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 {!Object.<shaka.util.ManifestParserUtils.ContentType,
  153.                            !shaka.util.TsParser>} */
  154.     this.tsParsers_ = {};
  156.     /** @private {?number} */
  157.     this.firstVideoTimestamp_ = null;
  159.     /** @private {?number} */
  160.     this.firstVideoReferenceStartTime_ = null;
  162.     /** @private {?number} */
  163.     this.firstAudioTimestamp_ = null;
  165.     /** @private {?number} */
  166.     this.firstAudioReferenceStartTime_ = null;
  168.     /** @private {!shaka.util.PublicPromise.<number>} */
  169.     this.audioCompensation_ = new shaka.util.PublicPromise();
  170.   }
  172.   /**
  173.    * Create a MediaSource object, attach it to the video element, and return it.
  174.    * Resolves the given promise when the MediaSource is ready.
  175.    *
  176.    * Replaced by unit tests.
  177.    *
  178.    * @param {!shaka.util.PublicPromise} p
  179.    * @return {!MediaSource}
  180.    */
  181.   createMediaSource(p) {
  182.     this.streamingAllowed_ = true;
  184.     /** @type {!MediaSource} */
  185.     let mediaSource;
  187.     if (window.ManagedMediaSource) {
  188.       this.video_.disableRemotePlayback = true;
  190.       mediaSource = new ManagedMediaSource();
  192.       this.eventManager_.listen(
  193.           mediaSource, 'startstreaming', () => {
  194.             shaka.log.info('MMS startstreaming');
  195.             this.streamingAllowed_ = true;
  196.           });
  198.       this.eventManager_.listen(
  199.           mediaSource, 'endstreaming', () => {
  200.             shaka.log.info('MMS endstreaming');
  201.             this.streamingAllowed_ = false;
  202.           });
  203.     } else {
  204.       mediaSource = new MediaSource();
  205.     }
  207.     // Set up MediaSource on the video element.
  208.     this.eventManager_.listenOnce(
  209.         mediaSource, 'sourceopen', () => this.onSourceOpen_(p));
  211.     // Correctly set when playback has begun.
  212.     this.eventManager_.listenOnce(this.video_, 'playing', () => {
  213.       this.playbackHasBegun_ = true;
  214.     });
  216.     // Store the object URL for releasing it later.
  217.     this.url_ = shaka.media.MediaSourceEngine.createObjectURL(mediaSource);
  219.     this.video_.src = this.url_;
  221.     return mediaSource;
  222.   }
  224.   /**
  225.    * @param {shaka.util.PublicPromise} p
  226.    * @private
  227.    */
  228.   onSourceOpen_(p) {
  229.     goog.asserts.assert(this.url_, 'Must have object URL');
  231.     // Release the object URL that was previously created, to prevent memory
  232.     // leak.
  233.     // createObjectURL creates a strong reference to the MediaSource object
  234.     // inside the browser.  Setting the src of the video then creates another
  235.     // reference within the video element.  revokeObjectURL will remove the
  236.     // strong reference to the MediaSource object, and allow it to be
  237.     // garbage-collected later.
  238.     URL.revokeObjectURL(this.url_);
  239.     p.resolve();
  240.   }
  242.   /**
  243.    * Checks if a certain type is supported.
  244.    *
  245.    * @param {shaka.extern.Stream} stream
  246.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  247.    * @return {!Promise.<boolean>}
  248.    */
  249.   static async isStreamSupported(stream, contentType) {
  250.     if (stream.createSegmentIndex) {
  251.       await stream.createSegmentIndex();
  252.     }
  253.     if (!stream.segmentIndex) {
  254.       return false;
  255.     }
  256.     if (stream.segmentIndex.isEmpty()) {
  257.       return true;
  258.     }
  259.     const MimeUtils = shaka.util.MimeUtils;
  260.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  261.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  262.     const StreamUtils = shaka.util.StreamUtils;
  263.     const seenCombos = new Set();
  264.     // Check each combination of mimeType and codecs within the segment index.
  265.     // Unfortunately we cannot use fullMimeTypes, as we ALSO need to check the
  266.     // getFullTypeWithAllCodecs (for the sake of the transmuxer) and we have no
  267.     // way of going from a full mimeType to a full mimeType with all codecs.
  268.     // As this function is only called in debug mode, a little inefficiency is
  269.     // acceptable.
  270.     for (const ref of stream.segmentIndex) {
  271.       const mimeType = ref.mimeType || stream.mimeType || '';
  272.       let codecs = ref.codecs || stream.codecs || '';
  273.       // Don't check the same combination of mimetype + codecs twice.
  274.       const combo = mimeType + ':' + codecs;
  275.       if (seenCombos.has(combo)) {
  276.         continue;
  277.       }
  278.       seenCombos.add(combo);
  279.       if (contentType == ContentType.TEXT) {
  280.         const fullMimeType = MimeUtils.getFullType(mimeType, codecs);
  281.         if (!shaka.text.TextEngine.isTypeSupported(fullMimeType)) {
  282.           return false;
  283.         }
  284.       } else {
  285.         if (contentType == ContentType.VIDEO) {
  286.           codecs = StreamUtils.getCorrectVideoCodecs(codecs);
  287.         } else if (contentType == ContentType.AUDIO) {
  288.           codecs = StreamUtils.getCorrectAudioCodecs(codecs, mimeType);
  289.         }
  290.         const extendedMimeType = MimeUtils.getExtendedType(
  291.             stream, mimeType, codecs);
  292.         const fullMimeType = MimeUtils.getFullTypeWithAllCodecs(
  293.             mimeType, codecs);
  294.         if (!shaka.media.Capabilities.isTypeSupported(extendedMimeType) &&
  295.             !TransmuxerEngine.isSupported(fullMimeType, stream.type)) {
  296.           return false;
  297.         }
  298.       }
  299.     }
  300.     return true;
  301.   }
  303.   /**
  304.    * Returns a map of MediaSource support for well-known types.
  305.    *
  306.    * @return {!Object.<string, boolean>}
  307.    */
  308.   static probeSupport() {
  309.     const testMimeTypes = [
  310.       // MP4 types
  311.       'video/mp4; codecs="avc1.42E01E"',
  312.       'video/mp4; codecs="avc3.42E01E"',
  313.       'video/mp4; codecs="hev1.1.6.L93.90"',
  314.       'video/mp4; codecs="hvc1.1.6.L93.90"',
  315.       'video/mp4; codecs="hev1.2.4.L153.B0"; eotf="smpte2084"',  // HDR HEVC
  316.       'video/mp4; codecs="hvc1.2.4.L153.B0"; eotf="smpte2084"',  // HDR HEVC
  317.       'video/mp4; codecs="vp9"',
  318.       'video/mp4; codecs="vp09.00.10.08"',
  319.       'video/mp4; codecs="av01.0.01M.08"',
  320.       'video/mp4; codecs="dvh1.20.01"',
  321.       'audio/mp4; codecs="mp4a.40.2"',
  322.       'audio/mp4; codecs="ac-3"',
  323.       'audio/mp4; codecs="ec-3"',
  324.       'audio/mp4; codecs="ac-4.02.01.01"',
  325.       'audio/mp4; codecs="opus"',
  326.       'audio/mp4; codecs="flac"',
  327.       'audio/mp4; codecs="dtsc"', // DTS Digital Surround
  328.       'audio/mp4; codecs="dtse"', // DTS Express
  329.       'audio/mp4; codecs="dtsx"', // DTS:X
  330.       // WebM types
  331.       'video/webm; codecs="vp8"',
  332.       'video/webm; codecs="vp9"',
  333.       'video/webm; codecs="vp09.00.10.08"',
  334.       'audio/webm; codecs="vorbis"',
  335.       'audio/webm; codecs="opus"',
  336.       // MPEG2 TS types (video/ is also used for audio: https://bit.ly/TsMse)
  337.       'video/mp2t; codecs="avc1.42E01E"',
  338.       'video/mp2t; codecs="avc3.42E01E"',
  339.       'video/mp2t; codecs="hvc1.1.6.L93.90"',
  340.       'video/mp2t; codecs="mp4a.40.2"',
  341.       'video/mp2t; codecs="ac-3"',
  342.       'video/mp2t; codecs="ec-3"',
  343.       // WebVTT types
  344.       'text/vtt',
  345.       'application/mp4; codecs="wvtt"',
  346.       // TTML types
  347.       'application/ttml+xml',
  348.       'application/mp4; codecs="stpp"',
  349.       // Containerless types
  350.       ...shaka.util.MimeUtils.RAW_FORMATS,
  351.     ];
  353.     const support = {};
  354.     for (const type of testMimeTypes) {
  355.       if (shaka.text.TextEngine.isTypeSupported(type)) {
  356.         support[type] = true;
  357.       } else if (shaka.util.Platform.supportsMediaSource()) {
  358.         support[type] = shaka.media.Capabilities.isTypeSupported(type) ||
  359.                         shaka.transmuxer.TransmuxerEngine.isSupported(type);
  360.       } else {
  361.         support[type] = shaka.util.Platform.supportsMediaType(type);
  362.       }
  364.       const basicType = type.split(';')[0];
  365.       support[basicType] = support[basicType] || support[type];
  366.     }
  368.     return support;
  369.   }
  371.   /** @override */
  372.   destroy() {
  373.     return this.destroyer_.destroy();
  374.   }
  376.   /** @private */
  377.   async doDestroy_() {
  378.     const Functional = shaka.util.Functional;
  380.     const cleanup = [];
  382.     for (const contentType in this.queues_) {
  383.       // Make a local copy of the queue and the first item.
  384.       const q = this.queues_[contentType];
  385.       const inProgress = q[0];
  387.       // Drop everything else out of the original queue.
  388.       this.queues_[contentType] = q.slice(0, 1);
  390.       // We will wait for this item to complete/fail.
  391.       if (inProgress) {
  392.         cleanup.push(inProgress.p.catch(Functional.noop));
  393.       }
  395.       // The rest will be rejected silently if possible.
  396.       for (const item of q.slice(1)) {
  397.         item.p.reject(shaka.util.Destroyer.destroyedError());
  398.       }
  399.     }
  401.     if (this.textEngine_) {
  402.       cleanup.push(this.textEngine_.destroy());
  403.     }
  405.     for (const contentType in this.transmuxers_) {
  406.       cleanup.push(this.transmuxers_[contentType].destroy());
  407.     }
  410.     await Promise.all(cleanup);
  411.     if (this.eventManager_) {
  412.       this.eventManager_.release();
  413.       this.eventManager_ = null;
  414.     }
  416.     if (this.video_) {
  417.       // "unload" the video element.
