is only to reset MSE internals, not to abort an actual operation.
  1455.     this.sourceBuffers_[contentType].abort();
  1457.     // Restore the append window.
  1458.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1459.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1461.     // Fake an 'updateend' event to resolve the operation.
  1462.     this.onUpdateEnd_(contentType);
  1463.   }
  1465.   /**
  1466.    * Nudge the playhead to force the media pipeline to be flushed.
  1467.    * This seems to be necessary on Chromecast to get new content to replace old
  1468.    * content.
  1469.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1470.    * @private
  1471.    */
  1472.   flush_(contentType) {
  1473.     // Never use flush_ if there's data.  It causes a hiccup in playback.
  1474.     goog.asserts.assert(
  1475.         this.video_.buffered.length == 0, 'MediaSourceEngine.flush_ should ' +
  1476.         'only be used after clearing all data!');
  1478.     // Seeking forces the pipeline to be flushed.
  1479.     this.video_.currentTime -= 0.001;
  1481.     // Fake an 'updateend' event to resolve the operation.
  1482.     this.onUpdateEnd_(contentType);
  1483.   }
  1485.   /**
  1486.    * Set the SourceBuffer's timestamp offset.
  1487.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1488.    * @param {number} timestampOffset
  1489.    * @private
  1490.    */
  1491.   setTimestampOffset_(contentType, timestampOffset) {
  1492.     // Work around for
  1493.     // https://github.com/shaka-project/shaka-player/issues/1281:
  1494.     // TODO(https://bit.ly/2ttKiBU): follow up when this is fixed in Edge
  1495.     if (timestampOffset < 0) {
  1496.       // Try to prevent rounding errors in Edge from removing the first
  1497.       // keyframe.
  1498.       timestampOffset += 0.001;
  1499.     }
  1501.     this.sourceBuffers_[contentType].timestampOffset = timestampOffset;
  1503.     // Fake an 'updateend' event to resolve the operation.
  1504.     this.onUpdateEnd_(contentType);
  1505.   }
  1507.   /**
  1508.    * Set the SourceBuffer's append window end.
  1509.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1510.    * @param {number} appendWindowStart
  1511.    * @param {number} appendWindowEnd
  1512.    * @private
  1513.    */
  1514.   setAppendWindow_(contentType, appendWindowStart, appendWindowEnd) {
  1515.     // You can't set start > end, so first set start to 0, then set the new
  1516.     // end, then set the new start.  That way, there are no intermediate
  1517.     // states which are invalid.
  1518.     this.sourceBuffers_[contentType].appendWindowStart = 0;
  1519.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1520.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1522.     // Fake an 'updateend' event to resolve the operation.
  1523.     this.onUpdateEnd_(contentType);
  1524.   }
  1526.   /**
  1527.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1528.    * @private
  1529.    */
  1530.   onError_(contentType) {
  1531.     const operation = this.queues_[contentType][0];
  1532.     goog.asserts.assert(operation, 'Spurious error event!');
  1533.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1534.         'SourceBuffer should not be updating on error!');
  1535.     const code = this.video_.error ? this.video_.error.code : 0;
  1536.     operation.p.reject(new shaka.util.Error(
  1537.         shaka.util.Error.Severity.CRITICAL,
  1538.         shaka.util.Error.Category.MEDIA,
  1539.         shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_FAILED,
  1540.         code, operation.uri));
  1541.     // Do not pop from queue.  An 'updateend' event will fire next, and to
  1542.     // avoid synchronizing these two event handlers, we will allow that one to
  1543.     // pop from the queue as normal.  Note that because the operation has
  1544.     // already been rejected, the call to resolve() in the 'updateend' handler
  1545.     // will have no effect.
