feat: Implement live to live switch back

samples/alternative/index.html

@@ -35,7 +35,6 @@
             video = document.getElementById('video-element');
             alternativeVideo = document.getElementById('alternative-video-element');
             player = dashjs.MediaPlayer().create();
-            alternativeVideo = document.querySelector('#alternativeVideo');
             player.initialize(video, url, false);
             player.setAlternativeVideoElement(alternativeVideo);
         }

src/streaming/MediaManager.js

@@ -40,7 +40,6 @@ function MediaManager() {
         isSwitching = false,
         hideAlternativePlayerControls = false,
         altPlayer,
-        fullscreenDiv,
         playbackController,
         altVideoElement,
         alternativeContext,
@@ -84,17 +83,6 @@ function MediaManager() {
 
         logger = debug.getLogger(instance);
 
-        if (!fullscreenDiv) {
-            fullscreenDiv = document.createElement('div');
-            fullscreenDiv.id = 'fullscreenDiv';
-            const videoElement = videoModel.getElement();
-            const parentNode = videoElement && videoElement.parentNode;
-            if (parentNode) {
-                parentNode.insertBefore(fullscreenDiv, videoElement);
-                fullscreenDiv.appendChild(videoElement);
-            }
-        }
-
         document.addEventListener('fullscreenchange', () => {
             if (document.fullscreenElement === videoModel.getElement()) {
                 // TODO: Implement fullscreen
@@ -117,7 +105,9 @@ function MediaManager() {
             const prebufferedPlayer = MediaPlayer().create();
             prebufferedPlayer.initialize(null, alternativeMpdUrl, false, NaN);
             prebufferedPlayer.updateSettings({
-                streaming: {cacheInitSegments: true}
+                streaming: {
+                    cacheInitSegments: true
+                }
             });
             prebufferedPlayer.preload();
             prebufferedPlayer.setAutoPlay(false);
@@ -162,7 +152,6 @@ function MediaManager() {
         if (altPlayer) {
             altPlayer.off(Events.ERROR, onAlternativePlayerError, this);
         }
-
         altPlayer = MediaPlayer().create();
         altPlayer.updateSettings({
             streaming: {
@@ -201,14 +190,13 @@ function MediaManager() {
         }
 
         if (altPlayer && altVideoElement) {
+            altVideoElement.style.display = 'block';
             altPlayer.attachView(altVideoElement);
         }
 
         videoModel.pause();
-        logger.debug('Main video paused');
-
         videoModel.getElement().style.display = 'none';
-        altVideoElement.style.display = 'block';
+        logger.debug('Main video paused');
 
         if (time) {
             logger.debug(`Seeking alternative content to time: ${time}`);
@@ -242,7 +230,12 @@ function MediaManager() {
 
         if (playbackController.getIsDynamic()) {
             logger.debug('Seeking to original live point for dynamic manifest');
-            playbackController.seekToOriginalLive(true, false, false);
+            if (seekTime > playbackController.getDvrWindowStart()) {
+                playbackController.seek(seekTime, false, false);
+            } else {
+                logger.warn('Seek time is before DVR window start, seeking to start of DVR window');
+                playbackController.seekToDvrWindowStart();
+            }   
         } else {
             logger.debug(`Seeking main content to time: ${seekTime}`);
             playbackController.seek(seekTime, false, false);

src/streaming/controllers/AlternativeMediaController.js

@@ -41,25 +41,6 @@ function AlternativeMediaController() {
     const context = this.context;
     const eventBus = EventBus(context).getInstance();
 
-    function _calculateSeekTime(currentEvent, altPlayer) {
-        let seekTime;
-        if (currentEvent.mode === Constants.ALTERNATIVE_MPD.MODES.REPLACE) {
-            if (currentEvent.returnOffset || currentEvent.returnOffset === 0) {
-                seekTime = currentEvent.presentationTime + currentEvent.returnOffset;
-                logger.debug(`Using return offset - seeking to: ${seekTime}`);
-            } else {
-                const alternativeDuration = altPlayer.duration()
-                const alternativeEffectiveDuration = !isNaN(currentEvent.maxDuration) ? Math.min(currentEvent.maxDuration, alternativeDuration) : alternativeDuration
-                seekTime = currentEvent.presentationTime + alternativeEffectiveDuration;
-                logger.debug(`Using alternative duration - seeking to: ${seekTime}`);
-            }
-        } else if (currentEvent.mode === Constants.ALTERNATIVE_MPD.MODES.INSERT) {
-            seekTime = currentEvent.presentationTime;
-            logger.debug(`Insert mode - seeking to original presentation time: ${seekTime}`);
-        }
-        return seekTime;
-    }
-
     let instance,
         debug,
         logger,
@@ -314,6 +295,25 @@ function AlternativeMediaController() {
         }
     }
 
