Align with 3-5-2

README.md

@@ -463,12 +463,6 @@ This option defaults to `false`.
 * Default: `false`
 * Use [Decode Timestamp](https://www.w3.org/TR/media-source/#decode-timestamp) instead of [Presentation Timestamp](https://www.w3.org/TR/media-source/#presentation-timestamp) for [timestampOffset](https://www.w3.org/TR/media-source/#dom-sourcebuffer-timestampoffset) calculation. This option was introduced to align with DTS-based browsers. This option affects only transmuxed data (eg: transport stream). For more info please check the following [issue](https://github.com/videojs/http-streaming/issues/1247).  
 
-##### calculateTimestampOffsetForEachSegment
-* Type: `boolean`,
-* Default: `false`
-* Calculate timestampOffset for each segment, regardless of its timeline. Sometimes it is helpful when you have corrupted DTS/PTS timestamps during discontinuities.
-
-
 ##### useForcedSubtitles
 * Type: `boolean`
 * Default: `false`

index.html

@@ -144,11 +144,6 @@
           <label class="form-check-label" for="dts-offset">Use DTS instead of PTS for Timestamp Offset calculation (reloads player)</label>
         </div>
 
-        <div class="form-check">
-          <input id=offset-each-segment type="checkbox" class="form-check-input">
-          <label class="form-check-label" for="offset-each-segment">Calculate timestampOffset for each segment, regardless of its timeline (reloads player)</label>
-        </div>
-
         <div class="form-check">
           <input id=llhls type="checkbox" class="form-check-input">
           <label class="form-check-label" for="llhls">[EXPERIMENTAL] Enables support for ll-hls (reloads player)</label>

scripts/index.js

@@ -470,7 +470,6 @@
     'pixel-diff-selector',
     'network-info',
     'dts-offset',
-    'offset-each-segment',
     'override-native',
     'preload',
     'mirror-source',
@@ -526,7 +525,6 @@
       'pixel-diff-selector',
       'network-info',
       'dts-offset',
-      'offset-each-segment',
       'exact-manifest-timings',
       'forced-subtitles'
     ].forEach(function(name) {
@@ -611,7 +609,6 @@
               leastPixelDiffSelector: getInputValue(stateEls['pixel-diff-selector']),
               useNetworkInformationApi: getInputValue(stateEls['network-info']),
               useDtsForTimestampOffset: getInputValue(stateEls['dts-offset']),
-              calculateTimestampOffsetForEachSegment: getInputValue(stateEls['offset-each-segment']),
               useForcedSubtitles: getInputValue(stateEls['forced-subtitles'])
             }
           }

src/playlist-controller.js

@@ -240,7 +240,6 @@ export class PlaylistController extends videojs.EventTarget {
       vhs: this.vhs_,
       parse708captions: options.parse708captions,
       useDtsForTimestampOffset: options.useDtsForTimestampOffset,
-      calculateTimestampOffsetForEachSegment: options.calculateTimestampOffsetForEachSegment,
       captionServices,
       mediaSource: this.mediaSource,
       currentTime: this.tech_.currentTime.bind(this.tech_),
@@ -682,9 +681,14 @@ export class PlaylistController extends videojs.EventTarget {
       // that the segments have changed in some way and use that to
       // update the SegmentLoader instead of doing it twice here and
       // on `loadedplaylist`
+      this.mainSegmentLoader_.pause();
       this.mainSegmentLoader_.playlist(media, this.requestOptions_);
 
-      this.mainSegmentLoader_.load();
+      if (this.waitingForFastQualityPlaylistReceived_) {
+        this.runFastQualitySwitch_();
+      } else {
+        this.mainSegmentLoader_.load();
+      }
 
       this.tech_.trigger({
         type: 'mediachange',
@@ -746,7 +750,12 @@ export class PlaylistController extends videojs.EventTarget {
     // that the segments have changed in some way and use that to
     // update the SegmentLoader instead of doing it twice here and
     // on `mediachange`
+    this.mainSegmentLoader_.pause();
     this.mainSegmentLoader_.playlist(updatedPlaylist, this.requestOptions_);
+    if (this.waitingForFastQualityPlaylistReceived_) {
+      this.runFastQualitySwitch_();
+    }
+
     this.updateDuration(!updatedPlaylist.endList);
 