  1546.   }
  1548.   /**
  1549.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1550.    * @private
  1551.    */
  1552.   onUpdateEnd_(contentType) {
  1553.     if (this.reloadingMediaSource_) {
  1554.       return;
  1555.     }
  1556.     const operation = this.queues_[contentType][0];
  1557.     goog.asserts.assert(operation, 'Spurious updateend event!');
  1558.     if (!operation) {
  1559.       return;
  1560.     }
  1561.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1562.         'SourceBuffer should not be updating on updateend!');
  1563.     operation.p.resolve();
  1564.     this.popFromQueue_(contentType);
  1565.   }
  1567.   /**
  1568.    * Enqueue an operation and start it if appropriate.
  1569.    *
  1570.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1571.    * @param {function()} start
  1572.    * @param {?string} uri
  1573.    * @return {!Promise}
  1574.    * @private
  1575.    */
  1576.   enqueueOperation_(contentType, start, uri) {
  1577.     this.destroyer_.ensureNotDestroyed();
  1578.     const operation = {
  1579.       start: start,
  1580.       p: new shaka.util.PublicPromise(),
  1581.       uri,
  1582.     };
  1583.     this.queues_[contentType].push(operation);
  1585.     if (this.queues_[contentType].length == 1) {
  1586.       this.startOperation_(contentType);
  1587.     }
  1588.     return operation.p;
  1589.   }
  1591.   /**
  1592.    * Enqueue an operation which must block all other operations on all
  1593.    * SourceBuffers.
  1594.    *
  1595.    * @param {function():(Promise|undefined)} run
  1596.    * @return {!Promise}
  1597.    * @private
  1598.    */
  1599.   async enqueueBlockingOperation_(run) {
  1600.     this.destroyer_.ensureNotDestroyed();
  1602.     /** @type {!Array.<!shaka.util.PublicPromise>} */
  1603.     const allWaiters = [];
  1605.     // Enqueue a 'wait' operation onto each queue.
  1606.     // This operation signals its readiness when it starts.
  1607.     // When all wait operations are ready, the real operation takes place.
  1608.     for (const contentType in this.sourceBuffers_) {
  1609.       const ready = new shaka.util.PublicPromise();
  1610.       const operation = {
  1611.         start: () => ready.resolve(),
  1612.         p: ready,
  1613.         uri: null,
  1614.       };
  1616.       this.queues_[contentType].push(operation);
  1617.       allWaiters.push(ready);
  1619.       if (this.queues_[contentType].length == 1) {
  1620.         operation.start();
  1621.       }
  1622.     }
  1624.     // Return a Promise to the real operation, which waits to begin until
  1625.     // there are no other in-progress operations on any SourceBuffers.
  1626.     try {
  1627.       await Promise.all(allWaiters);
  1628.     } catch (error) {
  1629.       // One of the waiters failed, which means we've been destroyed.
  1630.       goog.asserts.assert(
  1631.           this.destroyer_.destroyed(), 'Should be destroyed by now');
  1632.       // We haven't popped from the queue.  Canceled waiters have been removed
  1633.       // by destroy.  What's left now should just be resolved waiters.  In
  1634.       // uncompiled mode, we will maintain good hygiene and make sure the
  1635.       // assert at the end of destroy passes.  In compiled mode, the queues
  1636.       // are wiped in destroy.
  1637.       if (goog.DEBUG) {
  1638.         for (const contentType in this.sourceBuffers_) {
  1639.           if (this.queues_[contentType].length) {
  1640.             goog.asserts.assert(
  1641.                 this.queues_[contentType].length == 1,
  1642.                 'Should be at most one item in queue!');
  1643.             goog.asserts.assert(
  1644.                 allWaiters.includes(this.queues_[contentType][0].p),
  1645.                 'The item in queue should be one of our waiters!');
  1646.             this.queues_[contentType].shift();
  1647.           }
  1648.         }
  1649.       }
  1650.       throw error;
  1651.     }
  1653.     if (goog.DEBUG) {
  1654.       // If we did it correctly, nothing is updating.
