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|ManagedMediaSource)} */
  120.     this.mediaSource_ = this.createMediaSource(this.mediaSourceOpen_);
  122.     /** @private {boolean} */
  123.     this.reloadingMediaSource_ = false;
  125.     /** @type {!shaka.util.Destroyer} */
  126.     this.destroyer_ = new shaka.util.Destroyer(() => this.doDestroy_());
  128.     /** @private {boolean} */
  129.     this.sequenceMode_ = false;
  131.     /** @private {string} */
  132.     this.manifestType_ = shaka.media.ManifestParser.UNKNOWN;
  134.     /** @private {boolean} */
  135.     this.ignoreManifestTimestampsInSegmentsMode_ = false;
  137.     /** @private {boolean} */
  138.     this.attemptTimestampOffsetCalculation_ = false;
  140.     /** @private {!shaka.util.PublicPromise.<number>} */
  141.     this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
  143.     /** @private {boolean} */
  144.     this.needSplitMuxedContent_ = false;
  146.     /** @private {boolean} */
  147.     this.streamingAllowed_ = true;
  149.     /** @private {?number} */
  150.     this.lastDuration_ = null;
  152.     /** @private {?shaka.util.TsParser} */
  153.     this.tsParser_ = null;
  155.     /** @private {?number} */
  156.     this.firstVideoTimestamp_ = null;
  158.     /** @private {?number} */
  159.     this.firstAudioTimestamp_ = null;
  161.     /** @private {!shaka.util.PublicPromise.<number>} */
  162.     this.audioCompensation_ = new shaka.util.PublicPromise();
  163.   }
  165.   /**
  166.    * Create a MediaSource object, attach it to the video element, and return it.
  167.    * Resolves the given promise when the MediaSource is ready.
  168.    *
  169.    * Replaced by unit tests.
  170.    *
  171.    * @param {!shaka.util.PublicPromise} p
  172.    * @return {!(MediaSource|ManagedMediaSource)}
  173.    */
  174.   createMediaSource(p) {
  175.     if (window.ManagedMediaSource) {
  176.       this.video_.disableRemotePlayback = true;
  178.       const mediaSource = new ManagedMediaSource();
  180.       this.eventManager_.listen(
  181.           mediaSource, 'startstreaming', () => {
  182.             this.streamingAllowed_ = true;
  183.           });
  185.       this.eventManager_.listen(
  186.           mediaSource, 'endstreaming', () => {
  187.             this.streamingAllowed_ = false;
  188.           });
  190.       this.eventManager_.listenOnce(
  191.           mediaSource, 'sourceopen', () => this.onSourceOpen_(p));
  193.       // Correctly set when playback has begun.
  194.       this.eventManager_.listenOnce(this.video_, 'playing', () => {
  195.         this.playbackHasBegun_ = true;
  196.       });
  198.       this.url_ = shaka.media.MediaSourceEngine.createObjectURL(mediaSource);
  200.       this.video_.src = this.url_;
  202.       return mediaSource;
  203.     } else {
  204.       const mediaSource = new MediaSource();
  206.       // Set up MediaSource on the video element.
  207.       this.eventManager_.listenOnce(
  208.           mediaSource, 'sourceopen', () => this.onSourceOpen_(p));
  210.       // Correctly set when playback has begun.
  211.       this.eventManager_.listenOnce(this.video_, 'playing', () => {
  212.         this.playbackHasBegun_ = true;
  213.       });
  215.       // Store the object URL for releasing it later.
  216.       this.url_ = shaka.media.MediaSourceEngine.createObjectURL(mediaSource);
  218.       this.video_.src = this.url_;
  220.       return mediaSource;
  221.     }
  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.     }
  404.     if (this.textDisplayer_) {
  405.       cleanup.push(this.textDisplayer_.destroy());
  406.     }
  408.     for (const contentType in this.transmuxers_) {
  409.       cleanup.push(this.transmuxers_[contentType].destroy());
  410.     }
  413.     await Promise.all(cleanup);
  414.     if (this.eventManager_) {
  415.       this.eventManager_.release();
  416.       this.eventManager_ = null;
  417.     }
  419.     if (this.video_) {
  420.       // "unload" the video element.
  421.       this.video_.removeAttribute('src');
  422.       this.video_.load();
  423.       this.video_ = null;
  424.     }
  426.     this.config_ = null;
  427.     this.mediaSource_ = null;
  428.     this.textEngine_ = null;
  429.     this.textDisplayer_ = null;
  430.     this.sourceBuffers_ = {};
  431.     this.transmuxers_ = {};
  432.     this.captionParser_ = null;
  433.     if (goog.DEBUG) {
  434.       for (const contentType in this.queues_) {
  435.         goog.asserts.assert(
  436.             this.queues_[contentType].length == 0,
  437.             contentType + ' queue should be empty after destroy!');
  438.       }
  439.     }
  440.     this.queues_ = {};
  442.     // This object is owned by Player
  443.     this.lcevcDec_ = null;
  445.     this.tsParser_ = null;
  446.     this.playerInterface_ = null;
  447.   }
  449.   /**
  450.    * @return {!Promise} Resolved when MediaSource is open and attached to the
  451.    *   media element.  This process is actually initiated by the constructor.
  452.    */
  453.   open() {
  454.     return this.mediaSourceOpen_;
  455.   }
  457.   /**
  458.    * Initialize MediaSourceEngine.
  459.    *
  460.    * Note that it is not valid to call this multiple times, except to add or
  461.    * reinitialize text streams.
  462.    *
  463.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  464.    *               shaka.extern.Stream>} streamsByType
  465.    *   A map of content types to streams.  All streams must be supported
  466.    *   according to MediaSourceEngine.isStreamSupported.
  467.    * @param {boolean=} sequenceMode
  468.    *   If true, the media segments are appended to the SourceBuffer in strict
  469.    *   sequence.
  470.    * @param {string=} manifestType
  471.    *   Indicates the type of the manifest.
  472.    * @param {boolean=} ignoreManifestTimestampsInSegmentsMode
  473.    *   If true, don't adjust the timestamp offset to account for manifest
  474.    *   segment durations being out of sync with segment durations. In other
  475.    *   words, assume that there are no gaps in the segments when appending
  476.    *   to the SourceBuffer, even if the manifest and segment times disagree.
  477.    *   Indicates if the manifest has text streams.
  478.    *
  479.    * @return {!Promise}
  480.    */
  481.   async init(streamsByType, sequenceMode=false,
  482.       manifestType=shaka.media.ManifestParser.UNKNOWN,
  483.       ignoreManifestTimestampsInSegmentsMode=false) {
  484.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  486.     await this.mediaSourceOpen_;
  488.     this.sequenceMode_ = sequenceMode;
  489.     this.manifestType_ = manifestType;
  490.     this.ignoreManifestTimestampsInSegmentsMode_ =
  491.       ignoreManifestTimestampsInSegmentsMode;
  493.     this.attemptTimestampOffsetCalculation_ = !this.sequenceMode_ &&
  494.         this.manifestType_ == shaka.media.ManifestParser.HLS &&
  495.         !this.ignoreManifestTimestampsInSegmentsMode_;
  497.     this.tsParser_ = null;
  499.     for (const contentType of streamsByType.keys()) {
  500.       const stream = streamsByType.get(contentType);
  501.       // eslint-disable-next-line no-await-in-loop
  502.       await this.initSourceBuffer_(contentType, stream, stream.codecs);
  503.       if (this.needSplitMuxedContent_) {
  504.         this.queues_[ContentType.AUDIO] = [];
  505.         this.queues_[ContentType.VIDEO] = [];
  506.       } else {
  507.         this.queues_[contentType] = [];
  508.       }
  509.     }
  510.   }
  512.   /**
  513.    * Initialize a specific SourceBuffer.