  418.       this.video_.removeAttribute('src');
  419.       this.video_.load();
  420.       this.video_ = null;
  421.     }
  423.     this.config_ = null;
  424.     this.mediaSource_ = null;
  425.     this.textEngine_ = null;
  426.     this.textDisplayer_ = null;
  427.     this.sourceBuffers_ = {};
  428.     this.transmuxers_ = {};
  429.     this.captionParser_ = null;
  430.     if (goog.DEBUG) {
  431.       for (const contentType in this.queues_) {
  432.         goog.asserts.assert(
  433.             this.queues_[contentType].length == 0,
  434.             contentType + ' queue should be empty after destroy!');
  435.       }
  436.     }
  437.     this.queues_ = {};
  439.     // This object is owned by Player
  440.     this.lcevcDec_ = null;
  442.     this.tsParsers_ = {};
  443.     this.playerInterface_ = null;
  444.   }
  446.   /**
  447.    * @return {!Promise} Resolved when MediaSource is open and attached to the
  448.    *   media element.  This process is actually initiated by the constructor.
  449.    */
  450.   open() {
  451.     return this.mediaSourceOpen_;
  452.   }
  454.   /**
  455.    * Initialize MediaSourceEngine.
  456.    *
  457.    * Note that it is not valid to call this multiple times, except to add or
  458.    * reinitialize text streams.
  459.    *
  460.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  461.    *               shaka.extern.Stream>} streamsByType
  462.    *   A map of content types to streams.  All streams must be supported
  463.    *   according to MediaSourceEngine.isStreamSupported.
  464.    * @param {boolean=} sequenceMode
  465.    *   If true, the media segments are appended to the SourceBuffer in strict
  466.    *   sequence.
  467.    * @param {string=} manifestType
  468.    *   Indicates the type of the manifest.
  469.    * @param {boolean=} ignoreManifestTimestampsInSegmentsMode
  470.    *   If true, don't adjust the timestamp offset to account for manifest
  471.    *   segment durations being out of sync with segment durations. In other
  472.    *   words, assume that there are no gaps in the segments when appending
  473.    *   to the SourceBuffer, even if the manifest and segment times disagree.
  474.    *   Indicates if the manifest has text streams.
  475.    *
  476.    * @return {!Promise}
  477.    */
  478.   async init(streamsByType, sequenceMode=false,
  479.       manifestType=shaka.media.ManifestParser.UNKNOWN,
  480.       ignoreManifestTimestampsInSegmentsMode=false) {
  481.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  483.     await this.mediaSourceOpen_;
  485.     this.sequenceMode_ = sequenceMode;
  486.     this.manifestType_ = manifestType;
  487.     this.ignoreManifestTimestampsInSegmentsMode_ =
  488.       ignoreManifestTimestampsInSegmentsMode;
  490.     this.attemptTimestampOffsetCalculation_ = !this.sequenceMode_ &&
  491.         this.manifestType_ == shaka.media.ManifestParser.HLS &&
  492.         !this.ignoreManifestTimestampsInSegmentsMode_;
  494.     this.tsParsers_ = {};
  496.     for (const contentType of streamsByType.keys()) {
  497.       const stream = streamsByType.get(contentType);
  498.       // eslint-disable-next-line no-await-in-loop
  499.       await this.initSourceBuffer_(contentType, stream, stream.codecs);
  500.       if (this.needSplitMuxedContent_) {
  501.         this.queues_[ContentType.AUDIO] = [];
  502.         this.queues_[ContentType.VIDEO] = [];
  503.       } else {
  504.         this.queues_[contentType] = [];
  505.       }
  506.     }
  507.   }
  509.   /**
  510.    * Initialize a specific SourceBuffer.
  511.    *
  512.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  513.    * @param {shaka.extern.Stream} stream
  514.    * @param {string} codecs
  515.    * @return {!Promise}
  516.    * @private
  517.    */
  518.   async initSourceBuffer_(contentType, stream, codecs) {
  519.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  521.     goog.asserts.assert(
  522.         await shaka.media.MediaSourceEngine.isStreamSupported(
  523.             stream, contentType),
  524.         'Type negotiation should happen before MediaSourceEngine.init!');
  526.     let mimeType = shaka.util.MimeUtils.getFullType(
  527.         stream.mimeType, codecs);
  528.     if (contentType == ContentType.TEXT) {
  529.       this.reinitText(mimeType, this.sequenceMode_, stream.external);
  530.     } else {
  531.       let needTransmux = this.config_.forceTransmux;
  532.       if (!shaka.media.Capabilities.isTypeSupported(mimeType) ||
  533.           (!this.sequenceMode_ &&
  534.           shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType))) {
  535.         needTransmux = true;
  536.       }
  537.       const mimeTypeWithAllCodecs =
  538.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  539.               stream.mimeType, codecs);
  540.       if (needTransmux) {
  541.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  542.             ContentType.AUDIO, (codecs || '').split(','));
  543.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  544.             ContentType.VIDEO, (codecs || '').split(','));
  545.         if (audioCodec && videoCodec) {
  546.           this.needSplitMuxedContent_ = true;
  547.           await this.initSourceBuffer_(ContentType.AUDIO, stream, audioCodec);
  548.           await this.initSourceBuffer_(ContentType.VIDEO, stream, videoCodec);
  549.           return;
  550.         }
  551.         const transmuxerPlugin = shaka.transmuxer.TransmuxerEngine
  552.             .findTransmuxer(mimeTypeWithAllCodecs);
  553.         if (transmuxerPlugin) {
  554.           const transmuxer = transmuxerPlugin();
  555.           this.transmuxers_[contentType] = transmuxer;
  556.           mimeType =
  557.               transmuxer.convertCodecs(contentType, mimeTypeWithAllCodecs);
  558.         }
  559.       }
  560.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  562.       this.destroyer_.ensureNotDestroyed();
  564.       let sourceBuffer;
  566.       try {
  567.         sourceBuffer = this.mediaSource_.addSourceBuffer(type);
  568.       } catch (exception) {
  569.         throw new shaka.util.Error(
  570.             shaka.util.Error.Severity.CRITICAL,
  571.             shaka.util.Error.Category.MEDIA,
  572.             shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  573.             exception,
  574.             'The mediaSource_ status was ' + this.mediaSource_.readyState +
  575.             ' expected \'open\'',
  576.             null);
  577.       }
  579.       if (this.sequenceMode_) {
  580.         sourceBuffer.mode =
  581.             shaka.media.MediaSourceEngine.SourceBufferMode_.SEQUENCE;
  582.       }
  584.       this.eventManager_.listen(
  585.           sourceBuffer, 'error',
  586.           () => this.onError_(contentType));
  587.       this.eventManager_.listen(
  588.           sourceBuffer, 'updateend',
  589.           () => this.onUpdateEnd_(contentType));
  590.       this.sourceBuffers_[contentType] = sourceBuffer;
  591.       this.sourceBufferTypes_[contentType] = mimeType;
  592.       this.expectedEncryption_[contentType] = !!stream.drmInfos.length;
  593.     }
  594.   }
  596.   /**
  597.    * Called by the Player to provide an updated configuration any time it
  598.    * changes. Must be called at least once before init().
  599.    *
  600.    * @param {shaka.extern.MediaSourceConfiguration} config
  601.    */
  602.   configure(config) {
  603.     this.config_ = config;
  604.     if (this.textEngine_) {
  605.       this.textEngine_.setModifyCueCallback(config.modifyCueCallback);
  606.     }
  607.   }
  609.   /**
  610.    * Indicate if the streaming is allowed by MediaSourceEngine.
  611.    * If we using MediaSource we allways returns true.
  612.    *
  613.    * @return {boolean}
  614.    */
  615.   isStreamingAllowed() {
  616.     return this.streamingAllowed_;
  617.   }
  619.   /**
  620.    * Reinitialize the TextEngine for a new text type.
  621.    * @param {string} mimeType
  622.    * @param {boolean} sequenceMode
  623.    * @param {boolean} external
  624.    */
  625.   reinitText(mimeType, sequenceMode, external) {
  626.     if (!this.textEngine_) {
  627.       this.textEngine_ = new shaka.text.TextEngine(this.textDisplayer_);
  628.       if (this.textEngine_) {
  629.         this.textEngine_.setModifyCueCallback(this.config_.modifyCueCallback);
  630.       }
  631.     }
  632.     this.textEngine_.initParser(mimeType, sequenceMode,
  633.         external || this.segmentRelativeVttTiming_, this.manifestType_);
  634.   }
  636.   /**
  637.    * @return {boolean} True if the MediaSource is in an "ended" state, or if the
  638.    *   object has been destroyed.
  639.    */
  640.   ended() {
  641.     if (this.reloadingMediaSource_) {
  642.       return false;
  643.     }
  644.     return this.mediaSource_ ? this.mediaSource_.readyState == 'ended' : true;
  645.   }
  647.   /**
  648.    * Gets the first timestamp in buffer for the given content type.
  649.    *
  650.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  651.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  652.    */
  653.   bufferStart(contentType) {
  654.     if (!Object.keys(this.sourceBuffers_).length) {
  655.       return null;
  656.     }
  657.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  658.     if (contentType == ContentType.TEXT) {
  659.       return this.textEngine_.bufferStart();
  660.     }
  661.     return shaka.media.TimeRangesUtils.bufferStart(
  662.         this.getBuffered_(contentType));
  663.   }
  665.   /**
  666.    * Gets the last timestamp in buffer for the given content type.
  667.    *
  668.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  669.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  670.    */
  671.   bufferEnd(contentType) {
  672.     if (!Object.keys(this.sourceBuffers_).length) {
  673.       return null;
  674.     }
  675.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  676.     if (contentType == ContentType.TEXT) {
  677.       return this.textEngine_.bufferEnd();
  678.     }
  679.     return shaka.media.TimeRangesUtils.bufferEnd(
  680.         this.getBuffered_(contentType));
  681.   }
  683.   /**
  684.    * Determines if the given time is inside the buffered range of the given
  685.    * content type.
  686.    *
  687.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  688.    * @param {number} time Playhead time
  689.    * @return {boolean}
  690.    */
  691.   isBuffered(contentType, time) {
  692.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  693.     if (contentType == ContentType.TEXT) {
  694.       return this.textEngine_.isBuffered(time);
  695.     } else {
  696.       const buffered = this.getBuffered_(contentType);
  697.       return shaka.media.TimeRangesUtils.isBuffered(buffered, time);
  698.     }
  699.   }
  701.   /**
  702.    * Computes how far ahead of the given timestamp is buffered for the given
  703.    * content type.