  1655.       for (const contentType in this.sourceBuffers_) {
  1656.         goog.asserts.assert(
  1657.             this.sourceBuffers_[contentType].updating == false,
  1658.             'SourceBuffers should not be updating after a blocking op!');
  1659.       }
  1660.     }
  1662.     // Run the real operation, which can be asynchronous.
  1663.     try {
  1664.       await run();
  1665.     } catch (exception) {
  1666.       throw new shaka.util.Error(
  1667.           shaka.util.Error.Severity.CRITICAL,
  1668.           shaka.util.Error.Category.MEDIA,
  1669.           shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1670.           exception,
  1671.           this.video_.error || 'No error in the media element',
  1672.           null);
  1673.     } finally {
  1674.       // Unblock the queues.
  1675.       for (const contentType in this.sourceBuffers_) {
  1676.         this.popFromQueue_(contentType);
  1677.       }
  1678.     }
  1679.   }
  1681.   /**
  1682.    * Pop from the front of the queue and start a new operation.
  1683.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1684.    * @private
  1685.    */
  1686.   popFromQueue_(contentType) {
  1687.     // Remove the in-progress operation, which is now complete.
  1688.     this.queues_[contentType].shift();
  1689.     this.startOperation_(contentType);
  1690.   }
  1692.   /**
  1693.    * Starts the next operation in the queue.
  1694.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1695.    * @private
  1696.    */
  1697.   startOperation_(contentType) {
  1698.     // Retrieve the next operation, if any, from the queue and start it.
  1699.     const next = this.queues_[contentType][0];
  1700.     if (next) {
  1701.       try {
  1702.         next.start();
  1703.       } catch (exception) {
  1704.         if (exception.name == 'QuotaExceededError') {
  1705.           next.p.reject(new shaka.util.Error(
  1706.               shaka.util.Error.Severity.CRITICAL,
  1707.               shaka.util.Error.Category.MEDIA,
  1708.               shaka.util.Error.Code.QUOTA_EXCEEDED_ERROR,
  1709.               contentType));
  1710.         } else {
  1711.           next.p.reject(new shaka.util.Error(
  1712.               shaka.util.Error.Severity.CRITICAL,
  1713.               shaka.util.Error.Category.MEDIA,
  1714.               shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1715.               exception,
  1716.               this.video_.error || 'No error in the media element',
  1717.               next.uri));
  1718.         }
  1719.         this.popFromQueue_(contentType);
  1720.       }
  1721.     }
  1722.   }
  1724.   /**
  1725.    * @return {!shaka.extern.TextDisplayer}
  1726.    */
  1727.   getTextDisplayer() {
  1728.     goog.asserts.assert(
  1729.         this.textDisplayer_,
  1730.         'TextDisplayer should only be null when this is destroyed');
  1732.     return this.textDisplayer_;
  1733.   }
  1735.   /**
  1736.    * @param {!shaka.extern.TextDisplayer} textDisplayer
  1737.    */
  1738.   setTextDisplayer(textDisplayer) {
  1739.     const oldTextDisplayer = this.textDisplayer_;
  1740.     this.textDisplayer_ = textDisplayer;
  1741.     if (oldTextDisplayer) {
  1742.       textDisplayer.setTextVisibility(oldTextDisplayer.isTextVisible());
  1743.       oldTextDisplayer.destroy();
  1744.     }
  1745.     if (this.textEngine_) {
  1746.       this.textEngine_.setDisplayer(textDisplayer);
  1747.     }
  1748.   }
  1750.   /**
  1751.    * @param {boolean} segmentRelativeVttTiming
  1752.    */
  1753.   setSegmentRelativeVttTiming(segmentRelativeVttTiming) {
  1754.     this.segmentRelativeVttTiming_ = segmentRelativeVttTiming;
  1755.   }
  1757.   /**
  1758.    * Apply platform-specific transformations to this segment to work around
  1759.    * issues in the platform.