+    function _calculateSeekTime(currentEvent, altPlayer) {
+        let seekTime;
+        if (currentEvent.mode === Constants.ALTERNATIVE_MPD.MODES.REPLACE) {
+            if (currentEvent.returnOffset || currentEvent.returnOffset === 0) {
+                seekTime = currentEvent.presentationTime + currentEvent.returnOffset;
+                logger.debug(`Using return offset - seeking to: ${seekTime}`);
+            } else {
+                const alternativeDuration = altPlayer.duration()
+                const alternativeEffectiveDuration = !isNaN(currentEvent.maxDuration) ? Math.min(currentEvent.maxDuration, alternativeDuration) : alternativeDuration
+                seekTime = currentEvent.presentationTime + alternativeEffectiveDuration;
+                logger.debug(`Using alternative duration - seeking to: ${seekTime}`);
+            }
+        } else if (currentEvent.mode === Constants.ALTERNATIVE_MPD.MODES.INSERT) {
+            seekTime = currentEvent.presentationTime;
+            logger.debug(`Insert mode - seeking to original presentation time: ${seekTime}`);
+        }
+        return seekTime;
+    }
+
     function _resetAlternativeSwitchStates() {
         currentEvent = null;
         actualEventPresentationTime = 0;

src/streaming/controllers/EventController.js

@@ -502,6 +502,29 @@ function EventController() {
         }
     }
 
+    /**
+     * Auxiliary method to check for earliest resolution time events and return alternative MPD
+     * @param {object} event
+     * @return {object|null} - Returns the alternative MPD if it exists and has earliestResolutionTimeOffset, null otherwise
+     * @private
+     */
+    function _checkForEarliestResolutionTimeEvents(event) {
+        try {
+            if (!event || !event.alternativeMpd) {
+                return null;
+            }
+
+            if (event.alternativeMpd.earliestResolutionTimeOffset !== undefined) {
+                return event.alternativeMpd;
+            }
+
+            return null;
+        } catch (e) {
+            logger.error(e);
+            return null;
+        }
+    }
+
     /**
      * Checks if the event has an earliestResolutionTimeOffset and if it's ready to resolve
      * @param {object} event
@@ -511,11 +534,13 @@ function EventController() {
      */
     function _checkEventReadyToResolve(event, currentVideoTime) {
         try {
-            if (!event.alternativeMpd.earliestResolutionTimeOffset || event.triggeredReadyToResolve) {
+            const earlyToResolveEvent = _checkForEarliestResolutionTimeEvents(event);
+
+            if (!earlyToResolveEvent || event.triggeredReadyToResolve) {
                 return false;
             }
 
-            const resolutionTime = event.calculatedPresentationTime - event.alternativeMpd .earliestResolutionTimeOffset;
+            const resolutionTime = event.calculatedPresentationTime - earlyToResolveEvent.earliestResolutionTimeOffset;
             return currentVideoTime >= resolutionTime;
         } catch (e) {
             logger.error(e);

src/streaming/controllers/PlaybackController.js

@@ -267,6 +267,25 @@ function PlaybackController() {
         seek(seektime, stickToBuffered, internal, adjustLiveDelay);
     }
 
+    function seekToStartDvrWindow(stickToBuffered = false, internal = false, adjustLiveDelay = false) {
+        const dvrWindowStart = getDvrWindowStart();
+
+        if (dvrWindowStart === 0) {
+            return;
+        }
+
+        seek(dvrWindowStart, stickToBuffered, internal, adjustLiveDelay);
+    }
+
+    function getDvrWindowStart() {
+        if (!streamInfo || !videoModel || !isDynamic) {
+            return;
+        }
+        const type = streamController && streamController.hasVideoTrack() ? Constants.VIDEO : Constants.AUDIO;
+        const dvrInfo = dashMetrics.getCurrentDVRInfo(type);
+        return dvrInfo && dvrInfo.range ? dvrInfo.range.start : 0;
+    }
+
     function _getDvrWindowEnd() {
         if (!streamInfo || !videoModel || !isDynamic) {
             return;
@@ -922,6 +941,7 @@ function PlaybackController() {
         getAvailabilityStartTime,
         getBufferLevel,
         getCurrentLiveLatency,
+        getDvrWindowStart,
         getEnded,
         getInitialCatchupModeActivated,
         getIsDynamic,
@@ -947,6 +967,7 @@ function PlaybackController() {
         seek,
         seekToCurrentLive,
         seekToOriginalLive,
+        seekToStartDvrWindow,
         setConfig,
         updateCurrentTime,
     };