  704.    *
  705.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  706.    * @param {number} time
  707.    * @return {number} The amount of time buffered ahead in seconds.
  708.    */
  709.   bufferedAheadOf(contentType, time) {
  710.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  711.     if (contentType == ContentType.TEXT) {
  712.       return this.textEngine_.bufferedAheadOf(time);
  713.     } else {
  714.       const buffered = this.getBuffered_(contentType);
  715.       return shaka.media.TimeRangesUtils.bufferedAheadOf(buffered, time);
  716.     }
  717.   }
  719.   /**
  720.    * Returns info about what is currently buffered.
  721.    * @return {shaka.extern.BufferedInfo}
  722.    */
  723.   getBufferedInfo() {
  724.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  725.     const TimeRangesUtils = shaka.media.TimeRangesUtils;
  727.     const info = {
  728.       total: this.reloadingMediaSource_ ? [] :
  729.         TimeRangesUtils.getBufferedInfo(this.video_.buffered),
  730.       audio:
  731.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.AUDIO)),
  732.       video:
  733.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.VIDEO)),
  734.       text: [],
  735.     };
  737.     if (this.textEngine_) {
  738.       const start = this.textEngine_.bufferStart();
  739.       const end = this.textEngine_.bufferEnd();
  741.       if (start != null && end != null) {
  742.         info.text.push({start: start, end: end});
  743.       }
  744.     }
  745.     return info;
  746.   }
  748.   /**
  749.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  750.    * @return {TimeRanges} The buffered ranges for the given content type, or
  751.    *   null if the buffered ranges could not be obtained.
  752.    * @private
  753.    */
  754.   getBuffered_(contentType) {
  755.     if (this.reloadingMediaSource_) {
  756.       return null;
  757.     }
  758.     try {
  759.       return this.sourceBuffers_[contentType].buffered;
  760.     } catch (exception) {
  761.       if (contentType in this.sourceBuffers_) {
  762.         // Note: previous MediaSource errors may cause access to |buffered| to
  763.         // throw.
  764.         shaka.log.error('failed to get buffered range for ' + contentType,
  765.             exception);
  766.       }
  767.       return null;
  768.     }
  769.   }
  771.   /**
  772.    * Create a new closed caption parser. This will ONLY be replaced by tests as
  773.    * a way to inject fake closed caption parser instances.
  774.    *
  775.    * @param {string} mimeType
  776.    * @return {!shaka.media.IClosedCaptionParser}
  777.    */
  778.   getCaptionParser(mimeType) {
  779.     return new shaka.media.ClosedCaptionParser(mimeType);
  780.   }
  782.   /**
  783.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  784.    * @param {!BufferSource} data
  785.    * @param {?shaka.media.SegmentReference} reference The segment reference
  786.    *   we are appending, or null for init segments
  787.    * @param {!string} mimeType
  788.    * @return {{timestamp: ?number, metadata: !Array.<shaka.extern.ID3Metadata>}}
  789.    * @private
  790.    */
  791.   getTimestampAndDispatchMetadata_(contentType, data, reference, mimeType) {
  792.     let timestamp = null;
  793.     let metadata = [];
  795.     const uint8ArrayData = shaka.util.BufferUtils.toUint8(data);
  796.     if (shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType)) {
  797.       const frames = shaka.util.Id3Utils.getID3Frames(uint8ArrayData);
  798.       if (frames.length && reference) {
  799.         const metadataTimestamp = frames.find((frame) => {
  800.           return frame.description ===
  801.               'com.apple.streaming.transportStreamTimestamp';
  802.         });
  803.         if (metadataTimestamp) {
  804.           timestamp = Math.round(metadataTimestamp.data) / 1000;
  805.         }
  806.         /** @private {shaka.extern.ID3Metadata} */
  807.         const id3Metadata = {
  808.           cueTime: reference.startTime,
  809.           data: uint8ArrayData,
  810.           frames: frames,
  811.           dts: reference.startTime,
  812.           pts: reference.startTime,
  813.         };
  814.         this.playerInterface_.onMetadata(
  815.             [id3Metadata], /* offset= */ 0, reference.endTime);
  816.       }
  817.     } else if (mimeType.includes('/mp4') &&
  818.         reference && reference.timestampOffset == 0 &&
  819.         reference.initSegmentReference &&
  820.         reference.initSegmentReference.timescale) {
  821.       const timescale = reference.initSegmentReference.timescale;
  822.       if (!isNaN(timescale)) {
  823.         const Mp4Parser = shaka.util.Mp4Parser;
  824.         let startTime = 0;
  825.         let parsedMedia = false;
  826.         new Mp4Parser()
  827.             .box('moof', Mp4Parser.children)
  828.             .box('traf', Mp4Parser.children)
  829.             .fullBox('tfdt', (box) => {
  830.               goog.asserts.assert(
  831.                   box.version == 0 || box.version == 1,
  832.                   'TFDT version can only be 0 or 1');
  833.               const parsed = shaka.util.Mp4BoxParsers.parseTFDTInaccurate(
  834.                   box.reader, box.version);
  835.               startTime = parsed.baseMediaDecodeTime / timescale;
  836.               parsedMedia = true;
  837.               box.parser.stop();
  838.             }).parse(data, /* partialOkay= */ true);
  839.         if (parsedMedia) {
  840.           timestamp = startTime;
  841.         }
  842.       }
  843.     } else if (!mimeType.includes('/mp4') && !mimeType.includes('/webm') &&
  844.         shaka.util.TsParser.probe(uint8ArrayData)) {
  845.       if (!this.tsParsers_[contentType]) {
  846.         this.tsParsers_[contentType] = new shaka.util.TsParser();
  847.       } else {
  848.         this.tsParsers_[contentType].clearData();
  849.       }
  850.       const tsParser = this.tsParsers_[contentType].parse(uint8ArrayData);
  851.       const startTime = tsParser.getStartTime(contentType);
  852.       if (startTime != null) {
  853.         timestamp = startTime;
  854.       }
  855.       metadata = tsParser.getMetadata();
  856.     }
  857.     return {timestamp, metadata};
  858.   }
  860.   /**
  861.    * Enqueue an operation to append data to the SourceBuffer.
  862.    * Start and end times are needed for TextEngine, but not for MediaSource.
  863.    * Start and end times may be null for initialization segments; if present
  864.    * they are relative to the presentation timeline.
  865.    *
  866.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  867.    * @param {!BufferSource} data
  868.    * @param {?shaka.media.SegmentReference} reference The segment reference
  869.    *   we are appending, or null for init segments
  870.    * @param {shaka.extern.Stream} stream
  871.    * @param {?boolean} hasClosedCaptions True if the buffer contains CEA closed
  872.    *   captions
  873.    * @param {boolean=} seeked True if we just seeked
  874.    * @param {boolean=} adaptation True if we just automatically switched active
  875.    *   variant(s).
  876.    * @param {boolean=} isChunkedData True if we add to the buffer from the
  877.    *   partial read of the segment.
  878.    * @return {!Promise}
  879.    */
  880.   async appendBuffer(
  881.       contentType, data, reference, stream, hasClosedCaptions, seeked = false,
  882.       adaptation = false, isChunkedData = false, fromSplit = false) {
  883.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  885.     if (contentType == ContentType.TEXT) {
  886.       if (this.manifestType_ == shaka.media.ManifestParser.HLS) {
  887.         // This won't be known until the first video segment is appended.
  888.         const offset = await this.textSequenceModeOffset_;
  889.         this.textEngine_.setTimestampOffset(offset);
  890.       }
  891.       await this.textEngine_.appendBuffer(
  892.           data,
  893.           reference ? reference.startTime : null,
  894.           reference ? reference.endTime : null,
  895.           reference ? reference.getUris()[0] : null);
  896.       return;
  897.     }
  899.     if (!fromSplit && this.needSplitMuxedContent_) {
  900.       await this.appendBuffer(ContentType.AUDIO, data, reference, stream,
  901.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  902.           /* fromSplit= */ true);
  903.       await this.appendBuffer(ContentType.VIDEO, data, reference, stream,
  904.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  905.           /* fromSplit= */ true);
  906.       return;
  907.     }
  909.     if (!this.sourceBuffers_[contentType]) {
  910.       shaka.log.warning('Attempted to restore a non-existent source buffer');
  911.       return;
  912.     }
  914.     let timestampOffset = this.sourceBuffers_[contentType].timestampOffset;
  916.     let mimeType = this.sourceBufferTypes_[contentType];
  917.     if (this.transmuxers_[contentType]) {
  918.       mimeType = this.transmuxers_[contentType].getOriginalMimeType();
  919.     }
  920.     if (reference) {
  921.       const {timestamp, metadata} = this.getTimestampAndDispatchMetadata_(
  922.           contentType, data, reference, mimeType);
  923.       if (timestamp != null) {
  924.         if (this.firstVideoTimestamp_ == null &&
  925.             contentType == ContentType.VIDEO) {
  926.           this.firstVideoTimestamp_ = timestamp;
  927.           this.firstVideoReferenceStartTime_ = reference.startTime;
  928.           if (this.firstAudioTimestamp_ != null) {
  929.             let compensation = 0;
  930.             // Only apply compensation if video and audio segment startTime
  931.             // match, to avoid introducing sync issues.
  932.             if (this.firstVideoReferenceStartTime_ ==
  933.                 this.firstAudioReferenceStartTime_) {
  934.               compensation =
  935.                   this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  936.             }
  937.             this.audioCompensation_.resolve(compensation);
  938.           }
  939.         }
  940.         if (this.firstAudioTimestamp_ == null &&
  941.             contentType == ContentType.AUDIO) {
  942.           this.firstAudioTimestamp_ = timestamp;
  943.           this.firstAudioReferenceStartTime_ = reference.startTime;
  944.           if (this.firstVideoTimestamp_ != null) {
  945.             let compensation = 0;
  946.             // Only apply compensation if video and audio segment startTime
  947.             // match, to avoid introducing sync issues.