  1760.    *
  1761.    * @param {!BufferSource} segment
  1762.    * @param {?number} startTime
  1763.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1764.    * @param {?string} uri
  1765.    * @return {!BufferSource}
  1766.    * @private
  1767.    */
  1768.   workAroundBrokenPlatforms_(segment, startTime, contentType, uri) {
  1769.     const Platform = shaka.util.Platform;
  1771.     const isInitSegment = startTime == null;
  1772.     const encryptionExpected = this.expectedEncryption_[contentType];
  1773.     const keySystem = this.playerInterface_.getKeySystem();
  1775.     // If:
  1776.     //   1. the configuration tells to insert fake encryption,
  1777.     //   2. and this is an init segment,
  1778.     //   3. and encryption is expected,
  1779.     //   4. and the platform requires encryption in all init segments,
  1780.     //   5. and the content is MP4 (mimeType == "video/mp4" or "audio/mp4"),
  1781.     // then insert fake encryption metadata for init segments that lack it.
  1782.     // The MP4 requirement is because we can currently only do this
  1783.     // transformation on MP4 containers.
  1784.     // See: https://github.com/shaka-project/shaka-player/issues/2759
  1785.     if (this.config_.insertFakeEncryptionInInit &&
  1786.         isInitSegment &&
  1787.         encryptionExpected &&
  1788.         Platform.requiresEncryptionInfoInAllInitSegments(keySystem) &&
  1789.         shaka.util.MimeUtils.getContainerType(
  1790.             this.sourceBufferTypes_[contentType]) == 'mp4') {
  1791.       shaka.log.debug('Forcing fake encryption information in init segment.');
  1792.       segment = shaka.media.ContentWorkarounds.fakeEncryption(segment, uri);
  1793.     }
  1795.     return segment;
  1796.   }
  1798.   /**
  1799.    * Prepare the SourceBuffer to parse a potentially new type or codec.
  1800.    *
  1801.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1802.    * @param {string} mimeType
  1803.    * @param {?shaka.extern.Transmuxer} transmuxer
  1804.    * @private
  1805.    */
  1806.   change_(contentType, mimeType, transmuxer) {
  1807.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1808.     if (contentType === ContentType.TEXT) {
  1809.       shaka.log.debug(`Change not supported for ${contentType}`);
  1810.       return;
  1811.     }
  1812.     shaka.log.debug(
  1813.         `Change Type: ${this.sourceBufferTypes_[contentType]} -> ${mimeType}`);
  1814.     if (shaka.media.Capabilities.isChangeTypeSupported()) {
  1815.       if (this.transmuxers_[contentType]) {
  1816.         this.transmuxers_[contentType].destroy();
  1817.         delete this.transmuxers_[contentType];
  1818.       }
  1819.       if (transmuxer) {
  1820.         this.transmuxers_[contentType] = transmuxer;
  1821.       }
  1822.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  1823.       this.sourceBuffers_[contentType].changeType(type);
  1824.       this.sourceBufferTypes_[contentType] = mimeType;
  1825.     } else {
  1826.       shaka.log.debug('Change Type not supported');
  1827.     }
  1829.     // Fake an 'updateend' event to resolve the operation.
  1830.     this.onUpdateEnd_(contentType);
  1831.   }
  1833.   /**
  1834.    * Enqueue an operation to prepare the SourceBuffer to parse a potentially new
  1835.    * type or codec.