  514.    *
  515.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  516.    * @param {shaka.extern.Stream} stream
  517.    * @param {string} codecs
  518.    * @return {!Promise}
  519.    * @private
  520.    */
  521.   async initSourceBuffer_(contentType, stream, codecs) {
  522.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  524.     goog.asserts.assert(
  525.         await shaka.media.MediaSourceEngine.isStreamSupported(
  526.             stream, contentType),
  527.         'Type negotiation should happen before MediaSourceEngine.init!');
  529.     let mimeType = shaka.util.MimeUtils.getFullType(
  530.         stream.mimeType, codecs);
  531.     if (contentType == ContentType.TEXT) {
  532.       this.reinitText(mimeType, this.sequenceMode_, stream.external);
  533.     } else {
  534.       let needTransmux = this.config_.forceTransmux;
  535.       if (!shaka.media.Capabilities.isTypeSupported(mimeType) ||
  536.           (!this.sequenceMode_ &&
  537.           shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType))) {
  538.         needTransmux = true;
  539.       }
  540.       const mimeTypeWithAllCodecs =
  541.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  542.               stream.mimeType, codecs);
  543.       if (needTransmux) {
  544.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  545.             ContentType.AUDIO, (codecs || '').split(','));
  546.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  547.             ContentType.VIDEO, (codecs || '').split(','));
  548.         if (audioCodec && videoCodec) {
  549.           this.needSplitMuxedContent_ = true;
  550.           await this.initSourceBuffer_(ContentType.AUDIO, stream, audioCodec);
  551.           await this.initSourceBuffer_(ContentType.VIDEO, stream, videoCodec);
  552.           return;
  553.         }
  554.         const transmuxerPlugin = shaka.transmuxer.TransmuxerEngine
  555.             .findTransmuxer(mimeTypeWithAllCodecs);
  556.         if (transmuxerPlugin) {
  557.           const transmuxer = transmuxerPlugin();
  558.           this.transmuxers_[contentType] = transmuxer;
  559.           mimeType =
  560.               transmuxer.convertCodecs(contentType, mimeTypeWithAllCodecs);
  561.         }
  562.       }
  563.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  565.       this.destroyer_.ensureNotDestroyed();
  567.       let sourceBuffer;
  569.       try {
  570.         sourceBuffer = this.mediaSource_.addSourceBuffer(type);
  571.       } catch (exception) {
  572.         throw new shaka.util.Error(
  573.             shaka.util.Error.Severity.CRITICAL,
  574.             shaka.util.Error.Category.MEDIA,
  575.             shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  576.             exception,
  577.             'The mediaSource_ status was ' + this.mediaSource_.readyState +
  578.             ' expected \'open\'',
  579.             null);
  580.       }
  582.       if (this.sequenceMode_) {
  583.         sourceBuffer.mode =
  584.             shaka.media.MediaSourceEngine.SourceBufferMode_.SEQUENCE;
  585.       }
  587.       this.eventManager_.listen(
  588.           sourceBuffer, 'error',
  589.           () => this.onError_(contentType));
  590.       this.eventManager_.listen(
  591.           sourceBuffer, 'updateend',
  592.           () => this.onUpdateEnd_(contentType));
  593.       this.sourceBuffers_[contentType] = sourceBuffer;
  594.       this.sourceBufferTypes_[contentType] = mimeType;
  595.       this.expectedEncryption_[contentType] = !!stream.drmInfos.length;
  596.     }
  597.   }
  599.   /**
  600.    * Called by the Player to provide an updated configuration any time it
  601.    * changes. Must be called at least once before init().
  602.    *
  603.    * @param {shaka.extern.MediaSourceConfiguration} config
  604.    */
  605.   configure(config) {
  606.     this.config_ = config;
  607.     if (this.textEngine_) {
  608.       this.textEngine_.setModifyCueCallback(config.modifyCueCallback);
  609.     }
  610.   }
  612.   /**
  613.    * Indicate if the streaming is allowed by MediaSourceEngine.
  614.    * If we using MediaSource we allways returns true.
  615.    *
  616.    * @return {boolean}
  617.    */
  618.   isStreamingAllowed() {
  619.     return this.streamingAllowed_;
  620.   }
  622.   /**
  623.    * Reinitialize the TextEngine for a new text type.
  624.    * @param {string} mimeType
  625.    * @param {boolean} sequenceMode
  626.    * @param {boolean} external
  627.    */
  628.   reinitText(mimeType, sequenceMode, external) {
  629.     if (!this.textEngine_) {
  630.       this.textEngine_ = new shaka.text.TextEngine(this.textDisplayer_);
  631.       if (this.textEngine_) {
  632.         this.textEngine_.setModifyCueCallback(this.config_.modifyCueCallback);
  633.       }
  634.     }
  635.     this.textEngine_.initParser(mimeType, sequenceMode,
  636.         external || this.segmentRelativeVttTiming_, this.manifestType_);
  637.   }
  639.   /**
  640.    * @return {boolean} True if the MediaSource is in an "ended" state, or if the
  641.    *   object has been destroyed.
  642.    */
  643.   ended() {
  644.     if (this.reloadingMediaSource_) {
  645.       return false;
  646.     }
  647.     return this.mediaSource_ ? this.mediaSource_.readyState == 'ended' : true;
  648.   }
  650.   /**
  651.    * Gets the first timestamp in buffer for the given content type.
  652.    *
  653.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  654.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  655.    */
  656.   bufferStart(contentType) {
  657.     if (this.reloadingMediaSource_ ||
  658.           !Object.keys(this.sourceBuffers_).length) {
  659.       return null;
  660.     }
  661.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  662.     if (contentType == ContentType.TEXT) {
  663.       return this.textEngine_.bufferStart();
  664.     }
  665.     return shaka.media.TimeRangesUtils.bufferStart(
  666.         this.getBuffered_(contentType));
  667.   }
  669.   /**
  670.    * Gets the last timestamp in buffer for the given content type.
  671.    *
  672.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  673.    * @return {?number} The timestamp in seconds, or null if nothing is buffered.
  674.    */
  675.   bufferEnd(contentType) {
  676.     if (this.reloadingMediaSource_) {
  677.       return null;
  678.     }
  679.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  680.     if (contentType == ContentType.TEXT) {
  681.       return this.textEngine_.bufferEnd();
  682.     }
  683.     return shaka.media.TimeRangesUtils.bufferEnd(
  684.         this.getBuffered_(contentType));
  685.   }
  687.   /**
  688.    * Determines if the given time is inside the buffered range of the given
  689.    * content type.
  690.    *
  691.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  692.    * @param {number} time Playhead time
  693.    * @return {boolean}
  694.    */
  695.   isBuffered(contentType, time) {
  696.     if (this.reloadingMediaSource_) {
  697.       return false;
  698.     }
  699.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  700.     if (contentType == ContentType.TEXT) {
  701.       return this.textEngine_.isBuffered(time);
  702.     } else {
  703.       const buffered = this.getBuffered_(contentType);
  704.       return shaka.media.TimeRangesUtils.isBuffered(buffered, time);
  705.     }
  706.   }
  708.   /**
  709.    * Computes how far ahead of the given timestamp is buffered for the given
  710.    * content type.
  711.    *
  712.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  713.    * @param {number} time
  714.    * @return {number} The amount of time buffered ahead in seconds.
  715.    */
  716.   bufferedAheadOf(contentType, time) {
  717.     if (this.reloadingMediaSource_) {
  718.       return 0;
  719.     }
  720.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  721.     if (contentType == ContentType.TEXT) {
  722.       return this.textEngine_.bufferedAheadOf(time);
  723.     } else {
  724.       const buffered = this.getBuffered_(contentType);
  725.       return shaka.media.TimeRangesUtils.bufferedAheadOf(buffered, time);
  726.     }
  727.   }
  729.   /**
  730.    * Returns info about what is currently buffered.
  731.    * @return {shaka.extern.BufferedInfo}
  732.    */
  733.   getBufferedInfo() {
  734.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  735.     const TimeRangesUtils = shaka.media.TimeRangesUtils;
  737.     const info = {
  738.       total: this.reloadingMediaSource_ ? [] :
  739.         TimeRangesUtils.getBufferedInfo(this.video_.buffered),
  740.       audio: this.reloadingMediaSource_ ? [] :
  741.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.AUDIO)),
  742.       video: this.reloadingMediaSource_ ? [] :
  743.         TimeRangesUtils.getBufferedInfo(this.getBuffered_(ContentType.VIDEO)),
  744.       text: [],
  745.     };
  747.     if (this.textEngine_) {
  748.       const start = this.textEngine_.bufferStart();
  749.       const end = this.textEngine_.bufferEnd();
  751.       if (start != null && end != null) {
  752.         info.text.push({start: start, end: end});
  753.       }
  754.     }
  755.     return info;
  756.   }
  758.   /**
  759.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  760.    * @return {TimeRanges} The buffered ranges for the given content type, or
  761.    *   null if the buffered ranges could not be obtained.
  762.    * @private
  763.    */
  764.   getBuffered_(contentType) {
  765.     try {
  766.       return this.sourceBuffers_[contentType].buffered;
  767.     } catch (exception) {
  768.       if (contentType in this.sourceBuffers_) {
  769.         // Note: previous MediaSource errors may cause access to |buffered| to
  770.         // throw.
  771.         shaka.log.error('failed to get buffered range for ' + contentType,
  772.             exception);
  773.       }
  774.       return null;
  775.     }
  776.   }
  778.   /**
  779.    * Create a new closed caption parser. This will ONLY be replaced by tests as
  780.    * a way to inject fake closed caption parser instances.