  948.             if (this.firstVideoReferenceStartTime_ ==
  949.                 this.firstAudioReferenceStartTime_) {
  950.               compensation =
  951.                   this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  952.             }
  953.             this.audioCompensation_.resolve(compensation);
  954.           }
  955.         }
  956.         const calculatedTimestampOffset = reference.startTime - timestamp;
  957.         const timestampOffsetDifference =
  958.             Math.abs(timestampOffset - calculatedTimestampOffset);
  959.         if ((timestampOffsetDifference >= 0.001 || seeked || adaptation) &&
  960.             (!isChunkedData || calculatedTimestampOffset > 0 ||
  961.             !timestampOffset)) {
  962.           timestampOffset = calculatedTimestampOffset;
  963.           if (this.attemptTimestampOffsetCalculation_) {
  964.             this.enqueueOperation_(
  965.                 contentType,
  966.                 () => this.abort_(contentType),
  967.                 null);
  968.             this.enqueueOperation_(
  969.                 contentType,
  970.                 () => this.setTimestampOffset_(contentType, timestampOffset),
  971.                 null);
  972.           }
  973.         }
  974.         // Timestamps can only be reliably extracted from video, not audio.
  975.         // Packed audio formats do not have internal timestamps at all.
  976.         // Prefer video for this when available.
  977.         const isBestSourceBufferForTimestamps =
  978.             contentType == ContentType.VIDEO ||
  979.             !(ContentType.VIDEO in this.sourceBuffers_);
  980.         if (isBestSourceBufferForTimestamps) {
  981.           this.textSequenceModeOffset_.resolve(timestampOffset);
  982.         }
  983.       }
  984.       if (metadata.length) {
  985.         this.playerInterface_.onMetadata(metadata, timestampOffset,
  986.             reference ? reference.endTime : null);
  987.       }
  988.     }
  989.     if (hasClosedCaptions && contentType == ContentType.VIDEO) {
  990.       if (!this.textEngine_) {
  991.         this.reinitText(shaka.util.MimeUtils.CEA608_CLOSED_CAPTION_MIMETYPE,
  992.             this.sequenceMode_, /* external= */ false);
  993.       }
  994.       if (!this.captionParser_) {
  995.         const basicType = mimeType.split(';', 1)[0];
  996.         this.captionParser_ = this.getCaptionParser(basicType);
  997.       }
  998.       // If it is the init segment for closed captions, initialize the closed
  999.       // caption parser.
  1000.       if (!reference) {
  1001.         this.captionParser_.init(data, adaptation);
  1002.       } else {
  1003.         const closedCaptions = this.captionParser_.parseFrom(data);
  1004.         if (closedCaptions.length) {
  1005.           this.textEngine_.storeAndAppendClosedCaptions(
  1006.               closedCaptions,
  1007.               reference.startTime,
  1008.               reference.endTime,
  1009.               timestampOffset);
  1010.         }
  1011.       }
  1012.     }
  1014.     if (this.transmuxers_[contentType]) {
  1015.       data = await this.transmuxers_[contentType].transmux(
  1016.           data, stream, reference, this.mediaSource_.duration, contentType);
  1017.     }
  1019.     data = this.workAroundBrokenPlatforms_(
  1020.         data, reference ? reference.startTime : null, contentType,
  1021.         reference ? reference.getUris()[0] : null);
  1023.     if (reference && this.sequenceMode_ && contentType != ContentType.TEXT) {
  1024.       // In sequence mode, for non-text streams, if we just cleared the buffer
  1025.       // and are either performing an unbuffered seek or handling an automatic
  1026.       // adaptation, we need to set a new timestampOffset on the sourceBuffer.
  1027.       if (seeked || adaptation) {
  1028.         let timestampOffset = reference.startTime;
  1029.         // Audio and video may not be aligned, so we will compensate for audio
  1030.         // if necessary.
  1031.         if (this.manifestType_ == shaka.media.ManifestParser.HLS &&
  1032.             !this.needSplitMuxedContent_ &&
  1033.             contentType == ContentType.AUDIO &&
  1034.             this.sourceBuffers_[ContentType.VIDEO]) {
  1035.           const compensation = await this.audioCompensation_;
  1036.           // Only apply compensation if the difference is greater than 100ms
  1037.           if (Math.abs(compensation) > 0.1) {
  1038.             timestampOffset -= compensation;
  1039.           }
  1040.         }
  1041.         // The logic to call abort() before setting the timestampOffset is
  1042.         // extended during unbuffered seeks or automatic adaptations; it is
  1043.         // possible for the append state to be PARSING_MEDIA_SEGMENT from the
  1044.         // previous SourceBuffer#appendBuffer() call.
  1045.         this.enqueueOperation_(
  1046.             contentType,
  1047.             () => this.abort_(contentType),
  1048.             null);
  1049.         this.enqueueOperation_(
  1050.             contentType,
  1051.             () => this.setTimestampOffset_(contentType, timestampOffset),
  1052.             null);
  1053.       }
  1054.     }
  1056.     let bufferedBefore = null;
  1058.     await this.enqueueOperation_(contentType, () => {
  1059.       if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1060.         bufferedBefore = this.getBuffered_(contentType);
  1061.       }
  1062.       this.append_(contentType, data, timestampOffset);
  1063.     }, reference ? reference.getUris()[0] : null);
  1065.     if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1066.       const bufferedAfter = this.getBuffered_(contentType);
  1067.       const newBuffered = shaka.media.TimeRangesUtils.computeAddedRange(
  1068.           bufferedBefore, bufferedAfter);
  1069.       if (newBuffered) {
  1070.         const segmentDuration = reference.endTime - reference.startTime;
  1071.         const timeAdded = newBuffered.end - newBuffered.start;
  1072.         // Check end times instead of start times.  We may be overwriting a
  1073.         // buffer and only the end changes, and that would be fine.
  1074.         // Also, exclude tiny segments.  Sometimes alignment segments as small
  1075.         // as 33ms are seen in Google DAI content.  For such tiny segments,
  1076.         // half a segment duration would be no issue.
  1077.         const offset = Math.abs(newBuffered.end - reference.endTime);
  1078.         if (segmentDuration > 0.100 && (offset > segmentDuration / 2 ||
  1079.             Math.abs(segmentDuration - timeAdded) > 0.030)) {
  1080.           shaka.log.error('Possible encoding problem detected!',
  1081.               'Unexpected buffered range for reference', reference,
  1082.               'from URIs', reference.getUris(),
  1083.               'should be', {start: reference.startTime, end: reference.endTime},
  1084.               'but got', newBuffered);
  1085.         }
  1086.       }
  1087.     }
  1088.   }
  1090.   /**
  1091.    * Set the selected closed captions Id and language.
  1092.    *
  1093.    * @param {string} id
  1094.    */
  1095.   setSelectedClosedCaptionId(id) {
  1096.     const VIDEO = shaka.util.ManifestParserUtils.ContentType.VIDEO;
  1097.     const videoBufferEndTime = this.bufferEnd(VIDEO) || 0;
  1098.     this.textEngine_.setSelectedClosedCaptionId(id, videoBufferEndTime);
  1099.   }
  1101.   /** Disable embedded closed captions. */
  1102.   clearSelectedClosedCaptionId() {
  1103.     if (this.textEngine_) {
  1104.       this.textEngine_.setSelectedClosedCaptionId('', 0);
  1105.     }
  1106.   }
  1108.   /**
  1109.    * Enqueue an operation to remove data from the SourceBuffer.
  1110.    *
  1111.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1112.    * @param {number} startTime relative to the start of the presentation
  1113.    * @param {number} endTime relative to the start of the presentation
  1114.    * @return {!Promise}
  1115.    */
  1116.   async remove(contentType, startTime, endTime) {
  1117.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1118.     if (contentType == ContentType.TEXT) {
  1119.       await this.textEngine_.remove(startTime, endTime);
  1120.     } else {
  1121.       await this.enqueueOperation_(
  1122.           contentType,
  1123.           () => this.remove_(contentType, startTime, endTime),
  1124.           null);
  1125.       if (this.needSplitMuxedContent_) {
  1126.         await this.enqueueOperation_(
  1127.             ContentType.AUDIO,
  1128.             () => this.remove_(ContentType.AUDIO, startTime, endTime),
  1129.             null);
  1130.       }
  1131.     }
  1132.   }
  1134.   /**
  1135.    * Enqueue an operation to clear the SourceBuffer.
  1136.    *
  1137.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1138.    * @return {!Promise}
  1139.    */
  1140.   async clear(contentType) {
  1141.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1142.     if (contentType == ContentType.TEXT) {
  1143.       if (!this.textEngine_) {
  1144.         return;
  1145.       }
  1146.       await this.textEngine_.remove(0, Infinity);
  1147.     } else {
  1148.       // Note that not all platforms allow clearing to Infinity.
  1149.       await this.enqueueOperation_(
  1150.           contentType,
  1151.           () => this.remove_(contentType, 0, this.mediaSource_.duration),
  1152.           null);
  1153.       if (this.needSplitMuxedContent_) {
  1154.         await this.enqueueOperation_(
  1155.             ContentType.AUDIO,
  1156.             () => this.remove_(
  1157.                 ContentType.AUDIO, 0, this.mediaSource_.duration),
  1158.             null);
  1159.       }
  1160.     }
  1161.   }
  1163.   /**
  1164.    * Fully reset the state of the caption parser owned by MediaSourceEngine.
  1165.    */
  1166.   resetCaptionParser() {
  1167.     if (this.captionParser_) {
  1168.       this.captionParser_.reset();
  1169.     }
  1170.   }
  1172.   /**
  1173.    * Enqueue an operation to flush the SourceBuffer.
  1174.    * This is a workaround for what we believe is a Chromecast bug.
  1175.    *
  1176.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1177.    * @return {!Promise}
  1178.    */
  1179.   async flush(contentType) {
  1180.     // Flush the pipeline.  Necessary on Chromecast, even though we have removed
  1181.     // everything.
  1182.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1183.     if (contentType == ContentType.TEXT) {
  1184.       // Nothing to flush for text.
  1185.       return;
  1186.     }
  1187.     await this.enqueueOperation_(
  1188.         contentType,
  1189.         () => this.flush_(contentType),
  1190.         null);
  1191.     if (this.needSplitMuxedContent_) {
  1192.       await this.enqueueOperation_(
  1193.           ContentType.AUDIO,
  1194.           () => this.flush_(ContentType.AUDIO),
  1195.           null);
  1196.     }
  1197.   }
  1199.   /**
  1200.    * Sets the timestamp offset and append window end for the given content type.
  1201.    *
  1202.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1203.    * @param {number} timestampOffset The timestamp offset.  Segments which start
  1204.    *   at time t will be inserted at time t + timestampOffset instead.  This
  1205.    *   value does not affect segments which have already been inserted.