  1836.    *
  1837.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1838.    * @param {string} mimeType
  1839.    * @param {?shaka.extern.Transmuxer} transmuxer
  1840.    * @return {!Promise}
  1841.    */
  1842.   changeType(contentType, mimeType, transmuxer) {
  1843.     return this.enqueueOperation_(
  1844.         contentType,
  1845.         () => this.change_(contentType, mimeType, transmuxer),
  1846.         null);
  1847.   }
  1849.   /**
  1850.    * Resets the MediaSource and re-adds source buffers due to codec mismatch
  1851.    *
  1852.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1853.    *               shaka.extern.Stream>} streamsByType
  1854.    * @private
  1855.    */
  1856.   async reset_(streamsByType) {
  1857.     const Functional = shaka.util.Functional;
  1858.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1859.     this.reloadingMediaSource_ = true;
  1860.     this.needSplitMuxedContent_ = false;
  1861.     const currentTime = this.video_.currentTime;
  1863.     // When codec switching if the user is currently paused we don't want
  1864.     // to trigger a play when switching codec.
  1865.     // Playing can also end up in a paused state after a codec switch
  1866.     // so we need to remember the current states.
  1867.     const previousAutoPlayState = this.video_.autoplay;
  1868.     const previousPausedState = this.video_.paused;
  1869.     if (this.playbackHasBegun_) {
  1870.       // Only set autoplay to false if the video playback has already begun.
  1871.       // When a codec switch happens before playback has begun this can cause
  1872.       // autoplay not to work as expected.
  1873.       this.video_.autoplay = false;
  1874.     }
  1876.     try {
  1877.       this.eventManager_.removeAll();
  1879.       const cleanup = [];
  1880.       for (const contentType in this.transmuxers_) {
  1881.         cleanup.push(this.transmuxers_[contentType].destroy());
  1882.       }
  1883.       for (const contentType in this.queues_) {
  1884.         // Make a local copy of the queue and the first item.
  1885.         const q = this.queues_[contentType];
  1886.         const inProgress = q[0];
  1888.         // Drop everything else out of the original queue.
  1889.         this.queues_[contentType] = q.slice(0, 1);
  1891.         // We will wait for this item to complete/fail.
  1892.         if (inProgress) {
  1893.           cleanup.push(inProgress.p.catch(Functional.noop));
  1894.         }
  1896.         // The rest will be rejected silently if possible.
  1897.         for (const item of q.slice(1)) {
  1898.           item.p.reject(shaka.util.Destroyer.destroyedError());
  1899.         }
  1900.       }
  1901.       for (const contentType in this.sourceBuffers_) {
  1902.         const sourceBuffer = this.sourceBuffers_[contentType];
  1903.         try {
  1904.           this.mediaSource_.removeSourceBuffer(sourceBuffer);
  1905.         } catch (e) {}
  1906.       }
  1907.       await Promise.all(cleanup);
  1908.       this.transmuxers_ = {};
  1909.       this.sourceBuffers_ = {};
  1911.       const previousDuration = this.mediaSource_.duration;
  1912.       this.mediaSourceOpen_ = new shaka.util.PublicPromise();
  1913.       this.mediaSource_ = this.createMediaSource(this.mediaSourceOpen_);
  1914.       await this.mediaSourceOpen_;
  1915.       if (!isNaN(previousDuration) && previousDuration) {
  1916.         this.mediaSource_.duration = previousDuration;
  1917.       } else if (!isNaN(this.lastDuration_) && this.lastDuration_) {
  1918.         this.mediaSource_.duration = this.lastDuration_;
  1919.       }
  1921.       const sourceBufferAdded = new shaka.util.PublicPromise();
  1922.       const sourceBuffers =
  1923.         /** @type {EventTarget} */(this.mediaSource_.sourceBuffers);
  1925.       const totalOfBuffers = streamsByType.size;
  1926.       let numberOfSourceBufferAdded = 0;
  1927.       const onSourceBufferAdded = () => {
  1928.         numberOfSourceBufferAdded++;
  1929.         if (numberOfSourceBufferAdded === totalOfBuffers) {
  1930.           sourceBufferAdded.resolve();
  1931.           this.eventManager_.unlisten(sourceBuffers, 'addsourcebuffer',
  1932.               onSourceBufferAdded);
  1933.         }
  1934.       };
  1936.       this.eventManager_.listen(sourceBuffers, 'addsourcebuffer',
  1937.           onSourceBufferAdded);
  1939.       for (const contentType of streamsByType.keys()) {
  1940.         const stream = streamsByType.get(contentType);
  1941.         // eslint-disable-next-line no-await-in-loop
  1942.         await this.initSourceBuffer_(contentType, stream, stream.codecs);
  1943.         if (this.needSplitMuxedContent_) {
  1944.           this.queues_[ContentType.AUDIO] = [];
  1945.           this.queues_[ContentType.VIDEO] = [];
  1946.         } else {
  1947.           this.queues_[contentType] = [];
  1948.         }
  1949.       }
  1951.       // Fake a seek to catchup the playhead.
