Fix MSS live seeking (#3574)

* [MSS] fix segment timeline update according to DVR window

* [MSS] reset MSSHandler first

* [MSS] never abort FragmentInfo requests

* [MSS] seek to DVR window range start in case DVR window is updating while seeking to range start

* [MSS] do not set availabilityStartTime

* [MSS] fix FragmentInfo requests timing in case of Precondition failed (start global timer once first FragmentInfo request has been received)

* [MSS] update DVR window range only for audio and video tracks

* [MSS] Ignore FragmentInfo requests errors

* PlaybackController: in updateCurrentTime, check if not already seeking when seeking back to DVR window start

* Settings: allow for setting non-existing(declared) values

* [MSS] set retry attempts and intervals for FragmentInfo requests

* [MSS] do not remove segment from timeline (DVR window) if currently playing

* [MSS] Add HTTPRequest type for FragmentInfo segments

* [MSS] add retryAttempts and retryIntreval for FragmentInfo requests

* Revert "Settings: allow for setting non-existing(declared) values"

This reverts commit d0a3a1a.

* complete Settings jsdoc

* clean code

index.d.ts

@@ -187,6 +187,7 @@ declare namespace dashjs {
                 'InitializationSegment'?:     number;
                 'BitstreamSwitchingSegment'?: number;
                 'IndexSegment'?:              number;
+                'FragmentInfoSegment'?:       number;
                 'other'?:                     number;
                 'lowLatencyReductionFactor'?:  number;
             };
@@ -197,6 +198,7 @@ declare namespace dashjs {
                 'InitializationSegment'?:     number;
                 'BitstreamSwitchingSegment'?: number;
                 'IndexSegment'?:              number;
+                'FragmentInfoSegment'?:       number;
                 'other'?:                     number;
                 'lowLatencyMultiplyFactor'?:  number;
             };

src/core/Settings.js

@@ -121,6 +121,7 @@ import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
  *              IndexSegment: 1000,
  *              MediaSegment: 1000,
  *              BitstreamSwitchingSegment: 1000,
+ *              FragmentInfoSegment: 1000,
  *              other: 1000,
  *              lowLatencyReductionFactor: 10
  *          },
@@ -131,6 +132,7 @@ import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
  *              IndexSegment: 3,
  *              MediaSegment: 3,
  *              BitstreamSwitchingSegment: 3,
+ *              FragmentInfoSegment: 3,
  *              other: 3,
  *              lowLatencyMultiplyFactor: 5
  *          },
@@ -462,6 +464,8 @@ import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
  * Request to retrieve a media segment (video/audio/image/text chunk).
  * @property {number} [BitstreamSwitchingSegment]
  * Bitrate stream switching type of request.
+ * @property {number} [FragmentInfoSegment]
+ * Request to retrieve a FragmentInfo segment (specific to Smooth Streaming live streams).
  * @property {number} [other]
  * Other type of request.
  * @property {number} [lowLatencyReductionFactor]
@@ -672,6 +676,7 @@ function Settings() {
                 [HTTPRequest.INIT_SEGMENT_TYPE]: 1000,
                 [HTTPRequest.BITSTREAM_SWITCHING_SEGMENT_TYPE]: 1000,
                 [HTTPRequest.INDEX_SEGMENT_TYPE]: 1000,
+                [HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE]: 1000,
                 [HTTPRequest.OTHER_TYPE]: 1000,
                 lowLatencyReductionFactor: 10
             },
@@ -682,6 +687,7 @@ function Settings() {
                 [HTTPRequest.INIT_SEGMENT_TYPE]: 3,
                 [HTTPRequest.BITSTREAM_SWITCHING_SEGMENT_TYPE]: 3,
                 [HTTPRequest.INDEX_SEGMENT_TYPE]: 3,
+                [HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE]: 3,
                 [HTTPRequest.OTHER_TYPE]: 3,
                 lowLatencyMultiplyFactor: 5
             },

src/mss/MssFragmentInfoController.js

@@ -30,6 +30,7 @@
  */
 
 import FragmentRequest from '../streaming/vo/FragmentRequest';
+import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
 
 function MssFragmentInfoController(config) {
 
@@ -69,7 +70,6 @@ function MssFragmentInfoController(config) {
         logger.debug('Start');
 
         started = true;
-        startTime = new Date().getTime();
         index = 0;
 
         loadNextFragmentInfo();
@@ -114,7 +114,7 @@ function MssFragmentInfoController(config) {
         let request = new FragmentRequest();
 
         request.mediaType = type;
-        request.type = 'FragmentInfoSegment';
+        request.type = HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE;
         // request.range = segment.mediaRange;
         request.startTime = segment.t / timescale;
         request.duration = segment.d / timescale;
@@ -168,6 +168,10 @@ function MssFragmentInfoController(config) {
 
         // logger.debug('FragmentInfo loaded: ', request.url);
 