  1206.    * @param {number} appendWindowStart The timestamp to set the append window
  1207.    *   start to.  For future appends, frames/samples with timestamps less than
  1208.    *   this value will be dropped.
  1209.    * @param {number} appendWindowEnd The timestamp to set the append window end
  1210.    *   to.  For future appends, frames/samples with timestamps greater than this
  1211.    *   value will be dropped.
  1212.    * @param {boolean} ignoreTimestampOffset  If true, the timestampOffset will
  1213.    *   not be applied in this step.
  1214.    * @param {string} mimeType
  1215.    * @param {string} codecs
  1216.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1217.    *               shaka.extern.Stream>} streamsByType
  1218.    *   A map of content types to streams.  All streams must be supported
  1219.    *   according to MediaSourceEngine.isStreamSupported.
  1220.    *
  1221.    * @return {!Promise}
  1222.    */
  1223.   async setStreamProperties(
  1224.       contentType, timestampOffset, appendWindowStart, appendWindowEnd,
  1225.       ignoreTimestampOffset, mimeType, codecs, streamsByType) {
  1226.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1227.     if (contentType == ContentType.TEXT) {
  1228.       if (!ignoreTimestampOffset) {
  1229.         this.textEngine_.setTimestampOffset(timestampOffset);
  1230.       }
  1231.       this.textEngine_.setAppendWindow(appendWindowStart, appendWindowEnd);
  1232.       return;
  1233.     }
  1234.     const operations = [];
  1236.     const hasChangedCodecs = await this.codecSwitchIfNecessary_(
  1237.         contentType, mimeType, codecs, streamsByType);
  1239.     if (!hasChangedCodecs) {
  1240.       // Queue an abort() to help MSE splice together overlapping segments.
  1241.       // We set appendWindowEnd when we change periods in DASH content, and the
  1242.       // period transition may result in overlap.
  1243.       //
  1244.       // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1245.       // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1246.       // timestamp offset.  By calling abort(), we reset the state so we can
  1247.       // set it.
  1248.       operations.push(this.enqueueOperation_(
  1249.           contentType,
  1250.           () => this.abort_(contentType),
  1251.           null));
  1252.       if (this.needSplitMuxedContent_) {
  1253.         operations.push(this.enqueueOperation_(
  1254.             ContentType.AUDIO,
  1255.             () => this.abort_(ContentType.AUDIO),
  1256.             null));
  1257.       }
  1258.     }
  1259.     if (!ignoreTimestampOffset) {
  1260.       operations.push(this.enqueueOperation_(
  1261.           contentType,
  1262.           () => this.setTimestampOffset_(contentType, timestampOffset),
  1263.           null));
  1264.       if (this.needSplitMuxedContent_) {
  1265.         operations.push(this.enqueueOperation_(
  1266.             ContentType.AUDIO,
  1267.             () => this.setTimestampOffset_(
  1268.                 ContentType.AUDIO, timestampOffset),
  1269.             null));
  1270.       }
  1271.     }
  1272.     operations.push(this.enqueueOperation_(
  1273.         contentType,
  1274.         () => this.setAppendWindow_(
  1275.             contentType, appendWindowStart, appendWindowEnd),
  1276.         null));
  1277.     if (this.needSplitMuxedContent_) {
  1278.       operations.push(this.enqueueOperation_(
  1279.           ContentType.AUDIO,
  1280.           () => this.setAppendWindow_(
  1281.               ContentType.AUDIO, appendWindowStart, appendWindowEnd),
  1282.           null));
  1283.     }
  1285.     await Promise.all(operations);
  1286.   }
  1288.   /**
  1289.    * Adjust timestamp offset to maintain AV sync across discontinuities.
  1290.    *
  1291.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1292.    * @param {number} timestampOffset
  1293.    * @return {!Promise}
  1294.    */
  1295.   async resync(contentType, timestampOffset) {
  1296.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1298.     if (contentType == ContentType.TEXT) {
  1299.       // This operation is for audio and video only.
  1300.       return;
  1301.     }
  1303.     // Reset the promise in case the timestamp offset changed during
  1304.     // a period/discontinuity transition.
  1305.     if (contentType == ContentType.VIDEO) {
  1306.       this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
  1307.     }
  1309.     if (!this.sequenceMode_) {
  1310.       return;
  1311.     }
  1313.     // Queue an abort() to help MSE splice together overlapping segments.
  1314.     // We set appendWindowEnd when we change periods in DASH content, and the
  1315.     // period transition may result in overlap.
  1316.     //
  1317.     // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1318.     // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1319.     // timestamp offset.  By calling abort(), we reset the state so we can
  1320.     // set it.
  1321.     this.enqueueOperation_(
  1322.         contentType,
  1323.         () => this.abort_(contentType),
  1324.         null);
  1325.     if (this.needSplitMuxedContent_) {
  1326.       this.enqueueOperation_(
  1327.           ContentType.AUDIO,
  1328.           () => this.abort_(ContentType.AUDIO),
  1329.           null);
  1330.     }
  1331.     await this.enqueueOperation_(
  1332.         contentType,
  1333.         () => this.setTimestampOffset_(contentType, timestampOffset),
  1334.         null);
  1335.     if (this.needSplitMuxedContent_) {
  1336.       await this.enqueueOperation_(
  1337.           ContentType.AUDIO,
  1338.           () => this.setTimestampOffset_(ContentType.AUDIO, timestampOffset),
  1339.           null);
  1340.     }
  1341.   }
  1343.   /**
  1344.    * @param {string=} reason Valid reasons are 'network' and 'decode'.
  1345.    * @return {!Promise}
  1346.    * @see http://w3c.github.io/media-source/#idl-def-EndOfStreamError
  1347.    */
  1348.   async endOfStream(reason) {
  1349.     await this.enqueueBlockingOperation_(() => {
  1350.       // If endOfStream() has already been called on the media source,
  1351.       // don't call it again. Also do not call if readyState is
  1352.       // 'closed' (not attached to video element) since it is not a
  1353.       // valid operation.
  1354.       if (this.ended() || this.mediaSource_.readyState === 'closed') {
  1355.         return;
  1356.       }
  1357.       // Tizen won't let us pass undefined, but it will let us omit the
  1358.       // argument.
  1359.       if (reason) {
  1360.         this.mediaSource_.endOfStream(reason);
  1361.       } else {
  1362.         this.mediaSource_.endOfStream();
  1363.       }
  1364.     });
  1365.   }
  1367.   /**
  1368.    * @param {number} duration
  1369.    * @return {!Promise}
  1370.    */
  1371.   async setDuration(duration) {
  1372.     await this.enqueueBlockingOperation_(() => {
  1373.       // Reducing the duration causes the MSE removal algorithm to run, which
  1374.       // triggers an 'updateend' event to fire.  To handle this scenario, we
  1375.       // have to insert a dummy operation into the beginning of each queue,
  1376.       // which the 'updateend' handler will remove.
  1377.       if (duration < this.mediaSource_.duration) {
  1378.         for (const contentType in this.sourceBuffers_) {
  1379.           const dummyOperation = {
  1380.             start: () => {},
  1381.             p: new shaka.util.PublicPromise(),
  1382.             uri: null,
  1383.           };
  1384.           this.queues_[contentType].unshift(dummyOperation);
  1385.         }
  1386.       }
  1388.       this.mediaSource_.duration = duration;
  1389.       this.lastDuration_ = duration;
  1390.     });
  1391.   }
  1393.   /**
  1394.    * Get the current MediaSource duration.
  1395.    *
  1396.    * @return {number}
  1397.    */
  1398.   getDuration() {
  1399.     return this.mediaSource_.duration;
  1400.   }
  1402.   /**
  1403.    * Append data to the SourceBuffer.
  1404.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1405.    * @param {BufferSource} data
  1406.    * @param {number} timestampOffset
  1407.    * @private
  1408.    */
  1409.   append_(contentType, data, timestampOffset) {
  1410.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1412.     // Append only video data to the LCEVC Dec.
  1413.     if (contentType == ContentType.VIDEO && this.lcevcDec_) {
  1414.       // Append video buffers to the LCEVC Dec for parsing and storing
  1415.       // of LCEVC data.
  1416.       this.lcevcDec_.appendBuffer(data, timestampOffset);
  1417.     }
  1419.     // This will trigger an 'updateend' event.
  1420.     this.sourceBuffers_[contentType].appendBuffer(data);
  1421.   }
  1423.   /**
  1424.    * Remove data from the SourceBuffer.
  1425.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1426.    * @param {number} startTime relative to the start of the presentation
  1427.    * @param {number} endTime relative to the start of the presentation
  1428.    * @private
  1429.    */
  1430.   remove_(contentType, startTime, endTime) {
  1431.     if (endTime <= startTime) {
  1432.       // Ignore removal of inverted or empty ranges.
  1433.       // Fake 'updateend' event to resolve the operation.
  1434.       this.onUpdateEnd_(contentType);
  1435.       return;
  1436.     }
  1438.     // This will trigger an 'updateend' event.
  1439.     this.sourceBuffers_[contentType].remove(startTime, endTime);
  1440.   }
  1442.   /**
  1443.    * Call abort() on the SourceBuffer.
  1444.    * This resets MSE's last_decode_timestamp on all track buffers, which should
  1445.    * trigger the splicing logic for overlapping segments.
  1446.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1447.    * @private
  1448.    */
  1449.   abort_(contentType) {
  1450.     // Save the append window, which is reset on abort().
  1451.     const appendWindowStart =
  1452.         this.sourceBuffers_[contentType].appendWindowStart;
  1453.     const appendWindowEnd = this.sourceBuffers_[contentType].appendWindowEnd;
  1455.     // This will not trigger an 'updateend' event, since nothing is happening.
  1456.     // This is only to reset MSE internals, not to abort an actual operation.
  1457.     this.sourceBuffers_[contentType].abort();
  1459.     // Restore the append window.
  1460.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1461.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1463.     // Fake an 'updateend' event to resolve the operation.
  1464.     this.onUpdateEnd_(contentType);
  1465.   }
  1467.   /**
  1468.    * Nudge the playhead to force the media pipeline to be flushed.
  1469.    * This seems to be necessary on Chromecast to get new content to replace old
  1470.    * content.
  1471.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1472.    * @private
  1473.    */
  1474.   flush_(contentType) {
  1475.     // Never use flush_ if there's data.  It causes a hiccup in playback.