  1952.       this.video_.currentTime = currentTime;
  1954.       await sourceBufferAdded;
  1955.     } finally {
  1956.       this.reloadingMediaSource_ = false;
  1958.       this.destroyer_.ensureNotDestroyed();
  1960.       this.eventManager_.listenOnce(this.video_, 'canplaythrough', () => {
  1961.         // Don't use ensureNotDestroyed() from this event listener, because
  1962.         // that results in an uncaught exception.  Instead, just check the
  1963.         // flag.
  1964.         if (this.destroyer_.destroyed()) {
  1965.           return;
  1966.         }
  1968.         this.video_.autoplay = previousAutoPlayState;
  1969.         if (!previousPausedState) {
  1970.           this.video_.play();
  1971.         }
  1972.       });
  1973.     }
  1974.   }
  1976.   /**
  1977.    * Resets the Media Source
  1978.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1979.    *               shaka.extern.Stream>} streamsByType
  1980.    * @return {!Promise}
  1981.    */
  1982.   reset(streamsByType) {
  1983.     return this.enqueueBlockingOperation_(
  1984.         () => this.reset_(streamsByType));
  1985.   }
  1987.   /**
  1988.    * Codec switch if necessary, this will not resolve until the codec
  1989.    * switch is over.
  1990.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1991.    * @param {string} mimeType
  1992.    * @param {string} codecs
  1993.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1994.    *               shaka.extern.Stream>} streamsByType
  1995.    * @return {!Promise.<boolean>} true if there was a codec switch,
  1996.    *                              false otherwise.
  1997.    * @private
  1998.    */
  1999.   async codecSwitchIfNecessary_(contentType, mimeType, codecs, streamsByType) {
  2000.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2001.     if (contentType == ContentType.TEXT) {
  2002.       return false;
  2003.     }
  2004.     const MimeUtils = shaka.util.MimeUtils;
  2005.     const currentCodec = MimeUtils.getNormalizedCodec(
  2006.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  2007.     const currentBasicType = MimeUtils.getBasicType(
  2008.         this.sourceBufferTypes_[contentType]);
  2010.     /** @type {?shaka.extern.Transmuxer} */
  2011.     let transmuxer;
  2012.     let transmuxerMuxed = false;
  2013.     let newMimeType = shaka.util.MimeUtils.getFullType(mimeType, codecs);
  2014.     let needTransmux = this.config_.forceTransmux;
  2015.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2016.         (!this.sequenceMode_ &&
  2017.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2018.       needTransmux = true;
  2019.     }
  2020.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2021.     if (needTransmux) {
  2022.       const newMimeTypeWithAllCodecs =
  2023.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codecs);
  2024.       const transmuxerPlugin =
  2025.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2026.       if (transmuxerPlugin) {
  2027.         transmuxer = transmuxerPlugin();
  2028.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2029.             ContentType.AUDIO, (codecs || '').split(','));
  2030.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2031.             ContentType.VIDEO, (codecs || '').split(','));
  2032.         if (audioCodec && videoCodec) {
  2033.           transmuxerMuxed = true;
  2034.           let codec = videoCodec;
  2035.           if (contentType == ContentType.AUDIO) {
  2036.             codec = audioCodec;
  2037.           }
  2038.           newMimeType = transmuxer.convertCodecs(contentType,
  2039.               shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codec));
  2040.         } else {
  2041.           newMimeType =
  2042.               transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2043.         }
  2044.       }
  2045.     }
  2047.     const newCodec = MimeUtils.getNormalizedCodec(
  2048.         MimeUtils.getCodecs(newMimeType));
