stream-controller: isolate start position adjustement logic

ensure that media.currentTime is adjusted to expected start position as soon as possible related to https://github.com/dailymotion/hls.js/issues/499
normenster · Jun 14, 2016 · 203dc09 · 203dc09
1 parent 568bbb7
commit 203dc09
Showing 1 changed file with 26 additions and 38 deletions.
diff --git a/src/controller/stream-controller.js b/src/controller/stream-controller.js
@@ -1067,29 +1067,32 @@ class StreamController extends EventHandler {
 
 _checkBuffer() {
     var media = this.media;
-    if(media) {
-      // compare readyState
-      let readyState = media.readyState;
-      // if ready state different from HAVE_NOTHING (numeric value 0), we are allowed to seek
-      if(readyState) {
-        let targetSeekPosition,
-            currentTime = media.currentTime,
-            loadedmetadata = this.loadedmetadata;
-
-        // adjust currentTime to start position on loaded metadata
-        if(!loadedmetadata && media.buffered.length) {
-          this.loadedmetadata = true;
-          // only adjust currentTime if not equal to 0
-          if (!currentTime && currentTime !== this.startPosition) {
-            targetSeekPosition = this.startPosition;
+    // if ready state different from HAVE_NOTHING (numeric value 0), we are allowed to seek
+    if(media && media.readyState) {
+        let currentTime = media.currentTime;
+      // adjust currentTime to start position on loaded metadata
+      if(!this.loadedmetadata && media.buffered.length) {
+        this.loadedmetadata = true;
+        // only adjust currentTime if startPosition not equal to 0
+        let startPosition = this.startPosition;
+        if (!currentTime && currentTime !== startPosition) {
+          if (startPosition) {
+            logger.log(`target start position:${startPosition}`);
+            let bufInfo = BufferHelper.bufferInfo(media,startPosition,0);
+            if(bufInfo.len === 0) {
+              let nextStart = bufInfo.nextStart;
+              if (nextStart !== undefined &&
+                 (nextStart - startPosition) < this.config.maxSeekHole) {
+                startPosition = nextStart;
+                logger.log(`target start position not buffered, seek to next buffered ${startPosition}`);
+              }
+            }
+            logger.log(`adjust currentTime from ${currentTime} to ${startPosition}`);
+            media.currentTime = startPosition;
           }
         }
-
-        if (targetSeekPosition) {
-          currentTime = targetSeekPosition;
-          logger.log(`target seek position:${targetSeekPosition}`);
-        }
-        var bufferInfo = BufferHelper.bufferInfo(media,currentTime,0),
+      } else {
+        let bufferInfo = BufferHelper.bufferInfo(media,currentTime,0),
             expectedPlaying = !(media.paused || // not playing when media is paused
                                 media.ended  || // not playing when media is ended
                                 media.buffered.length === 0), // not playing if nothing buffered
@@ -1101,8 +1104,7 @@ _checkBuffer() {
           logger.log(`playback not stuck anymore @${currentTime}`);
         }
         // check buffer upfront
-        // if less than jumpThreshold second is buffered, and media is expected to play but playhead is not moving,
-        // and we have a new buffer range available upfront, let's seek to that one
+        // if less than jumpThreshold second is buffered, let's check in more details
         if(expectedPlaying && bufferInfo.len <= jumpThreshold) {
           if(playheadMoving) {
             // playhead moving
@@ -1119,7 +1121,7 @@ _checkBuffer() {
               this.seekHoleNudgeDuration += this.config.seekHoleNudgeDuration;
             }
           }
-          // if we are below threshold, try to jump if next buffer range is close
+          // if we are below threshold, try to jump to start of next buffer range if close
           if(bufferInfo.len <= jumpThreshold) {
             // no buffer available @ currentTime, check if next buffer is close (within a config.maxSeekHole second range)
             var nextBufferStart = bufferInfo.nextStart, delta = nextBufferStart-currentTime;
@@ -1134,20 +1136,6 @@ _checkBuffer() {
               this.hls.trigger(Event.ERROR, {type: ErrorTypes.MEDIA_ERROR, details: ErrorDetails.BUFFER_SEEK_OVER_HOLE, fatal: false, hole : hole});
             }
           }
-        } else {
-          let currentTime = media.currentTime;
-          if (targetSeekPosition && currentTime !== targetSeekPosition) {
-            if(bufferInfo.len === 0) {
-              let nextStart = bufferInfo.nextStart;
-              if (nextStart !== undefined &&
-                 (nextStart - targetSeekPosition) < this.config.maxSeekHole) {
-                targetSeekPosition = nextStart;
-                logger.log(`target seek position not buffered, seek to next buffered ${targetSeekPosition}`);
-              }
-            }
-            logger.log(`adjust currentTime from ${currentTime} to ${targetSeekPosition}`);
-            media.currentTime = targetSeekPosition;
-          }
         }
       }
     }