  1476.     goog.asserts.assert(
  1477.         this.video_.buffered.length == 0, 'MediaSourceEngine.flush_ should ' +
  1478.         'only be used after clearing all data!');
  1480.     // Seeking forces the pipeline to be flushed.
  1481.     this.video_.currentTime -= 0.001;
  1483.     // Fake an 'updateend' event to resolve the operation.
  1484.     this.onUpdateEnd_(contentType);
  1485.   }
  1487.   /**
  1488.    * Set the SourceBuffer's timestamp offset.
  1489.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1490.    * @param {number} timestampOffset
  1491.    * @private
  1492.    */
  1493.   setTimestampOffset_(contentType, timestampOffset) {
  1494.     // Work around for
  1495.     // https://github.com/shaka-project/shaka-player/issues/1281:
  1496.     // TODO(https://bit.ly/2ttKiBU): follow up when this is fixed in Edge
  1497.     if (timestampOffset < 0) {
  1498.       // Try to prevent rounding errors in Edge from removing the first
  1499.       // keyframe.
  1500.       timestampOffset += 0.001;
  1501.     }
  1503.     this.sourceBuffers_[contentType].timestampOffset = timestampOffset;
  1505.     // Fake an 'updateend' event to resolve the operation.
  1506.     this.onUpdateEnd_(contentType);
  1507.   }
  1509.   /**
  1510.    * Set the SourceBuffer's append window end.
  1511.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1512.    * @param {number} appendWindowStart
  1513.    * @param {number} appendWindowEnd
  1514.    * @private
  1515.    */
  1516.   setAppendWindow_(contentType, appendWindowStart, appendWindowEnd) {
  1517.     // You can't set start > end, so first set start to 0, then set the new
  1518.     // end, then set the new start.  That way, there are no intermediate
  1519.     // states which are invalid.
  1520.     this.sourceBuffers_[contentType].appendWindowStart = 0;
  1521.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1522.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1524.     // Fake an 'updateend' event to resolve the operation.
  1525.     this.onUpdateEnd_(contentType);
  1526.   }
  1528.   /**
  1529.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1530.    * @private
  1531.    */
  1532.   onError_(contentType) {
  1533.     const operation = this.queues_[contentType][0];
  1534.     goog.asserts.assert(operation, 'Spurious error event!');
  1535.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1536.         'SourceBuffer should not be updating on error!');
  1537.     const code = this.video_.error ? this.video_.error.code : 0;
  1538.     operation.p.reject(new shaka.util.Error(
  1539.         shaka.util.Error.Severity.CRITICAL,
  1540.         shaka.util.Error.Category.MEDIA,
  1541.         shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_FAILED,
  1542.         code, operation.uri));
  1543.     // Do not pop from queue.  An 'updateend' event will fire next, and to
  1544.     // avoid synchronizing these two event handlers, we will allow that one to
  1545.     // pop from the queue as normal.  Note that because the operation has
  1546.     // already been rejected, the call to resolve() in the 'updateend' handler
  1547.     // will have no effect.
  1548.   }
  1550.   /**
  1551.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1552.    * @private
  1553.    */
  1554.   onUpdateEnd_(contentType) {
  1555.     if (this.reloadingMediaSource_) {
  1556.       return;
  1557.     }
  1558.     const operation = this.queues_[contentType][0];
  1559.     goog.asserts.assert(operation, 'Spurious updateend event!');
  1560.     if (!operation) {
  1561.       return;
  1562.     }
  1563.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1564.         'SourceBuffer should not be updating on updateend!');
  1565.     operation.p.resolve();
  1566.     this.popFromQueue_(contentType);
  1567.   }
  1569.   /**
  1570.    * Enqueue an operation and start it if appropriate.
  1571.    *
  1572.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1573.    * @param {function()} start
  1574.    * @param {?string} uri
  1575.    * @return {!Promise}
  1576.    * @private
  1577.    */
  1578.   enqueueOperation_(contentType, start, uri) {
  1579.     this.destroyer_.ensureNotDestroyed();
  1580.     const operation = {
  1581.       start: start,
  1582.       p: new shaka.util.PublicPromise(),
  1583.       uri,
  1584.     };
  1585.     this.queues_[contentType].push(operation);
  1587.     if (this.queues_[contentType].length == 1) {
  1588.       this.startOperation_(contentType);
  1589.     }
  1590.     return operation.p;
  1591.   }
  1593.   /**
  1594.    * Enqueue an operation which must block all other operations on all
  1595.    * SourceBuffers.
  1596.    *
  1597.    * @param {function():(Promise|undefined)} run
  1598.    * @return {!Promise}
  1599.    * @private
  1600.    */
  1601.   async enqueueBlockingOperation_(run) {
  1602.     this.destroyer_.ensureNotDestroyed();
  1604.     /** @type {!Array.<!shaka.util.PublicPromise>} */
  1605.     const allWaiters = [];
  1607.     // Enqueue a 'wait' operation onto each queue.
  1608.     // This operation signals its readiness when it starts.
  1609.     // When all wait operations are ready, the real operation takes place.
  1610.     for (const contentType in this.sourceBuffers_) {
  1611.       const ready = new shaka.util.PublicPromise();
  1612.       const operation = {
  1613.         start: () => ready.resolve(),
  1614.         p: ready,
  1615.         uri: null,
  1616.       };
  1618.       this.queues_[contentType].push(operation);
  1619.       allWaiters.push(ready);
  1621.       if (this.queues_[contentType].length == 1) {
  1622.         operation.start();
  1623.       }
  1624.     }
  1626.     // Return a Promise to the real operation, which waits to begin until
  1627.     // there are no other in-progress operations on any SourceBuffers.
  1628.     try {
  1629.       await Promise.all(allWaiters);
  1630.     } catch (error) {
  1631.       // One of the waiters failed, which means we've been destroyed.
  1632.       goog.asserts.assert(
  1633.           this.destroyer_.destroyed(), 'Should be destroyed by now');
  1634.       // We haven't popped from the queue.  Canceled waiters have been removed
  1635.       // by destroy.  What's left now should just be resolved waiters.  In
  1636.       // uncompiled mode, we will maintain good hygiene and make sure the
  1637.       // assert at the end of destroy passes.  In compiled mode, the queues
  1638.       // are wiped in destroy.
  1639.       if (goog.DEBUG) {
  1640.         for (const contentType in this.sourceBuffers_) {
  1641.           if (this.queues_[contentType].length) {
  1642.             goog.asserts.assert(
  1643.                 this.queues_[contentType].length == 1,
  1644.                 'Should be at most one item in queue!');
  1645.             goog.asserts.assert(
  1646.                 allWaiters.includes(this.queues_[contentType][0].p),
  1647.                 'The item in queue should be one of our waiters!');
  1648.             this.queues_[contentType].shift();
  1649.           }
  1650.         }
  1651.       }
  1652.       throw error;
  1653.     }
  1655.     if (goog.DEBUG) {
  1656.       // If we did it correctly, nothing is updating.
  1657.       for (const contentType in this.sourceBuffers_) {
  1658.         goog.asserts.assert(
  1659.             this.sourceBuffers_[contentType].updating == false,
  1660.             'SourceBuffers should not be updating after a blocking op!');
  1661.       }
  1662.     }
  1664.     // Run the real operation, which can be asynchronous.
  1665.     try {
  1666.       await run();
  1667.     } catch (exception) {
  1668.       throw new shaka.util.Error(
  1669.           shaka.util.Error.Severity.CRITICAL,
  1670.           shaka.util.Error.Category.MEDIA,
  1671.           shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1672.           exception,
  1673.           this.video_.error || 'No error in the media element',
  1674.           null);
  1675.     } finally {
  1676.       // Unblock the queues.
  1677.       for (const contentType in this.sourceBuffers_) {
  1678.         this.popFromQueue_(contentType);
  1679.       }
  1680.     }
  1681.   }
  1683.   /**
  1684.    * Pop from the front of the queue and start a new operation.
  1685.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1686.    * @private
  1687.    */
  1688.   popFromQueue_(contentType) {
  1689.     // Remove the in-progress operation, which is now complete.
  1690.     this.queues_[contentType].shift();
  1691.     this.startOperation_(contentType);
  1692.   }
  1694.   /**
  1695.    * Starts the next operation in the queue.
  1696.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1697.    * @private
  1698.    */
  1699.   startOperation_(contentType) {
  1700.     // Retrieve the next operation, if any, from the queue and start it.
  1701.     const next = this.queues_[contentType][0];
  1702.     if (next) {
  1703.       try {
  1704.         next.start();
  1705.       } catch (exception) {
  1706.         if (exception.name == 'QuotaExceededError') {
  1707.           next.p.reject(new shaka.util.Error(
  1708.               shaka.util.Error.Severity.CRITICAL,
  1709.               shaka.util.Error.Category.MEDIA,
  1710.               shaka.util.Error.Code.QUOTA_EXCEEDED_ERROR,
  1711.               contentType));
  1712.         } else {
  1713.           next.p.reject(new shaka.util.Error(
  1714.               shaka.util.Error.Severity.CRITICAL,
  1715.               shaka.util.Error.Category.MEDIA,
  1716.               shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1717.               exception,
  1718.               this.video_.error || 'No error in the media element',
  1719.               next.uri));
  1720.         }
  1721.         this.popFromQueue_(contentType);
  1722.       }
  1723.     }
  1724.   }
  1726.   /**
  1727.    * @return {!shaka.extern.TextDisplayer}
  1728.    */
  1729.   getTextDisplayer() {
  1730.     goog.asserts.assert(
  1731.         this.textDisplayer_,
  1732.         'TextDisplayer should only be null when this is destroyed');
  1734.     return this.textDisplayer_;
  1735.   }
  1737.   /**
  1738.    * @param {!shaka.extern.TextDisplayer} textDisplayer
  1739.    */
  1740.   setTextDisplayer(textDisplayer) {
  1741.     this.textDisplayer_ = textDisplayer;
  1742.     if (this.textEngine_) {
  1743.       this.textEngine_.setDisplayer(textDisplayer);
  1744.     }
  1745.   }
  1747.   /**
  1748.    * @param {boolean} segmentRelativeVttTiming
  1749.    */
  1750.   setSegmentRelativeVttTiming(segmentRelativeVttTiming) {
  1751.     this.segmentRelativeVttTiming_ = segmentRelativeVttTiming;
  1752.   }
  1754.   /**
  1755.    * Apply platform-specific transformations to this segment to work around
  1756.    * issues in the platform.