+        if (startTime === null) {
+            startTime = new Date().getTime();
+        }
+
         if (!startFragmentTime) {
             startFragmentTime = request.startTime;
         }

src/mss/MssFragmentMoofProcessor.js

@@ -84,6 +84,7 @@ function MssFragmentMoofProcessor(config) {
             range;
         let segment = null;
         let t = 0;
+        let endTime;
         let availabilityStartTime = null;
 
         if (entries.length === 0) {
@@ -144,9 +145,9 @@ function MssFragmentMoofProcessor(config) {
         if (manifest.type === 'static') {
             if (type === 'video') {
                 segment = segments[segments.length - 1];
-                var end = (segment.t + segment.d) / timescale;
-                if (end > representation.adaptation.period.duration) {
-                    eventBus.trigger(Events.MANIFEST_VALIDITY_CHANGED, { sender: this, newDuration: end });
+                endTime = (segment.t + segment.d) / timescale;
+                if (endTime > representation.adaptation.period.duration) {
+                    eventBus.trigger(Events.MANIFEST_VALIDITY_CHANGED, { sender: this, newDuration: endTime });
                 }
             }
             return;
@@ -159,14 +160,20 @@ function MssFragmentMoofProcessor(config) {
                 t = segment.t;
 
                 // Determine the segments' availability start time
-                availabilityStartTime = Math.round((t - (manifest.timeShiftBufferDepth * timescale)) / timescale);
+                availabilityStartTime = (t - (manifest.timeShiftBufferDepth * timescale)) / timescale;
 
                 // Remove segments prior to availability start time
                 segment = segments[0];
-                while (Math.round(segment.t / timescale) < availabilityStartTime) {
+                endTime = (segment.t + segment.d) / timescale;
+                while (endTime < availabilityStartTime) {
+                    // Check if not currently playing the segment to be removed
+                    if (!playbackController.isPaused() && playbackController.getTime() < endTime) {
+                        break;
+                    }
                     // logger.debug('Remove segment  - t = ' + (segment.t / timescale));
                     segments.splice(0, 1);
                     segment = segments[0];
+                    endTime =  (segment.t + segment.d) / timescale;
                 }
             }
 
@@ -183,10 +190,12 @@ function MssFragmentMoofProcessor(config) {
     }
 
     function updateDVR(type, range, manifestInfo) {
+        if (type !== 'video' && type !== 'audio') return;
         const dvrInfos = dashMetrics.getCurrentDVRInfo(type);
         if (!dvrInfos || (range.end > dvrInfos.range.end)) {
             logger.debug('Update DVR range: [' + range.start + ' - ' + range.end + ']');
             dashMetrics.addDVRInfo(type, playbackController.getTime(), manifestInfo, range);
+            playbackController.updateCurrentTime(type);
         }
     }
 

src/mss/MssFragmentProcessor.js

@@ -31,6 +31,8 @@
 
 import MssFragmentMoofProcessor from './MssFragmentMoofProcessor';
 import MssFragmentMoovProcessor from './MssFragmentMoovProcessor';
+import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
+
 
 // Add specific box processors not provided by codem-isoboxer library
 
@@ -163,7 +165,7 @@ function MssFragmentProcessor(config) {
             // MediaSegment => convert to Smooth Streaming moof format
             mssFragmentMoofProcessor.convertFragment(e, streamProcessor);
 
-        } else if (e.request.type === 'FragmentInfoSegment') {
+        } else if (e.request.type === HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE) {
             // FragmentInfo (live) => update segments list
             mssFragmentMoofProcessor.updateSegmentList(e, streamProcessor);
 

src/mss/MssHandler.js

@@ -37,6 +37,7 @@ import MssParser from './parser/MssParser';
 import MssErrors from './errors/MssErrors';
 import DashJSError from '../streaming/vo/DashJSError';
 import InitCache from '../streaming/utils/InitCache';
+import {HTTPRequest} from '../streaming/vo/metrics/HTTPRequest';
 
 function MssHandler(config) {
 
@@ -176,7 +177,7 @@ function MssHandler(config) {
         // Process moof to transcode it from MSS to DASH (or to update segment timeline for SegmentInfo fragments)
         mssFragmentProcessor.processFragment(e, streamProcessor);
 
-        if (e.request.type === 'FragmentInfoSegment') {
+        if (e.request.type === HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE) {
             // If FragmentInfo loaded, then notify corresponding MssFragmentInfoController
             let fragmentInfoController = getFragmentInfoController(e.request.mediaType);
             if (fragmentInfoController) {

src/mss/parser/MssParser.js

@@ -592,7 +592,7 @@ function MssParser(config) {
         return widevineCP;
     }
 