  781.    *
  782.    * @param {string} mimeType
  783.    * @return {!shaka.media.IClosedCaptionParser}
  784.    */
  785.   getCaptionParser(mimeType) {
  786.     return new shaka.media.ClosedCaptionParser(mimeType);
  787.   }
  789.   /**
  790.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  791.    * @param {!BufferSource} data
  792.    * @param {?shaka.media.SegmentReference} reference The segment reference
  793.    *   we are appending, or null for init segments
  794.    * @param {!string} mimeType
  795.    * @param {!number} timestampOffset
  796.    * @return {?number}
  797.    * @private
  798.    */
  799.   getTimestampAndDispatchMetadata_(contentType, data, reference, mimeType,
  800.       timestampOffset) {
  801.     let timestamp = null;
  803.     const uint8ArrayData = shaka.util.BufferUtils.toUint8(data);
  804.     if (shaka.util.MimeUtils.RAW_FORMATS.includes(mimeType)) {
  805.       const frames = shaka.util.Id3Utils.getID3Frames(uint8ArrayData);
  806.       if (frames.length && reference) {
  807.         const metadataTimestamp = frames.find((frame) => {
  808.           return frame.description ===
  809.               'com.apple.streaming.transportStreamTimestamp';
  810.         });
  811.         if (metadataTimestamp && metadataTimestamp.data) {
  812.           timestamp = Math.round(metadataTimestamp.data) / 1000;
  813.         }
  814.         /** @private {shaka.extern.ID3Metadata} */
  815.         const metadata = {
  816.           cueTime: reference.startTime,
  817.           data: uint8ArrayData,
  818.           frames: frames,
  819.           dts: reference.startTime,
  820.           pts: reference.startTime,
  821.         };
  822.         this.playerInterface_.onMetadata(
  823.             [metadata], /* offset= */ 0, reference.endTime);
  824.       }
  825.     } else if (mimeType.includes('/mp4') &&
  826.         reference && reference.timestampOffset == 0 &&
  827.         reference.initSegmentReference &&
  828.         reference.initSegmentReference.timescale) {
  829.       const timescale = reference.initSegmentReference.timescale;
  830.       if (!isNaN(timescale)) {
  831.         const Mp4Parser = shaka.util.Mp4Parser;
  832.         let startTime = 0;
  833.         let parsedMedia = false;
  834.         new Mp4Parser()
  835.             .box('moof', Mp4Parser.children)
  836.             .box('traf', Mp4Parser.children)
  837.             .fullBox('tfdt', (box) => {
  838.               goog.asserts.assert(
  839.                   box.version == 0 || box.version == 1,
  840.                   'TFDT version can only be 0 or 1');
  841.               const parsed = shaka.util.Mp4BoxParsers.parseTFDTInaccurate(
  842.                   box.reader, box.version);
  843.               startTime = parsed.baseMediaDecodeTime / timescale;
  844.               parsedMedia = true;
  845.               box.parser.stop();
  846.             }).parse(data, /* partialOkay= */ true);
  847.         if (parsedMedia) {
  848.           timestamp = startTime;
  849.         }
  850.       }
  851.     } else if (!mimeType.includes('/mp4') && !mimeType.includes('/webm') &&
  852.         shaka.util.TsParser.probe(uint8ArrayData)) {
  853.       if (!this.tsParser_) {
  854.         this.tsParser_ = new shaka.util.TsParser();
  855.       } else {
  856.         this.tsParser_.clearData();
  857.       }
  858.       const tsParser = this.tsParser_.parse(uint8ArrayData);
  859.       const startTime = tsParser.getStartTime(contentType);
  860.       if (startTime != null) {
  861.         timestamp = startTime;
  862.       }
  863.       const metadata = tsParser.getMetadata();
  864.       if (metadata.length) {
  865.         this.playerInterface_.onMetadata(metadata, timestampOffset,
  866.             reference ? reference.endTime : null);
  867.       }
  868.     }
  869.     return timestamp;
  870.   }
  872.   /**
  873.    * Enqueue an operation to append data to the SourceBuffer.
  874.    * Start and end times are needed for TextEngine, but not for MediaSource.
  875.    * Start and end times may be null for initialization segments; if present
  876.    * they are relative to the presentation timeline.
  877.    *
  878.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  879.    * @param {!BufferSource} data
  880.    * @param {?shaka.media.SegmentReference} reference The segment reference
  881.    *   we are appending, or null for init segments
  882.    * @param {shaka.extern.Stream} stream
  883.    * @param {?boolean} hasClosedCaptions True if the buffer contains CEA closed
  884.    *   captions
  885.    * @param {boolean=} seeked True if we just seeked
  886.    * @param {boolean=} adaptation True if we just automatically switched active
  887.    *   variant(s).
  888.    * @param {boolean=} isChunkedData True if we add to the buffer from the
  889.    *   partial read of the segment.
  890.    * @return {!Promise}
  891.    */
  892.   async appendBuffer(
  893.       contentType, data, reference, stream, hasClosedCaptions, seeked = false,
  894.       adaptation = false, isChunkedData = false, fromSplit = false) {
  895.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  897.     if (contentType == ContentType.TEXT) {
  898.       if (this.sequenceMode_) {
  899.         // This won't be known until the first video segment is appended.
  900.         const offset = await this.textSequenceModeOffset_;
  901.         this.textEngine_.setTimestampOffset(offset);
  902.       }
  903.       await this.textEngine_.appendBuffer(
  904.           data,
  905.           reference ? reference.startTime : null,
  906.           reference ? reference.endTime : null,
  907.           reference ? reference.getUris()[0] : null);
  908.       return;
  909.     }
  911.     if (!fromSplit && this.needSplitMuxedContent_) {
  912.       await this.appendBuffer(ContentType.AUDIO, data, reference, stream,
  913.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  914.           /* fromSplit= */ true);
  915.       await this.appendBuffer(ContentType.VIDEO, data, reference, stream,
  916.           hasClosedCaptions, seeked, adaptation, isChunkedData,
  917.           /* fromSplit= */ true);
  918.       return;
  919.     }
  921.     if (!this.sourceBuffers_[contentType]) {
  922.       shaka.log.warning('Attempted to restore a non-existent source buffer');
  923.       return;
  924.     }
  926.     let timestampOffset = this.sourceBuffers_[contentType].timestampOffset;
  928.     let mimeType = this.sourceBufferTypes_[contentType];
  929.     if (this.transmuxers_[contentType]) {
  930.       mimeType = this.transmuxers_[contentType].getOriginalMimeType();
  931.     }
  932.     if (reference) {
  933.       const timestamp = this.getTimestampAndDispatchMetadata_(
  934.           contentType, data, reference, mimeType, timestampOffset);
  935.       if (timestamp != null) {
  936.         if (this.firstVideoTimestamp_ == null &&
  937.             contentType == ContentType.VIDEO) {
  938.           this.firstVideoTimestamp_ = timestamp;
  939.           if (this.firstAudioTimestamp_ != null) {
  940.             const compensation =
  941.                 this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  942.             this.audioCompensation_.resolve(compensation);
  943.           }
  944.         }
  945.         if (this.firstAudioTimestamp_ == null &&
  946.             contentType == ContentType.AUDIO) {
  947.           this.firstAudioTimestamp_ = timestamp;
  948.           if (this.firstVideoTimestamp_ != null) {
  949.             const compensation =
  950.                 this.firstVideoTimestamp_ - this.firstAudioTimestamp_;
  951.             this.audioCompensation_.resolve(compensation);
  952.           }
  953.         }
  954.         const calculatedTimestampOffset = reference.startTime - timestamp;
  955.         const timestampOffsetDifference =
  956.             Math.abs(timestampOffset - calculatedTimestampOffset);
  957.         if ((timestampOffsetDifference >= 0.001 || seeked || adaptation) &&
  958.             (!isChunkedData || calculatedTimestampOffset > 0 ||
  959.             !timestampOffset)) {
  960.           timestampOffset = calculatedTimestampOffset;
  961.           if (this.attemptTimestampOffsetCalculation_) {
  962.             this.enqueueOperation_(
  963.                 contentType,
  964.                 () => this.abort_(contentType),
  965.                 null);
  966.             this.enqueueOperation_(
  967.                 contentType,
  968.                 () => this.setTimestampOffset_(contentType, timestampOffset),
  969.                 null);
  970.           }
  971.         }
  972.         // Timestamps can only be reliably extracted from video, not audio.
  973.         // Packed audio formats do not have internal timestamps at all.
  974.         // Prefer video for this when available.
  975.         const isBestSourceBufferForTimestamps =
  976.             contentType == ContentType.VIDEO ||
  977.             !(ContentType.VIDEO in this.sourceBuffers_);
  978.         if (this.sequenceMode_ && isBestSourceBufferForTimestamps) {
  979.           this.textSequenceModeOffset_.resolve(timestampOffset);
  980.         }
  981.       }
  982.     }
  983.     if (hasClosedCaptions && contentType == ContentType.VIDEO) {
  984.       if (!this.textEngine_) {
  985.         this.reinitText(shaka.util.MimeUtils.CEA608_CLOSED_CAPTION_MIMETYPE,
  986.             this.sequenceMode_, /* external= */ false);
  987.       }
  988.       if (!this.captionParser_) {
  989.         const basicType = mimeType.split(';', 1)[0];
  990.         this.captionParser_ = this.getCaptionParser(basicType);
  991.       }
  992.       // If it is the init segment for closed captions, initialize the closed
  993.       // caption parser.
  994.       if (!reference) {
  995.         this.captionParser_.init(data, adaptation);
  996.       } else {
  997.         const closedCaptions = this.captionParser_.parseFrom(data);
  998.         if (closedCaptions.length) {
  999.           this.textEngine_.storeAndAppendClosedCaptions(
  1000.               closedCaptions,
  1001.               reference.startTime,
  1002.               reference.endTime,
  1003.               timestampOffset);
  1004.         }
  1005.       }
  1006.     }
  1008.     if (this.transmuxers_[contentType]) {
  1009.       data = await this.transmuxers_[contentType].transmux(
  1010.           data, stream, reference, this.mediaSource_.duration, contentType);
  1011.     }
  1013.     data = this.workAroundBrokenPlatforms_(
  1014.         data, reference ? reference.startTime : null, contentType,
  1015.         reference ? reference.getUris()[0] : null);
  1017.     if (reference && this.sequenceMode_ && contentType != ContentType.TEXT) {
  1018.       // In sequence mode, for non-text streams, if we just cleared the buffer
  1019.       // and are either performing an unbuffered seek or handling an automatic
  1020.       // adaptation, we need to set a new timestampOffset on the sourceBuffer.
  1021.       if (seeked || adaptation) {
  1022.         let timestampOffset = reference.startTime;
  1023.         // Audio and video may not be aligned, so we will compensate for audio
  1024.         // if necessary.
