[MPlayer-users] audio half-speed in mencoder v4l TV recording

Mike Holland myk at plug.linux.org.au
Thu Nov 28 08:23:02 CET 2002


Folks,
 I am recording from a BT878 TV card, and find the audio at
half-speed on playback, with corresponding drop in pitch and volume. Its
the same when playing back under assorted windoze players. If I play back
with 'mplayer -speed 2', the audio sounds OK, but video doesnt speed up
much. They soon get out of sync.
   Video is fine. I'm very impressed to see full-res PAL in real-time.

  I'm new here and not sure what to try next. Have browsed the last couple 
of months of this list from the archives, read the docs, tried the source 
(almost no comments). Is a video driver problem likely in this case?
   I tried to get btaudio working, but no sucess yet.

Hardware: nvidia nForce motherboard with i810_audio ; PixelView PlayTV 
pro. ; Duron 1.2 ; 256MB DDR; fast hdd.
Software: RedHat 7.3, linux 2.4.18, mplayer-0.90pre10

% mencoder -v  -tv 
on:driver=v4l:width=768:height=576:device=/dev/video0:input=1 -o tv.avi \
    -ovc lavc  -vop pp=lb -oac mp3lame

Output includes:
  Opening audio decoder: [pcm] Uncompressed PCM audio decoder
  AUDIO: 44100 Hz, 1 ch, 16 bit (0x10), ratio: 88200->88200 (705.6 kbit)
  Selected audio codec: [pcm] afm:pcm (Uncompressed PCM)
  MP3 audio selected
  Building audio filter chain for 44100Hz/1ch/16bit -> 
44100Hz/1ch/16bit...
  Forcing audio preload to 0, max pts correction to 0
  Pos:   6.0s     92f ( 0%)  23fps Trem:   0min   0mb  A-V:0.000 
[818:110]]

See verbose log at http://www.golden.wattle.id.au/mencoder-log.txt

Same result with 'copy' or 'pcm' audio coding. No problems recording 
audio with sox.
   I hope I havnt missed anything too obvious.

regards, Mike.

-- 
        The origin of Truth is Doubt - Socrates




More information about the MPlayer-users mailing list