-    function processManifest(xmlDoc, manifestLoadedTime) {
+    function processManifest(xmlDoc) {
         const manifest = {};
         const contentProtections = [];
         const smoothStreamingMedia = xmlDoc.getElementsByTagName('SmoothStreamingMedia')[0];
@@ -706,11 +706,6 @@ function MssParser(config) {
                 manifest.minBufferTime = segmentDuration;
 
                 if (manifest.type === 'dynamic' ) {
-                    // Set availabilityStartTime
-                    segments = adaptations[i].SegmentTemplate.SegmentTimeline.S_asArray;
-                    let endTime = (segments[segments.length - 1].t + segments[segments.length - 1].d) / adaptations[i].SegmentTemplate.timescale * 1000;
-                    manifest.availabilityStartTime = new Date(manifestLoadedTime.getTime() - endTime);
-
                     // Match timeShiftBufferDepth to video segment timeline duration
                     if (manifest.timeShiftBufferDepth > 0 &&
                         manifest.timeShiftBufferDepth !== Infinity &&
@@ -727,6 +722,7 @@ function MssParser(config) {
         // In case of live streams:
         // 1- configure player buffering properties according to target live delay
         // 2- adapt live delay and then buffers length in case timeShiftBufferDepth is too small compared to target live delay (see PlaybackController.computeLiveDelay())
+        // 3- Set retry attempts and intervals for FragmentInfo requests
         if (manifest.type === 'dynamic') {
             let targetLiveDelay = mediaPlayerModel.getLiveDelay();
             if (!targetLiveDelay) {

src/streaming/ManifestLoader.js

@@ -225,6 +225,10 @@ function ManifestLoader(config) {
     function reset() {
         eventBus.off(Events.XLINK_READY, onXlinkReady, instance);
 
+        if (mssHandler) {
+            mssHandler.reset();
+        }
+
         if (xlinkController) {
             xlinkController.reset();
             xlinkController = null;
@@ -234,10 +238,6 @@ function ManifestLoader(config) {
             urlLoader.abort();
             urlLoader = null;
         }
-
-        if (mssHandler) {
-            mssHandler.reset();
-        }
     }
 
     instance = {

src/streaming/controllers/PlaybackController.js

@@ -386,8 +386,8 @@ function PlaybackController() {
         return startTime;
     }
 
-    function getActualPresentationTime(currentTime) {
-        const DVRMetrics = dashMetrics.getCurrentDVRInfo();
+    function getActualPresentationTime(currentTime, mediatype) {
+        const DVRMetrics = dashMetrics.getCurrentDVRInfo(mediatype);
         const DVRWindow = DVRMetrics ? DVRMetrics.range : null;
         let actualTime;
 
@@ -430,12 +430,12 @@ function PlaybackController() {
         wallclockTimeIntervalId = null;
     }
 
-    function updateCurrentTime() {
+    function updateCurrentTime(mediaType) {
         if (isPaused() || !isDynamic || videoModel.getReadyState() === 0) return;
         const currentTime = getNormalizedTime();
-        const actualTime = getActualPresentationTime(currentTime);
+        const actualTime = getActualPresentationTime(currentTime, mediaType);
         const timeChanged = (!isNaN(actualTime) && actualTime !== currentTime);
-        if (timeChanged) {
+        if (timeChanged && !isSeeking()) {
             logger.debug(`UpdateCurrentTime: Seek to actual time: ${actualTime} from currentTime: ${currentTime}`);
             seek(actualTime);
         }
@@ -979,6 +979,7 @@ function PlaybackController() {
         isSeeking: isSeeking,
         getStreamEndTime,
         seek: seek,
+        updateCurrentTime: updateCurrentTime,
         reset: reset
     };
 

src/streaming/net/HTTPLoader.js

@@ -159,6 +159,10 @@ function HTTPLoader(cfg) {
                         internalLoad(config, remainingAttempts);
                     }, mediaPlayerModel.getRetryIntervalsForType(request.type));
                 } else {
+                    if (request.type === HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE) {
+                        return;
+                    }
+
                     errHandler.error(new DashJSError(downloadErrorToRequestTypeMap[request.type], request.url + ' is not available', {
                         request: request,
                         response: httpRequest.response
@@ -355,6 +359,11 @@ function HTTPLoader(cfg) {
         delayedRequests = [];
 
         requests.forEach(x => {
+            // MSS patch: ignore FragmentInfo requests
+            if (x.request.type === HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE) {
+                return;
+            }
+
             // abort will trigger onloadend which we don't want
             // when deliberately aborting inflight requests -
             // set them to undefined so they are not called

src/streaming/vo/metrics/HTTPRequest.js

@@ -166,6 +166,7 @@ HTTPRequest.INIT_SEGMENT_TYPE = 'InitializationSegment';
 HTTPRequest.INDEX_SEGMENT_TYPE = 'IndexSegment';
 HTTPRequest.MEDIA_SEGMENT_TYPE = 'MediaSegment';
 HTTPRequest.BITSTREAM_SWITCHING_SEGMENT_TYPE = 'BitstreamSwitchingSegment';
+HTTPRequest.MSS_FRAGMENT_INFO_SEGMENT_TYPE = 'FragmentInfoSegment';
 HTTPRequest.LICENSE = 'license';
 HTTPRequest.OTHER_TYPE = 'other';