  1025.         if (this.manifestType_ == shaka.media.ManifestParser.HLS &&
  1026.             !this.needSplitMuxedContent_ &&
  1027.             contentType == ContentType.AUDIO &&
  1028.             this.sourceBuffers_[ContentType.VIDEO]) {
  1029.           const compensation = await this.audioCompensation_;
  1030.           // Only apply compensation if the difference is greater than 100ms
  1031.           if (Math.abs(compensation) > 0.1) {
  1032.             timestampOffset -= compensation;
  1033.           }
  1034.         }
  1035.         // The logic to call abort() before setting the timestampOffset is
  1036.         // extended during unbuffered seeks or automatic adaptations; it is
  1037.         // possible for the append state to be PARSING_MEDIA_SEGMENT from the
  1038.         // previous SourceBuffer#appendBuffer() call.
  1039.         this.enqueueOperation_(
  1040.             contentType,
  1041.             () => this.abort_(contentType),
  1042.             null);
  1043.         this.enqueueOperation_(
  1044.             contentType,
  1045.             () => this.setTimestampOffset_(contentType, timestampOffset),
  1046.             null);
  1047.       }
  1048.     }
  1050.     let bufferedBefore = null;
  1052.     await this.enqueueOperation_(contentType, () => {
  1053.       if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1054.         bufferedBefore = this.getBuffered_(contentType);
  1055.       }
  1056.       this.append_(contentType, data, timestampOffset);
  1057.     }, reference ? reference.getUris()[0] : null);
  1059.     if (goog.DEBUG && reference && !reference.isPreload() && !isChunkedData) {
  1060.       const bufferedAfter = this.getBuffered_(contentType);
  1061.       const newBuffered = shaka.media.TimeRangesUtils.computeAddedRange(
  1062.           bufferedBefore, bufferedAfter);
  1063.       if (newBuffered) {
  1064.         const segmentDuration = reference.endTime - reference.startTime;
  1065.         // Check end times instead of start times.  We may be overwriting a
  1066.         // buffer and only the end changes, and that would be fine.
  1067.         // Also, exclude tiny segments.  Sometimes alignment segments as small
  1068.         // as 33ms are seen in Google DAI content.  For such tiny segments,
  1069.         // half a segment duration would be no issue.
  1070.         const offset = Math.abs(newBuffered.end - reference.endTime);
  1071.         if (segmentDuration > 0.100 && offset > segmentDuration / 2) {
  1072.           shaka.log.error('Possible encoding problem detected!',
  1073.               'Unexpected buffered range for reference', reference,
  1074.               'from URIs', reference.getUris(),
  1075.               'should be', {start: reference.startTime, end: reference.endTime},
  1076.               'but got', newBuffered);
  1077.         }
  1078.       }
  1079.     }
  1080.   }
  1082.   /**
  1083.    * Set the selected closed captions Id and language.
  1084.    *
  1085.    * @param {string} id
  1086.    */
  1087.   setSelectedClosedCaptionId(id) {
  1088.     const VIDEO = shaka.util.ManifestParserUtils.ContentType.VIDEO;
  1089.     const videoBufferEndTime = this.bufferEnd(VIDEO) || 0;
  1090.     this.textEngine_.setSelectedClosedCaptionId(id, videoBufferEndTime);
  1091.   }
  1093.   /** Disable embedded closed captions. */
  1094.   clearSelectedClosedCaptionId() {
  1095.     if (this.textEngine_) {
  1096.       this.textEngine_.setSelectedClosedCaptionId('', 0);
  1097.     }
  1098.   }
  1100.   /**
  1101.    * Enqueue an operation to remove data from the SourceBuffer.
  1102.    *
  1103.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1104.    * @param {number} startTime relative to the start of the presentation
  1105.    * @param {number} endTime relative to the start of the presentation
  1106.    * @return {!Promise}
  1107.    */
  1108.   async remove(contentType, startTime, endTime) {
  1109.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1110.     if (contentType == ContentType.TEXT) {
  1111.       await this.textEngine_.remove(startTime, endTime);
  1112.     } else {
  1113.       await this.enqueueOperation_(
  1114.           contentType,
  1115.           () => this.remove_(contentType, startTime, endTime),
  1116.           null);
  1117.       if (this.needSplitMuxedContent_) {
  1118.         await this.enqueueOperation_(
  1119.             ContentType.AUDIO,
  1120.             () => this.remove_(ContentType.AUDIO, startTime, endTime),
  1121.             null);
  1122.       }
  1123.     }
  1124.   }
  1126.   /**
  1127.    * Enqueue an operation to clear the SourceBuffer.
  1128.    *
  1129.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1130.    * @return {!Promise}
  1131.    */
  1132.   async clear(contentType) {
  1133.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1134.     if (contentType == ContentType.TEXT) {
  1135.       if (!this.textEngine_) {
  1136.         return;
  1137.       }
  1138.       await this.textEngine_.remove(0, Infinity);
  1139.     } else {
  1140.       // Note that not all platforms allow clearing to Infinity.
  1141.       await this.enqueueOperation_(
  1142.           contentType,
  1143.           () => this.remove_(contentType, 0, this.mediaSource_.duration),
  1144.           null);
  1145.       if (this.needSplitMuxedContent_) {
  1146.         await this.enqueueOperation_(
  1147.             ContentType.AUDIO,
  1148.             () => this.remove_(
  1149.                 ContentType.AUDIO, 0, this.mediaSource_.duration),
  1150.             null);
  1151.       }
  1152.     }
  1153.   }
  1155.   /**
  1156.    * Fully reset the state of the caption parser owned by MediaSourceEngine.
  1157.    */
  1158.   resetCaptionParser() {
  1159.     if (this.captionParser_) {
  1160.       this.captionParser_.reset();
  1161.     }
  1162.   }
  1164.   /**
  1165.    * Enqueue an operation to flush the SourceBuffer.
  1166.    * This is a workaround for what we believe is a Chromecast bug.
  1167.    *
  1168.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1169.    * @return {!Promise}
  1170.    */
  1171.   async flush(contentType) {
  1172.     // Flush the pipeline.  Necessary on Chromecast, even though we have removed
  1173.     // everything.
  1174.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1175.     if (contentType == ContentType.TEXT) {
  1176.       // Nothing to flush for text.
  1177.       return;
  1178.     }
  1179.     await this.enqueueOperation_(
  1180.         contentType,
  1181.         () => this.flush_(contentType),
  1182.         null);
  1183.     if (this.needSplitMuxedContent_) {
  1184.       await this.enqueueOperation_(
  1185.           ContentType.AUDIO,
  1186.           () => this.flush_(ContentType.AUDIO),
  1187.           null);
  1188.     }
  1189.   }
  1191.   /**
  1192.    * Sets the timestamp offset and append window end for the given content type.
  1193.    *
  1194.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1195.    * @param {number} timestampOffset The timestamp offset.  Segments which start
  1196.    *   at time t will be inserted at time t + timestampOffset instead.  This
  1197.    *   value does not affect segments which have already been inserted.
  1198.    * @param {number} appendWindowStart The timestamp to set the append window
  1199.    *   start to.  For future appends, frames/samples with timestamps less than
  1200.    *   this value will be dropped.
  1201.    * @param {number} appendWindowEnd The timestamp to set the append window end
  1202.    *   to.  For future appends, frames/samples with timestamps greater than this
  1203.    *   value will be dropped.
  1204.    * @param {boolean} ignoreTimestampOffset  If true, the timestampOffset will
  1205.    *   not be applied in this step.
  1206.    * @param {string} mimeType
  1207.    * @param {string} codecs
  1208.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1209.    *               shaka.extern.Stream>} streamsByType
  1210.    *   A map of content types to streams.  All streams must be supported
  1211.    *   according to MediaSourceEngine.isStreamSupported.
  1212.    *
  1213.    * @return {!Promise}
  1214.    */
  1215.   async setStreamProperties(
  1216.       contentType, timestampOffset, appendWindowStart, appendWindowEnd,
  1217.       ignoreTimestampOffset, mimeType, codecs, streamsByType) {
  1218.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1219.     if (contentType == ContentType.TEXT) {
  1220.       if (!ignoreTimestampOffset) {
  1221.         this.textEngine_.setTimestampOffset(timestampOffset);
  1222.       }
  1223.       this.textEngine_.setAppendWindow(appendWindowStart, appendWindowEnd);
  1224.       return;
  1225.     }
  1226.     const operations = [];
  1228.     const hasChangedCodecs = await this.codecSwitchIfNecessary_(
  1229.         contentType, mimeType, codecs, streamsByType);
  1231.     if (!hasChangedCodecs) {
  1232.       // Queue an abort() to help MSE splice together overlapping segments.
  1233.       // We set appendWindowEnd when we change periods in DASH content, and the
  1234.       // period transition may result in overlap.
  1235.       //
  1236.       // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1237.       // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1238.       // timestamp offset.  By calling abort(), we reset the state so we can
  1239.       // set it.