  1757.    *
  1758.    * @param {!BufferSource} segment
  1759.    * @param {?number} startTime
  1760.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1761.    * @param {?string} uri
  1762.    * @return {!BufferSource}
  1763.    * @private
  1764.    */
  1765.   workAroundBrokenPlatforms_(segment, startTime, contentType, uri) {
  1766.     const Platform = shaka.util.Platform;
  1768.     const isInitSegment = startTime == null;
  1769.     const encryptionExpected = this.expectedEncryption_[contentType];
  1770.     const keySystem = this.playerInterface_.getKeySystem();
  1772.     // If:
  1773.     //   1. the configuration tells to insert fake encryption,
  1774.     //   2. and this is an init segment,
  1775.     //   3. and encryption is expected,
  1776.     //   4. and the platform requires encryption in all init segments,
  1777.     //   5. and the content is MP4 (mimeType == "video/mp4" or "audio/mp4"),
  1778.     // then insert fake encryption metadata for init segments that lack it.
  1779.     // The MP4 requirement is because we can currently only do this
  1780.     // transformation on MP4 containers.
  1781.     // See: https://github.com/shaka-project/shaka-player/issues/2759
  1782.     if (this.config_.insertFakeEncryptionInInit &&
  1783.         isInitSegment &&
  1784.         encryptionExpected &&
  1785.         Platform.requiresEncryptionInfoInAllInitSegments(keySystem) &&
  1786.         shaka.util.MimeUtils.getContainerType(
  1787.             this.sourceBufferTypes_[contentType]) == 'mp4') {
  1788.       shaka.log.debug('Forcing fake encryption information in init segment.');
  1789.       segment = shaka.media.ContentWorkarounds.fakeEncryption(segment, uri);
  1790.     }
  1792.     return segment;
  1793.   }
  1795.   /**
  1796.    * Prepare the SourceBuffer to parse a potentially new type or codec.
  1797.    *
  1798.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1799.    * @param {string} mimeType
  1800.    * @param {?shaka.extern.Transmuxer} transmuxer
  1801.    * @private
  1802.    */
  1803.   change_(contentType, mimeType, transmuxer) {
  1804.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1805.     if (contentType === ContentType.TEXT) {
  1806.       shaka.log.debug(`Change not supported for ${contentType}`);
  1807.       return;
  1808.     }
  1809.     shaka.log.debug(
  1810.         `Change Type: ${this.sourceBufferTypes_[contentType]} -> ${mimeType}`);
  1811.     if (shaka.media.Capabilities.isChangeTypeSupported()) {
  1812.       if (this.transmuxers_[contentType]) {
  1813.         this.transmuxers_[contentType].destroy();
  1814.         delete this.transmuxers_[contentType];
  1815.       }
  1816.       if (transmuxer) {
  1817.         this.transmuxers_[contentType] = transmuxer;
  1818.       }
  1819.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  1820.       this.sourceBuffers_[contentType].changeType(type);
  1821.       this.sourceBufferTypes_[contentType] = mimeType;
  1822.     } else {
  1823.       shaka.log.debug('Change Type not supported');
  1824.     }
  1826.     // Fake an 'updateend' event to resolve the operation.
  1827.     this.onUpdateEnd_(contentType);
  1828.   }
  1830.   /**
  1831.    * Enqueue an operation to prepare the SourceBuffer to parse a potentially new
  1832.    * type or codec.
  1833.    *
  1834.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1835.    * @param {string} mimeType
  1836.    * @param {?shaka.extern.Transmuxer} transmuxer
  1837.    * @return {!Promise}
  1838.    */
  1839.   changeType(contentType, mimeType, transmuxer) {
  1840.     return this.enqueueOperation_(
  1841.         contentType,
  1842.         () => this.change_(contentType, mimeType, transmuxer),
  1843.         null);
  1844.   }
  1846.   /**
  1847.    * Returns the source buffer parameters
  1848.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1849.    * @return {?shaka.media.MediaSourceEngine.SourceBufferParams}
  1850.    * @private
  1851.    */
  1852.   getSourceBufferParams_(contentType) {
  1853.     if (!this.sourceBuffers_[contentType]) {
  1854.       return null;
  1855.     }
  1856.     return {
  1857.       timestampOffset: this.sourceBuffers_[contentType].timestampOffset,
  1858.       appendWindowStart: this.sourceBuffers_[contentType].appendWindowStart,
  1859.       appendWindowEnd: this.sourceBuffers_[contentType].appendWindowEnd,
  1860.     };
  1861.   }
  1863.   /**
  1864.    * Restore source buffer parameters
  1865.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1866.    * @param {?shaka.media.MediaSourceEngine.SourceBufferParams} params
  1867.    * @private
  1868.    */
  1869.   restoreSourceBufferParams_(contentType, params) {
  1870.     if (!params) {
  1871.       return;
  1872.     }
  1874.     if (!this.sourceBuffers_[contentType]) {
  1875.       shaka.log.warning('Attempted to restore a non-existent source buffer');
  1876.       return;
  1877.     }
  1879.     this.sourceBuffers_[contentType].timestampOffset =
  1880.       params.timestampOffset;
  1881.     // `end` needs to be set before `start`
  1882.     this.sourceBuffers_[contentType].appendWindowEnd =
  1883.       params.appendWindowEnd;
  1884.     this.sourceBuffers_[contentType].appendWindowStart =
  1885.       params.appendWindowStart;
  1886.   }
  1888.   /**
  1889.    * Resets the MediaSource and re-adds source buffers due to codec mismatch
  1890.    *
  1891.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1892.    *               shaka.extern.Stream>} streamsByType
  1893.    * @private
  1894.    */
  1895.   async reset_(streamsByType) {
  1896.     const Functional = shaka.util.Functional;
  1897.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1898.     this.reloadingMediaSource_ = true;
  1899.     this.needSplitMuxedContent_ = false;
  1900.     const currentTime = this.video_.currentTime;
  1902.     // When codec switching if the user is currently paused we don't want
  1903.     // to trigger a play when switching codec.
  1904.     // Playing can also end up in a paused state after a codec switch
  1905.     // so we need to remember the current states.
  1906.     const previousAutoPlayState = this.video_.autoplay;
  1907.     const previousPausedState = this.video_.paused;
  1908.     if (this.playbackHasBegun_) {
  1909.       // Only set autoplay to false if the video playback has already begun.
  1910.       // When a codec switch happens before playback has begun this can cause
  1911.       // autoplay not to work as expected.
  1912.       this.video_.autoplay = false;
  1913.     }
  1915.     try {
  1916.       this.eventManager_.removeAll();
  1918.       const cleanup = [];
  1919.       for (const contentType in this.transmuxers_) {
  1920.         cleanup.push(this.transmuxers_[contentType].destroy());
  1921.       }
  1922.       for (const contentType in this.queues_) {
  1923.         // Make a local copy of the queue and the first item.
  1924.         const q = this.queues_[contentType];
  1925.         const inProgress = q[0];
  1927.         // Drop everything else out of the original queue.
  1928.         this.queues_[contentType] = q.slice(0, 1);
  1930.         // We will wait for this item to complete/fail.
  1931.         if (inProgress) {
  1932.           cleanup.push(inProgress.p.catch(Functional.noop));
  1933.         }
  1935.         // The rest will be rejected silently if possible.
  1936.         for (const item of q.slice(1)) {
  1937.           item.p.reject(shaka.util.Destroyer.destroyedError());
  1938.         }
  1939.       }
  1940.       for (const contentType in this.sourceBuffers_) {
  1941.         const sourceBuffer = this.sourceBuffers_[contentType];
  1942.         try {
  1943.           this.mediaSource_.removeSourceBuffer(sourceBuffer);
  1944.         } catch (e) {}
  1945.       }
  1946.       await Promise.all(cleanup);
  1947.       this.transmuxers_ = {};
  1949.       const previousDuration = this.mediaSource_.duration;
  1950.       this.mediaSourceOpen_ = new shaka.util.PublicPromise();
  1951.       this.mediaSource_ = this.createMediaSource(this.mediaSourceOpen_);
  1952.       await this.mediaSourceOpen_;
  1953.       if (!isNaN(previousDuration) && previousDuration) {
  1954.         this.mediaSource_.duration = previousDuration;
  1955.       } else if (!isNaN(this.lastDuration_) && this.lastDuration_) {
  1956.         this.mediaSource_.duration = this.lastDuration_;
  1957.       }
  1959.       const sourceBufferAdded = new shaka.util.PublicPromise();
  1960.       const sourceBuffers =
  1961.         /** @type {EventTarget} */(this.mediaSource_.sourceBuffers);
  1963.       const totalOfBuffers = streamsByType.size;
  1964.       let numberOfSourceBufferAdded = 0;
  1965.       const onSourceBufferAdded = () => {
  1966.         numberOfSourceBufferAdded++;
  1967.         if (numberOfSourceBufferAdded === totalOfBuffers) {
  1968.           sourceBufferAdded.resolve();
  1969.           this.eventManager_.unlisten(sourceBuffers, 'addsourcebuffer',
  1970.               onSourceBufferAdded);
  1971.         }
  1972.       };
  1974.       this.eventManager_.listen(sourceBuffers, 'addsourcebuffer',
  1975.           onSourceBufferAdded);
  1977.       for (const contentType of streamsByType.keys()) {
  1978.         const previousParams = this.getSourceBufferParams_(contentType);
  1979.         const stream = streamsByType.get(contentType);
  1980.         // eslint-disable-next-line no-await-in-loop
  1981.         await this.initSourceBuffer_(contentType, stream, stream.codecs);
  1982.         if (this.needSplitMuxedContent_) {
  1983.           this.queues_[ContentType.AUDIO] = [];
  1984.           this.queues_[ContentType.VIDEO] = [];
  1985.         } else {
  1986.           this.queues_[contentType] = [];
  1987.         }
  1989.         this.restoreSourceBufferParams_(contentType, previousParams);
  1990.       }
  1992.       // Fake a seek to catchup the playhead.
  1993.       this.video_.currentTime = currentTime;
  1995.       await sourceBufferAdded;
  1996.     } finally {
  1997.       this.reloadingMediaSource_ = false;
  1999.       this.destroyer_.ensureNotDestroyed();
  2001.       this.eventManager_.listenOnce(this.video_, 'canplaythrough', () => {
  2002.         // Don't use ensureNotDestroyed() from this event listener, because
  2003.         // that results in an uncaught exception.  Instead, just check the
  2004.         // flag.
