mplayer: reset audio/video delay if there's no next video frame

mpctx->delay is used to control audio/video sync. If more audio than
video has been played, it grows larger, meaning A/V desync is happening.

This logic is a bit broken when video has ended, and audio is still
playing. In that case, it tries to read additional video frames from the
video decoder (because even if you don't feed new packets to the
decoder, it could still return delayed frames). For that, the code to
determine whether frames should be dropped is invoked
(check_framedrop()). This function detects that video is behind audio (mpctx-
>delay growing big),
and attempts to issue a framedrop.

Reset mpctx->delay if there's no more video.

This fixes the the frame drop display "counting up" on each playloop
iteration when playing audio files with cover art. These files are
basically audio+video files with a single video frame. When playing
these files the the corner case of having run out of video while audio
is still playing is the normal case.

Also reset mpctx->last_av_difference. This is not updated anymore if
video ends (since update_avsync() sets it, but it's not called if
video_left is false). This removes the "stuck" A/V sync value when video
ends. With audio files containing cover art we would display a
meaningless value over the duration of the whole file otherwise.

1 files changed, 4 insertions, 0 deletions

diff --git a/core/mplayer.c b/core/mplayer.c
index a7761b4da5..6d0405620b 100644
--- a/core/mplayer.c
+++ b/core/mplayer.c
@@ -3264,6 +3264,10 @@ static void run_playloop(struct MPContext *mpctx)
                 mpctx->time_frame += frame_time / opts->playback_speed;
                 adjust_sync(mpctx, frame_time);
             }
+            if (!video_left) {
+                mpctx->delay = 0;
+                mpctx->last_av_difference = 0;
+            }
         }
 
         if (endpts != MP_NOPTS_VALUE)