  1240.       operations.push(this.enqueueOperation_(
  1241.           contentType,
  1242.           () => this.abort_(contentType),
  1243.           null));
  1244.       if (this.needSplitMuxedContent_) {
  1245.         operations.push(this.enqueueOperation_(
  1246.             ContentType.AUDIO,
  1247.             () => this.abort_(ContentType.AUDIO),
  1248.             null));
  1249.       }
  1250.     }
  1251.     if (!ignoreTimestampOffset) {
  1252.       operations.push(this.enqueueOperation_(
  1253.           contentType,
  1254.           () => this.setTimestampOffset_(contentType, timestampOffset),
  1255.           null));
  1256.       if (this.needSplitMuxedContent_) {
  1257.         operations.push(this.enqueueOperation_(
  1258.             ContentType.AUDIO,
  1259.             () => this.setTimestampOffset_(
  1260.                 ContentType.AUDIO, timestampOffset),
  1261.             null));
  1262.       }
  1263.     }
  1264.     operations.push(this.enqueueOperation_(
  1265.         contentType,
  1266.         () => this.setAppendWindow_(
  1267.             contentType, appendWindowStart, appendWindowEnd),
  1268.         null));
  1269.     if (this.needSplitMuxedContent_) {
  1270.       operations.push(this.enqueueOperation_(
  1271.           ContentType.AUDIO,
  1272.           () => this.setAppendWindow_(
  1273.               ContentType.AUDIO, appendWindowStart, appendWindowEnd),
  1274.           null));
  1275.     }
  1277.     await Promise.all(operations);
  1278.   }
  1280.   /**
  1281.    * Adjust timestamp offset to maintain AV sync across discontinuities.
  1282.    *
  1283.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1284.    * @param {number} timestampOffset
  1285.    * @return {!Promise}
  1286.    */
  1287.   async resync(contentType, timestampOffset) {
  1288.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1290.     if (contentType == ContentType.TEXT) {
  1291.       // This operation is for audio and video only.
  1292.       return;
  1293.     }
  1295.     // Reset the promise in case the timestamp offset changed during
  1296.     // a period/discontinuity transition.
  1297.     if (contentType == ContentType.VIDEO) {
  1298.       this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
  1299.     }
  1301.     // Queue an abort() to help MSE splice together overlapping segments.
  1302.     // We set appendWindowEnd when we change periods in DASH content, and the
  1303.     // period transition may result in overlap.
  1304.     //
  1305.     // An abort() also helps with MPEG2-TS.  When we append a TS segment, we
  1306.     // always enter a PARSING_MEDIA_SEGMENT state and we can't change the
  1307.     // timestamp offset.  By calling abort(), we reset the state so we can
  1308.     // set it.
  1309.     this.enqueueOperation_(
  1310.         contentType,
  1311.         () => this.abort_(contentType),
  1312.         null);
  1313.     if (this.needSplitMuxedContent_) {
  1314.       this.enqueueOperation_(
  1315.           ContentType.AUDIO,
  1316.           () => this.abort_(ContentType.AUDIO),
  1317.           null);
  1318.     }
  1319.     await this.enqueueOperation_(
  1320.         contentType,
  1321.         () => this.setTimestampOffset_(contentType, timestampOffset),
  1322.         null);
  1323.     if (this.needSplitMuxedContent_) {
  1324.       await this.enqueueOperation_(
  1325.           ContentType.AUDIO,
  1326.           () => this.setTimestampOffset_(ContentType.AUDIO, timestampOffset),
  1327.           null);
  1328.     }
  1329.   }
  1331.   /**
  1332.    * @param {string=} reason Valid reasons are 'network' and 'decode'.
  1333.    * @return {!Promise}
  1334.    * @see http://w3c.github.io/media-source/#idl-def-EndOfStreamError
  1335.    */
  1336.   async endOfStream(reason) {
  1337.     await this.enqueueBlockingOperation_(() => {
  1338.       // If endOfStream() has already been called on the media source,
  1339.       // don't call it again. Also do not call if readyState is
  1340.       // 'closed' (not attached to video element) since it is not a
  1341.       // valid operation.
  1342.       if (this.ended() || this.mediaSource_.readyState === 'closed') {
  1343.         return;
  1344.       }
  1345.       // Tizen won't let us pass undefined, but it will let us omit the
  1346.       // argument.
  1347.       if (reason) {
  1348.         this.mediaSource_.endOfStream(reason);
  1349.       } else {
  1350.         this.mediaSource_.endOfStream();
  1351.       }
  1352.     });
  1353.   }
  1355.   /**
  1356.    * @param {number} duration
  1357.    * @return {!Promise}
  1358.    */
  1359.   async setDuration(duration) {
  1360.     await this.enqueueBlockingOperation_(() => {
  1361.       // Reducing the duration causes the MSE removal algorithm to run, which
  1362.       // triggers an 'updateend' event to fire.  To handle this scenario, we
  1363.       // have to insert a dummy operation into the beginning of each queue,
  1364.       // which the 'updateend' handler will remove.
  1365.       if (duration < this.mediaSource_.duration) {
  1366.         for (const contentType in this.sourceBuffers_) {
  1367.           const dummyOperation = {
  1368.             start: () => {},
  1369.             p: new shaka.util.PublicPromise(),
  1370.             uri: null,
  1371.           };
  1372.           this.queues_[contentType].unshift(dummyOperation);
  1373.         }
  1374.       }
  1376.       this.mediaSource_.duration = duration;
  1377.       this.lastDuration_ = duration;
  1378.     });
  1379.   }
  1381.   /**
  1382.    * Get the current MediaSource duration.
  1383.    *
  1384.    * @return {number}
  1385.    */
  1386.   getDuration() {
  1387.     return this.mediaSource_.duration;
  1388.   }
  1390.   /**
  1391.    * Append data to the SourceBuffer.
  1392.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1393.    * @param {BufferSource} data
  1394.    * @param {number} timestampOffset
  1395.    * @private
  1396.    */
  1397.   append_(contentType, data, timestampOffset) {
  1398.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1400.     // Append only video data to the LCEVC Dec.
  1401.     if (contentType == ContentType.VIDEO && this.lcevcDec_) {
  1402.       // Append video buffers to the LCEVC Dec for parsing and storing
  1403.       // of LCEVC data.
  1404.       this.lcevcDec_.appendBuffer(data, timestampOffset);
  1405.     }
  1407.     // This will trigger an 'updateend' event.
  1408.     this.sourceBuffers_[contentType].appendBuffer(data);
  1409.   }
  1411.   /**
  1412.    * Remove data from the SourceBuffer.
  1413.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1414.    * @param {number} startTime relative to the start of the presentation
  1415.    * @param {number} endTime relative to the start of the presentation
  1416.    * @private
  1417.    */
  1418.   remove_(contentType, startTime, endTime) {
  1419.     if (endTime <= startTime) {
  1420.       // Ignore removal of inverted or empty ranges.
  1421.       // Fake 'updateend' event to resolve the operation.
  1422.       this.onUpdateEnd_(contentType);
  1423.       return;
  1424.     }
  1426.     // This will trigger an 'updateend' event.
  1427.     this.sourceBuffers_[contentType].remove(startTime, endTime);
  1428.   }
  1430.   /**
  1431.    * Call abort() on the SourceBuffer.
  1432.    * This resets MSE's last_decode_timestamp on all track buffers, which should
  1433.    * trigger the splicing logic for overlapping segments.
  1434.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1435.    * @private
  1436.    */
  1437.   abort_(contentType) {
  1438.     // Save the append window, which is reset on abort().
  1439.     const appendWindowStart =
  1440.         this.sourceBuffers_[contentType].appendWindowStart;
  1441.     const appendWindowEnd = this.sourceBuffers_[contentType].appendWindowEnd;
  1443.     // This will not trigger an 'updateend' event, since nothing is happening.
  1444.     // This is only to reset MSE internals, not to abort an actual operation.
  1445.     this.sourceBuffers_[contentType].abort();
  1447.     // Restore the append window.
  1448.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1449.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1451.     // Fake an 'updateend' event to resolve the operation.
  1452.     this.onUpdateEnd_(contentType);
  1453.   }
  1455.   /**
  1456.    * Nudge the playhead to force the media pipeline to be flushed.
  1457.    * This seems to be necessary on Chromecast to get new content to replace old
  1458.    * content.
  1459.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1460.    * @private
  1461.    */
  1462.   flush_(contentType) {
  1463.     // Never use flush_ if there's data.  It causes a hiccup in playback.
  1464.     goog.asserts.assert(
  1465.         this.video_.buffered.length == 0, 'MediaSourceEngine.flush_ should ' +
  1466.         'only be used after clearing all data!');
  1468.     // Seeking forces the pipeline to be flushed.
  1469.     this.video_.currentTime -= 0.001;
  1471.     // Fake an 'updateend' event to resolve the operation.
  1472.     this.onUpdateEnd_(contentType);
  1473.   }
  1475.   /**
  1476.    * Set the SourceBuffer's timestamp offset.
  1477.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1478.    * @param {number} timestampOffset
  1479.    * @private
  1480.    */
  1481.   setTimestampOffset_(contentType, timestampOffset) {
  1482.     // Work around for
  1483.     // https://github.com/shaka-project/shaka-player/issues/1281:
  1484.     // TODO(https://bit.ly/2ttKiBU): follow up when this is fixed in Edge
  1485.     if (timestampOffset < 0) {
  1486.       // Try to prevent rounding errors in Edge from removing the first
  1487.       // keyframe.
  1488.       timestampOffset += 0.001;
  1489.     }
  1491.     this.sourceBuffers_[contentType].timestampOffset = timestampOffset;
  1493.     // Fake an 'updateend' event to resolve the operation.
  1494.     this.onUpdateEnd_(contentType);
  1495.   }
  1497.   /**
  1498.    * Set the SourceBuffer's append window end.
  1499.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1500.    * @param {number} appendWindowStart
  1501.    * @param {number} appendWindowEnd
  1502.    * @private
  1503.    */
  1504.   setAppendWindow_(contentType, appendWindowStart, appendWindowEnd) {
  1505.     // You can't set start > end, so first set start to 0, then set the new
  1506.     // end, then set the new start.  That way, there are no intermediate
  1507.     // states which are invalid.
