Changeset 288413 in webkit

Timestamp:

Jan 22, 2022, 7:38:09 PM (5 years ago)

Author:

Peng Liu

Message:

REGRESSION (Safari 15?): Blob videos slow to pause, affects CBS and CNN
​https://bugs.webkit.org/show_bug.cgi?id=234066

Reviewed by Jer Noble.

MediaPlayerPrivateMediaSourceAVFObjC::playInternal() calls [m_synchronizer setRate:],
which will make the return value of MediaPlayerPrivateMediaSourceAVFObjC::paused() change
from true to false. But it won't push the new paused value back to the Web process.

RemoteMediaPlayerProxy::play() does call sendCachedState() after calling
m_player->play(), but because MediaPlayerPrivateMediaSourceAVFObjC::playInternal() is not
called in the same run loop, sendCachedState() won't send back the updated paused value either.

In most cases, this is not an issue, because other member functions of RemoteMediaPlayerProxy
will call sendCachedState() to push the updated paused value back to the Web process later.
However, we did find some videos need the paused value to be pushed back the Web process
in a timely manner.

No new tests, manually tested.

• platform/graphics/avfoundation/objc/MediaPlayerPrivateMediaSourceAVFObjC.mm:

(WebCore::MediaPlayerPrivateMediaSourceAVFObjC::playInternal):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/avfoundation/objc/MediaPlayerPrivateMediaSourceAVFObjC.mm (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2022-01-22  Peng Liu  <peng.liu6@apple.com>
+
+        REGRESSION (Safari 15?): Blob videos slow to pause, affects CBS and CNN
+        https://bugs.webkit.org/show_bug.cgi?id=234066
+
+        Reviewed by Jer Noble.
+
+        `MediaPlayerPrivateMediaSourceAVFObjC::playInternal()` calls `[m_synchronizer setRate:]`,
+        which will make the return value of `MediaPlayerPrivateMediaSourceAVFObjC::paused()` change
+        from true to false. But it won't push the new `paused` value back to the Web process.
+
+        `RemoteMediaPlayerProxy::play()` does call `sendCachedState()` after calling
+        `m_player->play()`, but because `MediaPlayerPrivateMediaSourceAVFObjC::playInternal()` is not
+        called in the same run loop, `sendCachedState()` won't send back the updated `paused` value either.
+
+        In most cases, this is not an issue, because other member functions of `RemoteMediaPlayerProxy`
+        will call `sendCachedState()` to push the updated `paused` value back to the Web process later.
+        However, we did find some videos need the `paused` value to be pushed back the Web process
+        in a timely manner.
+
+        No new tests, manually tested.
+
+        * platform/graphics/avfoundation/objc/MediaPlayerPrivateMediaSourceAVFObjC.mm:
+        (WebCore::MediaPlayerPrivateMediaSourceAVFObjC::playInternal):
+
 2022-01-22  Said Abou-Hallawa  <said@apple.com>
 

trunk/Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateMediaSourceAVFObjC.mm

@@ -351 +351 @@
     [m_synchronizer setRate:m_rate];
 #endif
+
+    m_player->playbackStateChanged();
 }
 
@@ -381 +383 @@
     [m_synchronizer setRate:0];
 #endif
+
+    m_player->playbackStateChanged();
 }