  2005.         if (this.destroyer_.destroyed()) {
  2006.           return;
  2007.         }
  2009.         this.video_.autoplay = previousAutoPlayState;
  2010.         if (!previousPausedState) {
  2011.           this.video_.play();
  2012.         }
  2013.       });
  2014.     }
  2015.   }
  2017.   /**
  2018.    * Resets the Media Source
  2019.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  2020.    *               shaka.extern.Stream>} streamsByType
  2021.    * @return {!Promise}
  2022.    */
  2023.   reset(streamsByType) {
  2024.     return this.enqueueBlockingOperation_(
  2025.         () => this.reset_(streamsByType));
  2026.   }
  2028.   /**
  2029.    * Codec switch if necessary, this will not resolve until the codec
  2030.    * switch is over.
  2031.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2032.    * @param {string} mimeType
  2033.    * @param {string} codecs
  2034.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  2035.    *               shaka.extern.Stream>} streamsByType
  2036.    * @return {!Promise.<boolean>} true if there was a codec switch,
  2037.    *                              false otherwise.
  2038.    * @private
  2039.    */
  2040.   async codecSwitchIfNecessary_(contentType, mimeType, codecs, streamsByType) {
  2041.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2042.     if (contentType == ContentType.TEXT) {
  2043.       return false;
  2044.     }
  2045.     const MimeUtils = shaka.util.MimeUtils;
  2046.     const currentCodec = MimeUtils.getNormalizedCodec(
  2047.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  2048.     const currentBasicType = MimeUtils.getBasicType(
  2049.         this.sourceBufferTypes_[contentType]);
  2051.     /** @type {?shaka.extern.Transmuxer} */
  2052.     let transmuxer;
  2053.     let transmuxerMuxed = false;
  2054.     let newMimeType = shaka.util.MimeUtils.getFullType(mimeType, codecs);
  2055.     let needTransmux = this.config_.forceTransmux;
  2056.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2057.         (!this.sequenceMode_ &&
  2058.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2059.       needTransmux = true;
  2060.     }
  2061.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2062.     if (needTransmux) {
  2063.       const newMimeTypeWithAllCodecs =
  2064.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codecs);
  2065.       const transmuxerPlugin =
  2066.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2067.       if (transmuxerPlugin) {
  2068.         transmuxer = transmuxerPlugin();
  2069.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2070.             ContentType.AUDIO, (codecs || '').split(','));
  2071.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2072.             ContentType.VIDEO, (codecs || '').split(','));
  2073.         if (audioCodec && videoCodec) {
  2074.           transmuxerMuxed = true;
  2075.           let codec = videoCodec;
  2076.           if (contentType == ContentType.AUDIO) {
  2077.             codec = audioCodec;
  2078.           }
  2079.           newMimeType = transmuxer.convertCodecs(contentType,
  2080.               shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codec));
  2081.         } else {
  2082.           newMimeType =
  2083.               transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2084.         }
  2085.       }
  2086.     }
  2088.     const newCodec = MimeUtils.getNormalizedCodec(
  2089.         MimeUtils.getCodecs(newMimeType));
  2090.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2092.     // Current/new codecs base and basic type match then no need to switch
  2093.     if (currentCodec === newCodec && currentBasicType === newBasicType) {
  2094.       if (this.transmuxers_[contentType] && !transmuxer) {
  2095.         this.transmuxers_[contentType].destroy();
  2096.         delete this.transmuxers_[contentType];
  2097.       } else if (!this.transmuxers_[contentType] && transmuxer) {
  2098.         this.transmuxers_[contentType] = transmuxer;
  2099.       } else if (transmuxer) {
  2100.         // Compare if the transmuxer is different
  2101.         if (this.transmuxers_[contentType] &&
  2102.             this.transmuxers_[contentType].transmux != transmuxer.transmux) {
  2103.           this.transmuxers_[contentType].destroy();
  2104.           delete this.transmuxers_[contentType];
  2105.           this.transmuxers_[contentType] = transmuxer;
  2106.         } else {
  2107.           transmuxer.destroy();
  2108.         }
  2109.       }
  2110.       return false;
  2111.     }
  2113.     let allowChangeType = true;
  2114.     if (this.needSplitMuxedContent_ || (transmuxerMuxed &&
  2115.         transmuxer && !this.transmuxers_[contentType])) {
  2116.       allowChangeType = false;
  2117.     }
  2119.     if (allowChangeType && this.config_.codecSwitchingStrategy ===
  2120.         shaka.config.CodecSwitchingStrategy.SMOOTH &&
  2121.           shaka.media.Capabilities.isChangeTypeSupported()) {
  2122.       await this.changeType(contentType, newMimeType, transmuxer);
  2123.     } else {
  2124.       if (transmuxer) {
  2125.         transmuxer.destroy();
  2126.       }
  2127.       await this.reset(streamsByType);
  2128.     }
  2129.     return true;
  2130.   }
  2132.   /**
  2133.    * Returns true if it's necessary codec switch to load the new stream.
  2134.    *
  2135.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2136.    * @param {shaka.extern.Stream} stream
  2137.    * @param {string} refMimeType
  2138.    * @param {string} refCodecs
  2139.    * @return {boolean}
  2140.    * @private
  2141.    */
  2142.   isCodecSwitchNecessary_(contentType, stream, refMimeType, refCodecs) {
  2143.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2144.       return false;
  2145.     }
  2146.     const MimeUtils = shaka.util.MimeUtils;
  2147.     const currentCodec = MimeUtils.getNormalizedCodec(
  2148.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  2149.     const currentBasicType = MimeUtils.getBasicType(
  2150.         this.sourceBufferTypes_[contentType]);
  2152.     let newMimeType = shaka.util.MimeUtils.getFullType(refMimeType, refCodecs);
  2153.     let needTransmux = this.config_.forceTransmux;
  2154.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2155.         (!this.sequenceMode_ &&
  2156.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2157.       needTransmux = true;
  2158.     }
  2159.     const newMimeTypeWithAllCodecs =
  2160.         shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  2161.             refMimeType, refCodecs);
  2162.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2163.     if (needTransmux) {
  2164.       const transmuxerPlugin =
  2165.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2166.       if (transmuxerPlugin) {
  2167.         const transmuxer = transmuxerPlugin();
  2168.         newMimeType =
  2169.             transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2170.         transmuxer.destroy();
  2171.       }
  2172.     }
  2174.     const newCodec = MimeUtils.getNormalizedCodec(
  2175.         MimeUtils.getCodecs(newMimeType));
  2176.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2178.     return currentCodec !== newCodec || currentBasicType !== newBasicType;
  2179.   }
  2181.   /**
  2182.    * Returns true if it's necessary reset the media source to load the
  2183.    * new stream.
  2184.    *
  2185.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2186.    * @param {shaka.extern.Stream} stream
  2187.    * @param {string} mimeType
  2188.    * @param {string} codecs
  2189.    * @return {boolean}
  2190.    */
  2191.   isResetMediaSourceNecessary(contentType, stream, mimeType, codecs) {
  2192.     if (!this.isCodecSwitchNecessary_(contentType, stream, mimeType, codecs)) {
  2193.       return false;
  2194.     }
  2196.     return this.config_.codecSwitchingStrategy !==
  2197.         shaka.config.CodecSwitchingStrategy.SMOOTH ||
  2198.         !shaka.media.Capabilities.isChangeTypeSupported() ||
  2199.         this.needSplitMuxedContent_;
  2200.   }
  2202.   /**
  2203.    * Update LCEVC Decoder object when ready for LCEVC Decode.
  2204.    * @param {?shaka.lcevc.Dec} lcevcDec
  2205.    */
  2206.   updateLcevcDec(lcevcDec) {
  2207.     this.lcevcDec_ = lcevcDec;
  2208.   }
  2210.   /**
  2211.    * @param {string} mimeType
  2212.    * @return {string}
  2213.    * @private
  2214.    */
  2215.   addExtraFeaturesToMimeType_(mimeType) {
  2216.     const extraFeatures = this.config_.addExtraFeaturesToSourceBuffer(mimeType);
  2217.     const extendedType = mimeType + extraFeatures;
  2218.     shaka.log.debug('Using full mime type', extendedType);
  2220.     return extendedType;
  2221.   }
  2222. };
  2225. /**
  2226.  * Internal reference to window.URL.createObjectURL function to avoid
  2227.  * compatibility issues with other libraries and frameworks such as React
  2228.  * Native. For use in unit tests only, not meant for external use.
  2229.  *
  2230.  * @type {function(?):string}
  2231.  */
  2232. shaka.media.MediaSourceEngine.createObjectURL = window.URL.createObjectURL;
  2235. /**
  2236.  * @typedef {{
  2237.  *   start: function(),
  2238.  *   p: !shaka.util.PublicPromise,
  2239.  *   uri: ?string
  2240.  * }}
  2241.  *
  2242.  * @summary An operation in queue.
  2243.  * @property {function()} start
  2244.  *   The function which starts the operation.
  2245.  * @property {!shaka.util.PublicPromise} p
  2246.  *   The PublicPromise which is associated with this operation.
  2247.  * @property {?string} uri
  2248.  *   A segment URI (if any) associated with this operation.
  2249.  */
  2250. shaka.media.MediaSourceEngine.Operation;
  2253. /**
  2254.  * @enum {string}
  2255.  * @private
  2256.  */
  2257. shaka.media.MediaSourceEngine.SourceBufferMode_ = {
  2258.   SEQUENCE: 'sequence',
  2259.   SEGMENTS: 'segments',
  2260. };
  2263. /**
  2264.  * @typedef {{
  2265.  *   getKeySystem: function():?string,
  2266.  *   onMetadata: function(!Array<shaka.extern.ID3Metadata>, number, ?number)
  2267.  * }}
  2268.  *
  2269.  * @summary Player interface
  2270.  * @property {function():?string} getKeySystem
  2271.  *   Gets currently used key system or null if not used.
  2272.  * @property {function(
  2273.  *     !Array<shaka.extern.ID3Metadata>, number, ?number)} onMetadata
  2274.  *   Callback to use when metadata arrives.
  2275.  */
  2276. shaka.media.MediaSourceEngine.PlayerInterface;
  2278. /**
  2279.  * @typedef {{
  2280.  *   timestampOffset: number,
  2281.  *   appendWindowStart: number,
  2282.  *   appendWindowEnd: number
  2283.  * }}
  2284.  */
  2285. shaka.media.MediaSourceEngine.SourceBufferParams;