  1508.     this.sourceBuffers_[contentType].appendWindowStart = 0;
  1509.     this.sourceBuffers_[contentType].appendWindowEnd = appendWindowEnd;
  1510.     this.sourceBuffers_[contentType].appendWindowStart = appendWindowStart;
  1512.     // Fake an 'updateend' event to resolve the operation.
  1513.     this.onUpdateEnd_(contentType);
  1514.   }
  1516.   /**
  1517.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1518.    * @private
  1519.    */
  1520.   onError_(contentType) {
  1521.     const operation = this.queues_[contentType][0];
  1522.     goog.asserts.assert(operation, 'Spurious error event!');
  1523.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1524.         'SourceBuffer should not be updating on error!');
  1525.     const code = this.video_.error ? this.video_.error.code : 0;
  1526.     operation.p.reject(new shaka.util.Error(
  1527.         shaka.util.Error.Severity.CRITICAL,
  1528.         shaka.util.Error.Category.MEDIA,
  1529.         shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_FAILED,
  1530.         code, operation.uri));
  1531.     // Do not pop from queue.  An 'updateend' event will fire next, and to
  1532.     // avoid synchronizing these two event handlers, we will allow that one to
  1533.     // pop from the queue as normal.  Note that because the operation has
  1534.     // already been rejected, the call to resolve() in the 'updateend' handler
  1535.     // will have no effect.
  1536.   }
  1538.   /**
  1539.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1540.    * @private
  1541.    */
  1542.   onUpdateEnd_(contentType) {
  1543.     if (this.reloadingMediaSource_) {
  1544.       return;
  1545.     }
  1546.     const operation = this.queues_[contentType][0];
  1547.     goog.asserts.assert(operation, 'Spurious updateend event!');
  1548.     if (!operation) {
  1549.       return;
  1550.     }
  1551.     goog.asserts.assert(!this.sourceBuffers_[contentType].updating,
  1552.         'SourceBuffer should not be updating on updateend!');
  1553.     operation.p.resolve();
  1554.     this.popFromQueue_(contentType);
  1555.   }
  1557.   /**
  1558.    * Enqueue an operation and start it if appropriate.
  1559.    *
  1560.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1561.    * @param {function()} start
  1562.    * @param {?string} uri
  1563.    * @return {!Promise}
  1564.    * @private
  1565.    */
  1566.   enqueueOperation_(contentType, start, uri) {
  1567.     this.destroyer_.ensureNotDestroyed();
  1568.     const operation = {
  1569.       start: start,
  1570.       p: new shaka.util.PublicPromise(),
  1571.       uri,
  1572.     };
  1573.     this.queues_[contentType].push(operation);
  1575.     if (this.queues_[contentType].length == 1) {
  1576.       this.startOperation_(contentType);
  1577.     }
  1578.     return operation.p;
  1579.   }
  1581.   /**
  1582.    * Enqueue an operation which must block all other operations on all
  1583.    * SourceBuffers.
  1584.    *
  1585.    * @param {function():(Promise|undefined)} run
  1586.    * @return {!Promise}
  1587.    * @private
  1588.    */
  1589.   async enqueueBlockingOperation_(run) {
  1590.     this.destroyer_.ensureNotDestroyed();
  1592.     /** @type {!Array.<!shaka.util.PublicPromise>} */
  1593.     const allWaiters = [];
  1595.     // Enqueue a 'wait' operation onto each queue.
  1596.     // This operation signals its readiness when it starts.
  1597.     // When all wait operations are ready, the real operation takes place.
  1598.     for (const contentType in this.sourceBuffers_) {
  1599.       const ready = new shaka.util.PublicPromise();
  1600.       const operation = {
  1601.         start: () => ready.resolve(),
  1602.         p: ready,
  1603.         uri: null,
  1604.       };
  1606.       this.queues_[contentType].push(operation);
  1607.       allWaiters.push(ready);
  1609.       if (this.queues_[contentType].length == 1) {
  1610.         operation.start();
  1611.       }
  1612.     }
  1614.     // Return a Promise to the real operation, which waits to begin until
  1615.     // there are no other in-progress operations on any SourceBuffers.
  1616.     try {
  1617.       await Promise.all(allWaiters);
  1618.     } catch (error) {
  1619.       // One of the waiters failed, which means we've been destroyed.
  1620.       goog.asserts.assert(
  1621.           this.destroyer_.destroyed(), 'Should be destroyed by now');
  1622.       // We haven't popped from the queue.  Canceled waiters have been removed
  1623.       // by destroy.  What's left now should just be resolved waiters.  In
  1624.       // uncompiled mode, we will maintain good hygiene and make sure the
  1625.       // assert at the end of destroy passes.  In compiled mode, the queues
  1626.       // are wiped in destroy.
  1627.       if (goog.DEBUG) {
  1628.         for (const contentType in this.sourceBuffers_) {
  1629.           if (this.queues_[contentType].length) {
  1630.             goog.asserts.assert(
  1631.                 this.queues_[contentType].length == 1,
  1632.                 'Should be at most one item in queue!');
  1633.             goog.asserts.assert(
  1634.                 allWaiters.includes(this.queues_[contentType][0].p),
  1635.                 'The item in queue should be one of our waiters!');
  1636.             this.queues_[contentType].shift();
  1637.           }
  1638.         }
  1639.       }
  1640.       throw error;
  1641.     }
  1643.     if (goog.DEBUG) {
  1644.       // If we did it correctly, nothing is updating.
  1645.       for (const contentType in this.sourceBuffers_) {
  1646.         goog.asserts.assert(
  1647.             this.sourceBuffers_[contentType].updating == false,
  1648.             'SourceBuffers should not be updating after a blocking op!');
  1649.       }
  1650.     }
  1652.     // Run the real operation, which can be asynchronous.
  1653.     try {
  1654.       await run();
  1655.     } catch (exception) {
  1656.       throw new shaka.util.Error(
  1657.           shaka.util.Error.Severity.CRITICAL,
  1658.           shaka.util.Error.Category.MEDIA,
  1659.           shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1660.           exception,
  1661.           this.video_.error || 'No error in the media element',
  1662.           null);
  1663.     } finally {
  1664.       // Unblock the queues.
  1665.       for (const contentType in this.sourceBuffers_) {
  1666.         this.popFromQueue_(contentType);
  1667.       }
  1668.     }
  1669.   }
  1671.   /**
  1672.    * Pop from the front of the queue and start a new operation.
  1673.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1674.    * @private
  1675.    */
  1676.   popFromQueue_(contentType) {
  1677.     // Remove the in-progress operation, which is now complete.
  1678.     this.queues_[contentType].shift();
  1679.     this.startOperation_(contentType);
  1680.   }
  1682.   /**
  1683.    * Starts the next operation in the queue.
  1684.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1685.    * @private
  1686.    */
  1687.   startOperation_(contentType) {
  1688.     // Retrieve the next operation, if any, from the queue and start it.
  1689.     const next = this.queues_[contentType][0];
  1690.     if (next) {
  1691.       try {
  1692.         next.start();
  1693.       } catch (exception) {
  1694.         if (exception.name == 'QuotaExceededError') {
  1695.           next.p.reject(new shaka.util.Error(
  1696.               shaka.util.Error.Severity.CRITICAL,
  1697.               shaka.util.Error.Category.MEDIA,
  1698.               shaka.util.Error.Code.QUOTA_EXCEEDED_ERROR,
  1699.               contentType));
  1700.         } else {
  1701.           next.p.reject(new shaka.util.Error(
  1702.               shaka.util.Error.Severity.CRITICAL,
  1703.               shaka.util.Error.Category.MEDIA,
  1704.               shaka.util.Error.Code.MEDIA_SOURCE_OPERATION_THREW,
  1705.               exception,
  1706.               this.video_.error || 'No error in the media element',
  1707.               next.uri));
  1708.         }
  1709.         this.popFromQueue_(contentType);
  1710.       }
  1711.     }
  1712.   }
  1714.   /**
  1715.    * @return {!shaka.extern.TextDisplayer}
  1716.    */
  1717.   getTextDisplayer() {
  1718.     goog.asserts.assert(
  1719.         this.textDisplayer_,
  1720.         'TextDisplayer should only be null when this is destroyed');
  1722.     return this.textDisplayer_;
  1723.   }
  1725.   /**
  1726.    * @param {!shaka.extern.TextDisplayer} textDisplayer
  1727.    */
  1728.   setTextDisplayer(textDisplayer) {
  1729.     const oldTextDisplayer = this.textDisplayer_;
  1730.     this.textDisplayer_ = textDisplayer;
  1731.     if (oldTextDisplayer) {
  1732.       textDisplayer.setTextVisibility(oldTextDisplayer.isTextVisible());
  1733.       oldTextDisplayer.destroy();
  1734.     }
  1735.     if (this.textEngine_) {
  1736.       this.textEngine_.setDisplayer(textDisplayer);
  1737.     }
  1738.   }
  1740.   /**
  1741.    * @param {boolean} segmentRelativeVttTiming
  1742.    */
  1743.   setSegmentRelativeVttTiming(segmentRelativeVttTiming) {
  1744.     this.segmentRelativeVttTiming_ = segmentRelativeVttTiming;
  1745.   }
  1747.   /**
  1748.    * Apply platform-specific transformations to this segment to work around
  1749.    * issues in the platform.