  2049.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2051.     // Current/new codecs base and basic type match then no need to switch
  2052.     if (currentCodec === newCodec && currentBasicType === newBasicType) {
  2053.       if (this.transmuxers_[contentType] && !transmuxer) {
  2054.         this.transmuxers_[contentType].destroy();
  2055.         delete this.transmuxers_[contentType];
  2056.       } else if (!this.transmuxers_[contentType] && transmuxer) {
  2057.         this.transmuxers_[contentType] = transmuxer;
  2058.       } else if (transmuxer) {
  2059.         // Compare if the transmuxer is different
  2060.         if (this.transmuxers_[contentType] &&
  2061.             this.transmuxers_[contentType].transmux != transmuxer.transmux) {
  2062.           this.transmuxers_[contentType].destroy();
  2063.           delete this.transmuxers_[contentType];
  2064.           this.transmuxers_[contentType] = transmuxer;
  2065.         } else {
  2066.           transmuxer.destroy();
  2067.         }
  2068.       }
  2069.       return false;
  2070.     }
  2072.     let allowChangeType = true;
  2073.     if (this.needSplitMuxedContent_ || (transmuxerMuxed &&
  2074.         transmuxer && !this.transmuxers_[contentType])) {
  2075.       allowChangeType = false;
  2076.     }
  2078.     if (allowChangeType && this.config_.codecSwitchingStrategy ===
  2079.         shaka.config.CodecSwitchingStrategy.SMOOTH &&
  2080.           shaka.media.Capabilities.isChangeTypeSupported()) {
  2081.       await this.changeType(contentType, newMimeType, transmuxer);
  2082.     } else {
  2083.       if (transmuxer) {
  2084.         transmuxer.destroy();
  2085.       }
  2086.       await this.reset(streamsByType);
  2087.     }
  2088.     return true;
  2089.   }
  2091.   /**
  2092.    * Returns true if it's necessary codec switch to load the new stream.
  2093.    *
  2094.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2095.    * @param {shaka.extern.Stream} stream
  2096.    * @param {string} refMimeType
  2097.    * @param {string} refCodecs
  2098.    * @return {boolean}
  2099.    * @private
  2100.    */
  2101.   isCodecSwitchNecessary_(contentType, stream, refMimeType, refCodecs) {
  2102.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2103.       return false;
  2104.     }
  2105.     const MimeUtils = shaka.util.MimeUtils;
  2106.     const currentCodec = MimeUtils.getNormalizedCodec(
  2107.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  2108.     const currentBasicType = MimeUtils.getBasicType(
  2109.         this.sourceBufferTypes_[contentType]);
  2111.     let newMimeType = shaka.util.MimeUtils.getFullType(refMimeType, refCodecs);
  2112.     let needTransmux = this.config_.forceTransmux;
  2113.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2114.         (!this.sequenceMode_ &&
  2115.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2116.       needTransmux = true;
  2117.     }
  2118.     const newMimeTypeWithAllCodecs =
  2119.         shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  2120.             refMimeType, refCodecs);
  2121.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2122.     if (needTransmux) {
  2123.       const transmuxerPlugin =
  2124.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2125.       if (transmuxerPlugin) {
  2126.         const transmuxer = transmuxerPlugin();
  2127.         newMimeType =
  2128.             transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2129.         transmuxer.destroy();
  2130.       }
  2131.     }
  2133.     const newCodec = MimeUtils.getNormalizedCodec(
  2134.         MimeUtils.getCodecs(newMimeType));
  2135.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2137.     return currentCodec !== newCodec || currentBasicType !== newBasicType;
  2138.   }
  2140.   /**
  2141.    * Returns true if it's necessary reset the media source to load the
  2142.    * new stream.