     // If the player isn't paused, ensure that the segment loader is running,
@@ -961,9 +970,9 @@ export class PlaylistController extends videojs.EventTarget {
 
   /**
    * Re-tune playback quality level for the current player
-   * conditions. This will reset the main segment loader
-   * and the next segment position to the currentTime.
-   * This is good for manual quality changes.
+   * conditions. This method will perform destructive actions like removing
+   * already buffered content in order to readjust the currently active
+   * playlist quickly. This is good for manual quality changes
    *
    * @private
    */
@@ -972,28 +981,28 @@ export class PlaylistController extends videojs.EventTarget {
       this.logger_('skipping fastQualityChange because new media is same as old');
       return;
     }
+
     this.switchMedia_(media, 'fast-quality');
-    // Reset main segment loader properties and next segment position information.
-    // Don't need to reset audio as it is reset when media changes.
-    // We resetLoaderProperties separately here as we want to fetch init segments if
-    // necessary and ensure we're not in an ended state when we switch playlists.
-    this.resetMainLoaderReplaceSegments();
-  }
 
-  /**
-   * Sets the replaceUntil flag on the main segment soader to the buffered end
-   * and resets the main segment loaders properties.
-   */
-  resetMainLoaderReplaceSegments() {
-    const buffered = this.tech_.buffered();
-    const bufferedEnd = buffered.length ? buffered.end(buffered.length - 1) : 0;
+    // we would like to avoid race condition when we call fastQuality,
+    // reset everything and start loading segments from prev segments instead of new because new playlist is not received yet
+    this.waitingForFastQualityPlaylistReceived_ = true;
+  }
+
+  runFastQualitySwitch_() {
+    this.waitingForFastQualityPlaylistReceived_ = false;
+    // Delete all buffered data to allow an immediate quality switch, then seek to give
+    // the browser a kick to remove any cached frames from the previous rendtion (.04 seconds
+    // ahead was roughly the minimum that will accomplish this across a variety of content
+    // in IE and Edge, but seeking in place is sufficient on all other browsers)
+    // Edge/IE bug: https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/14600375/
+    // Chrome bug: https://bugs.chromium.org/p/chromium/issues/detail?id=651904
+    this.mainSegmentLoader_.pause();
+    this.mainSegmentLoader_.resetEverything(() => {
+      this.tech_.setCurrentTime(this.tech_.currentTime());
+    });
 
-    // Set the replace segments flag to the buffered end, this forces fetchAtBuffer
-    // on the main loader to remain, false after the resetLoader call, until we have
-    // replaced all content buffered ahead of the currentTime.
-    this.mainSegmentLoader_.replaceSegmentsUntil = bufferedEnd;
-    this.mainSegmentLoader_.resetLoaderProperties();
-    this.mainSegmentLoader_.resetLoader();
+    // don't need to reset audio as it is reset when media changes
   }
 
   /**
@@ -1455,11 +1464,14 @@ export class PlaylistController extends videojs.EventTarget {
 
     // cancel outstanding requests so we begin buffering at the new
     // location
+    this.mainSegmentLoader_.pause();
     this.mainSegmentLoader_.resetEverything();
     if (this.mediaTypes_.AUDIO.activePlaylistLoader) {
+      this.audioSegmentLoader_.pause();
       this.audioSegmentLoader_.resetEverything();
     }
     if (this.mediaTypes_.SUBTITLES.activePlaylistLoader) {
+      this.subtitleSegmentLoader_.pause();
       this.subtitleSegmentLoader_.resetEverything();
     }