  1750.    *
  1751.    * @param {!BufferSource} segment
  1752.    * @param {?number} startTime
  1753.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1754.    * @param {?string} uri
  1755.    * @return {!BufferSource}
  1756.    * @private
  1757.    */
  1758.   workAroundBrokenPlatforms_(segment, startTime, contentType, uri) {
  1759.     const Platform = shaka.util.Platform;
  1761.     const isInitSegment = startTime == null;
  1762.     const encryptionExpected = this.expectedEncryption_[contentType];
  1763.     const keySystem = this.playerInterface_.getKeySystem();
  1765.     // If:
  1766.     //   1. the configuration tells to insert fake encryption,
  1767.     //   2. and this is an init segment,
  1768.     //   3. and encryption is expected,
  1769.     //   4. and the platform requires encryption in all init segments,
  1770.     //   5. and the content is MP4 (mimeType == "video/mp4" or "audio/mp4"),
  1771.     // then insert fake encryption metadata for init segments that lack it.
  1772.     // The MP4 requirement is because we can currently only do this
  1773.     // transformation on MP4 containers.
  1774.     // See: https://github.com/shaka-project/shaka-player/issues/2759
  1775.     if (this.config_.insertFakeEncryptionInInit &&
  1776.         isInitSegment &&
  1777.         encryptionExpected &&
  1778.         Platform.requiresEncryptionInfoInAllInitSegments(keySystem) &&
  1779.         shaka.util.MimeUtils.getContainerType(
  1780.             this.sourceBufferTypes_[contentType]) == 'mp4') {
  1781.       shaka.log.debug('Forcing fake encryption information in init segment.');
  1782.       segment = shaka.media.ContentWorkarounds.fakeEncryption(segment, uri);
  1783.     }
  1785.     return segment;
  1786.   }
  1788.   /**
  1789.    * Prepare the SourceBuffer to parse a potentially new type or codec.
  1790.    *
  1791.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1792.    * @param {string} mimeType
  1793.    * @param {?shaka.extern.Transmuxer} transmuxer
  1794.    * @private
  1795.    */
  1796.   change_(contentType, mimeType, transmuxer) {
  1797.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1798.     if (contentType === ContentType.TEXT) {
  1799.       shaka.log.debug(`Change not supported for ${contentType}`);
  1800.       return;
  1801.     }
  1802.     shaka.log.debug(
  1803.         `Change Type: ${this.sourceBufferTypes_[contentType]} -> ${mimeType}`);
  1804.     if (shaka.media.Capabilities.isChangeTypeSupported()) {
  1805.       if (this.transmuxers_[contentType]) {
  1806.         this.transmuxers_[contentType].destroy();
  1807.         delete this.transmuxers_[contentType];
  1808.       }
  1809.       if (transmuxer) {
  1810.         this.transmuxers_[contentType] = transmuxer;
  1811.       }
  1812.       const type = this.addExtraFeaturesToMimeType_(mimeType);
  1813.       this.sourceBuffers_[contentType].changeType(type);
  1814.       this.sourceBufferTypes_[contentType] = mimeType;
  1815.     } else {
  1816.       shaka.log.debug('Change Type not supported');
  1817.     }
  1819.     // Fake an 'updateend' event to resolve the operation.
  1820.     this.onUpdateEnd_(contentType);
  1821.   }
  1823.   /**
  1824.    * Enqueue an operation to prepare the SourceBuffer to parse a potentially new
  1825.    * type or codec.
  1826.    *
  1827.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1828.    * @param {string} mimeType
  1829.    * @param {?shaka.extern.Transmuxer} transmuxer
  1830.    * @return {!Promise}
  1831.    */
  1832.   changeType(contentType, mimeType, transmuxer) {
  1833.     return this.enqueueOperation_(
  1834.         contentType,
  1835.         () => this.change_(contentType, mimeType, transmuxer),
  1836.         null);
  1837.   }
  1839.   /**
  1840.    * Resets the MediaSource and re-adds source buffers due to codec mismatch
  1841.    *
  1842.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1843.    *               shaka.extern.Stream>} streamsByType
  1844.    * @private
  1845.    */
  1846.   async reset_(streamsByType) {
  1847.     const Functional = shaka.util.Functional;
  1848.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1849.     this.reloadingMediaSource_ = true;
  1850.     this.needSplitMuxedContent_ = false;
  1851.     const currentTime = this.video_.currentTime;
  1853.     // When codec switching if the user is currently paused we don't want
  1854.     // to trigger a play when switching codec.
  1855.     // Playing can also end up in a paused state after a codec switch
  1856.     // so we need to remember the current states.
  1857.     const previousAutoPlayState = this.video_.autoplay;
  1858.     const previousPausedState = this.video_.paused;
  1859.     if (this.playbackHasBegun_) {
  1860.       // Only set autoplay to false if the video playback has already begun.
  1861.       // When a codec switch happens before playback has begun this can cause
  1862.       // autoplay not to work as expected.
  1863.       this.video_.autoplay = false;
  1864.     }
  1866.     try {
  1867.       this.eventManager_.removeAll();
  1869.       const cleanup = [];
  1870.       for (const contentType in this.transmuxers_) {
  1871.         cleanup.push(this.transmuxers_[contentType].destroy());
  1872.       }
  1873.       for (const contentType in this.queues_) {
  1874.         // Make a local copy of the queue and the first item.
  1875.         const q = this.queues_[contentType];
  1876.         const inProgress = q[0];
  1878.         // Drop everything else out of the original queue.
  1879.         this.queues_[contentType] = q.slice(0, 1);
  1881.         // We will wait for this item to complete/fail.
  1882.         if (inProgress) {
  1883.           cleanup.push(inProgress.p.catch(Functional.noop));
  1884.         }
  1886.         // The rest will be rejected silently if possible.
  1887.         for (const item of q.slice(1)) {
  1888.           item.p.reject(shaka.util.Destroyer.destroyedError());
  1889.         }
  1890.       }
  1891.       for (const contentType in this.sourceBuffers_) {
  1892.         const sourceBuffer = this.sourceBuffers_[contentType];
  1893.         try {
  1894.           this.mediaSource_.removeSourceBuffer(sourceBuffer);
  1895.         } catch (e) {}
  1896.       }
  1897.       await Promise.all(cleanup);
  1898.       this.transmuxers_ = {};
  1899.       this.sourceBuffers_ = {};
  1901.       const previousDuration = this.mediaSource_.duration;
  1902.       this.mediaSourceOpen_ = new shaka.util.PublicPromise();
  1903.       this.mediaSource_ = this.createMediaSource(this.mediaSourceOpen_);
  1904.       await this.mediaSourceOpen_;
  1905.       if (!isNaN(previousDuration) && previousDuration) {
  1906.         this.mediaSource_.duration = previousDuration;
  1907.       } else if (!isNaN(this.lastDuration_) && this.lastDuration_) {
  1908.         this.mediaSource_.duration = this.lastDuration_;
  1909.       }
  1911.       const sourceBufferAdded = new shaka.util.PublicPromise();
  1912.       const sourceBuffers =
  1913.         /** @type {EventTarget} */(this.mediaSource_.sourceBuffers);
  1915.       const totalOfBuffers = streamsByType.size;
  1916.       let numberOfSourceBufferAdded = 0;
  1917.       const onSourceBufferAdded = () => {
  1918.         numberOfSourceBufferAdded++;
  1919.         if (numberOfSourceBufferAdded === totalOfBuffers) {
  1920.           sourceBufferAdded.resolve();
  1921.           this.eventManager_.unlisten(sourceBuffers, 'addsourcebuffer',
  1922.               onSourceBufferAdded);
  1923.         }
  1924.       };
  1926.       this.eventManager_.listen(sourceBuffers, 'addsourcebuffer',
  1927.           onSourceBufferAdded);
  1929.       for (const contentType of streamsByType.keys()) {
  1930.         const stream = streamsByType.get(contentType);
  1931.         // eslint-disable-next-line no-await-in-loop
  1932.         await this.initSourceBuffer_(contentType, stream, stream.codecs);
  1933.         if (this.needSplitMuxedContent_) {
  1934.           this.queues_[ContentType.AUDIO] = [];
  1935.           this.queues_[ContentType.VIDEO] = [];
  1936.         } else {
  1937.           this.queues_[contentType] = [];
  1938.         }
  1939.       }
  1941.       // Fake a seek to catchup the playhead.
  1942.       this.video_.currentTime = currentTime;
  1944.       await sourceBufferAdded;
  1945.     } finally {
  1946.       this.reloadingMediaSource_ = false;
  1948.       this.destroyer_.ensureNotDestroyed();
  1950.       this.eventManager_.listenOnce(this.video_, 'canplaythrough', () => {
  1951.         // Don't use ensureNotDestroyed() from this event listener, because
  1952.         // that results in an uncaught exception.  Instead, just check the
  1953.         // flag.
  1954.         if (this.destroyer_.destroyed()) {
  1955.           return;
  1956.         }
  1958.         this.video_.autoplay = previousAutoPlayState;
  1959.         if (!previousPausedState) {
  1960.           this.video_.play();
  1961.         }
  1962.       });
  1963.     }
  1964.   }
  1966.   /**
  1967.    * Resets the Media Source
  1968.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1969.    *               shaka.extern.Stream>} streamsByType
  1970.    * @return {!Promise}
  1971.    */
  1972.   reset(streamsByType) {
  1973.     return this.enqueueBlockingOperation_(
  1974.         () => this.reset_(streamsByType));
  1975.   }
  1977.   /**
  1978.    * Codec switch if necessary, this will not resolve until the codec
  1979.    * switch is over.