  2143.    *
  2144.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2145.    * @param {shaka.extern.Stream} stream
  2146.    * @param {string} mimeType
  2147.    * @param {string} codecs
  2148.    * @return {boolean}
  2149.    */
  2150.   isResetMediaSourceNecessary(contentType, stream, mimeType, codecs) {
  2151.     if (!this.isCodecSwitchNecessary_(contentType, stream, mimeType, codecs)) {
  2152.       return false;
  2153.     }
  2155.     return this.config_.codecSwitchingStrategy !==
  2156.         shaka.config.CodecSwitchingStrategy.SMOOTH ||
  2157.         !shaka.media.Capabilities.isChangeTypeSupported() ||
  2158.         this.needSplitMuxedContent_;
  2159.   }
  2161.   /**
  2162.    * Update LCEVC Decoder object when ready for LCEVC Decode.
  2163.    * @param {?shaka.lcevc.Dec} lcevcDec
  2164.    */
  2165.   updateLcevcDec(lcevcDec) {
  2166.     this.lcevcDec_ = lcevcDec;
  2167.   }
  2169.   /**
  2170.    * @param {string} mimeType
  2171.    * @return {string}
  2172.    * @private
  2173.    */
  2174.   addExtraFeaturesToMimeType_(mimeType) {
  2175.     const extraFeatures = this.config_.addExtraFeaturesToSourceBuffer(mimeType);
  2176.     const extendedType = mimeType + extraFeatures;
  2177.     shaka.log.debug('Using full mime type', extendedType);
  2179.     return extendedType;
  2180.   }
  2181. };
  2184. /**
  2185.  * Internal reference to window.URL.createObjectURL function to avoid
  2186.  * compatibility issues with other libraries and frameworks such as React
  2187.  * Native. For use in unit tests only, not meant for external use.
  2188.  *
  2189.  * @type {function(?):string}
  2190.  */
  2191. shaka.media.MediaSourceEngine.createObjectURL = window.URL.createObjectURL;
  2194. /**
  2195.  * @typedef {{
  2196.  *   start: function(),
  2197.  *   p: !shaka.util.PublicPromise,
  2198.  *   uri: ?string
  2199.  * }}
  2200.  *
  2201.  * @summary An operation in queue.
  2202.  * @property {function()} start
  2203.  *   The function which starts the operation.
  2204.  * @property {!shaka.util.PublicPromise} p
  2205.  *   The PublicPromise which is associated with this operation.
  2206.  * @property {?string} uri
  2207.  *   A segment URI (if any) associated with this operation.
  2208.  */
  2209. shaka.media.MediaSourceEngine.Operation;
  2212. /**
  2213.  * @enum {string}
  2214.  * @private
  2215.  */
  2216. shaka.media.MediaSourceEngine.SourceBufferMode_ = {
  2217.   SEQUENCE: 'sequence',
  2218.   SEGMENTS: 'segments',
  2219. };
  2222. /**
  2223.  * @typedef {{
  2224.  *   getKeySystem: function():?string,
  2225.  *   onMetadata: function(!Array<shaka.extern.ID3Metadata>, number, ?number)
  2226.  * }}
  2227.  *
  2228.  * @summary Player interface
  2229.  * @property {function():?string} getKeySystem
  2230.  *   Gets currently used key system or null if not used.
  2231.  * @property {function(
  2232.  *     !Array<shaka.extern.ID3Metadata>, number, ?number)} onMetadata
  2233.  *   Callback to use when metadata arrives.
  2234.  */
  2235. shaka.media.MediaSourceEngine.PlayerInterface;