  1980.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  1981.    * @param {string} mimeType
  1982.    * @param {string} codecs
  1983.    * @param {!Map.<shaka.util.ManifestParserUtils.ContentType,
  1984.    *               shaka.extern.Stream>} streamsByType
  1985.    * @return {!Promise.<boolean>} true if there was a codec switch,
  1986.    *                              false otherwise.
  1987.    * @private
  1988.    */
  1989.   async codecSwitchIfNecessary_(contentType, mimeType, codecs, streamsByType) {
  1990.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1991.     if (contentType == ContentType.TEXT) {
  1992.       return false;
  1993.     }
  1994.     const MimeUtils = shaka.util.MimeUtils;
  1995.     const currentCodec = MimeUtils.getCodecBase(
  1996.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  1997.     const currentBasicType = MimeUtils.getBasicType(
  1998.         this.sourceBufferTypes_[contentType]);
  2000.     /** @type {?shaka.extern.Transmuxer} */
  2001.     let transmuxer;
  2002.     let transmuxerMuxed = false;
  2003.     let newMimeType = shaka.util.MimeUtils.getFullType(mimeType, codecs);
  2004.     let needTransmux = this.config_.forceTransmux;
  2005.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2006.         (!this.sequenceMode_ &&
  2007.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2008.       needTransmux = true;
  2009.     }
  2010.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2011.     if (needTransmux) {
  2012.       const newMimeTypeWithAllCodecs =
  2013.           shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codecs);
  2014.       const transmuxerPlugin =
  2015.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2016.       if (transmuxerPlugin) {
  2017.         transmuxer = transmuxerPlugin();
  2018.         const audioCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2019.             ContentType.AUDIO, (codecs || '').split(','));
  2020.         const videoCodec = shaka.util.ManifestParserUtils.guessCodecsSafe(
  2021.             ContentType.VIDEO, (codecs || '').split(','));
  2022.         if (audioCodec && videoCodec) {
  2023.           transmuxerMuxed = true;
  2024.           let codec = videoCodec;
  2025.           if (contentType == ContentType.AUDIO) {
  2026.             codec = audioCodec;
  2027.           }
  2028.           newMimeType = transmuxer.convertCodecs(contentType,
  2029.               shaka.util.MimeUtils.getFullTypeWithAllCodecs(mimeType, codec));
  2030.         } else {
  2031.           newMimeType =
  2032.               transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2033.         }
  2034.       }
  2035.     }
  2037.     const newCodec = MimeUtils.getCodecBase(
  2038.         MimeUtils.getCodecs(newMimeType));
  2039.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2041.     // Current/new codecs base and basic type match then no need to switch
  2042.     if (currentCodec === newCodec && currentBasicType === newBasicType) {
  2043.       return false;
  2044.     }
  2046.     let allowChangeType = true;
  2047.     if (this.needSplitMuxedContent_ || (transmuxerMuxed &&
  2048.         transmuxer && !this.transmuxers_[contentType])) {
  2049.       allowChangeType = false;
  2050.     }
  2052.     if (allowChangeType && this.config_.codecSwitchingStrategy ===
  2053.         shaka.config.CodecSwitchingStrategy.SMOOTH &&
  2054.           shaka.media.Capabilities.isChangeTypeSupported()) {
  2055.       await this.changeType(contentType, newMimeType, transmuxer);
  2056.     } else {
  2057.       if (transmuxer) {
  2058.         transmuxer.destroy();
  2059.       }
  2060.       await this.reset(streamsByType);
  2061.     }
  2062.     return true;
  2063.   }
  2065.   /**
  2066.    * Returns true if it's necessary codec switch to load the new stream.
  2067.    *
  2068.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2069.    * @param {shaka.extern.Stream} stream
  2070.    * @param {string} refMimeType
  2071.    * @param {string} refCodecs
  2072.    * @return {boolean}
  2073.    * @private
  2074.    */
  2075.   isCodecSwitchNecessary_(contentType, stream, refMimeType, refCodecs) {
  2076.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2077.       return false;
  2078.     }
  2079.     const MimeUtils = shaka.util.MimeUtils;
  2080.     const currentCodec = MimeUtils.getCodecBase(
  2081.         MimeUtils.getCodecs(this.sourceBufferTypes_[contentType]));
  2082.     const currentBasicType = MimeUtils.getBasicType(
  2083.         this.sourceBufferTypes_[contentType]);
  2085.     let newMimeType = shaka.util.MimeUtils.getFullType(refMimeType, refCodecs);
  2086.     let needTransmux = this.config_.forceTransmux;
  2087.     if (!shaka.media.Capabilities.isTypeSupported(newMimeType) ||
  2088.         (!this.sequenceMode_ &&
  2089.         shaka.util.MimeUtils.RAW_FORMATS.includes(newMimeType))) {
  2090.       needTransmux = true;
  2091.     }
  2092.     const newMimeTypeWithAllCodecs =
  2093.         shaka.util.MimeUtils.getFullTypeWithAllCodecs(
  2094.             refMimeType, refCodecs);
  2095.     const TransmuxerEngine = shaka.transmuxer.TransmuxerEngine;
  2096.     if (needTransmux) {
  2097.       const transmuxerPlugin =
  2098.           TransmuxerEngine.findTransmuxer(newMimeTypeWithAllCodecs);
  2099.       if (transmuxerPlugin) {
  2100.         const transmuxer = transmuxerPlugin();
  2101.         newMimeType =
  2102.             transmuxer.convertCodecs(contentType, newMimeTypeWithAllCodecs);
  2103.         transmuxer.destroy();
  2104.       }
  2105.     }
  2107.     const newCodec = MimeUtils.getCodecBase(
  2108.         MimeUtils.getCodecs(newMimeType));
  2109.     const newBasicType = MimeUtils.getBasicType(newMimeType);
  2111.     return currentCodec !== newCodec || currentBasicType !== newBasicType;
  2112.   }
  2114.   /**
  2115.    * Returns true if it's necessary reset the media source to load the
  2116.    * new stream.
  2117.    *
  2118.    * @param {shaka.util.ManifestParserUtils.ContentType} contentType
  2119.    * @param {shaka.extern.Stream} stream
  2120.    * @param {string} mimeType
  2121.    * @param {string} codecs
  2122.    * @return {boolean}
  2123.    */
  2124.   isResetMediaSourceNecessary(contentType, stream, mimeType, codecs) {
  2125.     if (!this.isCodecSwitchNecessary_(contentType, stream, mimeType, codecs)) {
  2126.       return false;
  2127.     }
  2129.     return this.config_.codecSwitchingStrategy !==
  2130.         shaka.config.CodecSwitchingStrategy.SMOOTH ||
  2131.         !shaka.media.Capabilities.isChangeTypeSupported() ||
  2132.         this.needSplitMuxedContent_;
  2133.   }
  2135.   /**
  2136.    * Update LCEVC Decoder object when ready for LCEVC Decode.
  2137.    * @param {?shaka.lcevc.Dec} lcevcDec
  2138.    */
  2139.   updateLcevcDec(lcevcDec) {
  2140.     this.lcevcDec_ = lcevcDec;
  2141.   }
  2143.   /**
  2144.    * @param {string} mimeType
  2145.    * @return {string}
  2146.    * @private
  2147.    */
  2148.   addExtraFeaturesToMimeType_(mimeType) {
  2149.     const extraFeatures = this.config_.addExtraFeaturesToSourceBuffer(mimeType);
  2150.     const extendedType = mimeType + extraFeatures;
  2151.     shaka.log.debug('Using full mime type', extendedType);
  2153.     return extendedType;
  2154.   }
  2155. };
  2158. /**
  2159.  * Internal reference to window.URL.createObjectURL function to avoid
  2160.  * compatibility issues with other libraries and frameworks such as React
  2161.  * Native. For use in unit tests only, not meant for external use.
  2162.  *
  2163.  * @type {function(?):string}
  2164.  */
  2165. shaka.media.MediaSourceEngine.createObjectURL = window.URL.createObjectURL;
  2168. /**
  2169.  * @typedef {{
  2170.  *   start: function(),
  2171.  *   p: !shaka.util.PublicPromise,
  2172.  *   uri: ?string
  2173.  * }}
  2174.  *
  2175.  * @summary An operation in queue.
  2176.  * @property {function()} start
  2177.  *   The function which starts the operation.
  2178.  * @property {!shaka.util.PublicPromise} p
  2179.  *   The PublicPromise which is associated with this operation.
  2180.  * @property {?string} uri
  2181.  *   A segment URI (if any) associated with this operation.
  2182.  */
  2183. shaka.media.MediaSourceEngine.Operation;
  2186. /**
  2187.  * @enum {string}
  2188.  * @private
  2189.  */
  2190. shaka.media.MediaSourceEngine.SourceBufferMode_ = {
  2191.   SEQUENCE: 'sequence',
  2192.   SEGMENTS: 'segments',
  2193. };
  2196. /**
  2197.  * @typedef {{
  2198.  *   getKeySystem: function():?string,
  2199.  *   onMetadata: function(!Array<shaka.extern.ID3Metadata>, number, ?number)
  2200.  * }}
  2201.  *
  2202.  * @summary Player interface
  2203.  * @property {function():?string} getKeySystem
  2204.  *   Gets currently used key system or null if not used.
  2205.  * @property {function(
  2206.  *     !Array<shaka.extern.ID3Metadata>, number, ?number)} onMetadata
  2207.  *   Callback to use when metadata arrives.
  2208.  */
  2209. shaka.media.MediaSourceEngine.PlayerInterface;