[MPlayer-users] per-frame seeking in AVI files

[Lars Damerow]

On Wed, 6 Feb 2002, Arpi wrote:

| > I see--clever!. So, a related question: would it be at all feasible for MPlayer
| > to enable forwards and backwards playback if keyframes are detected at every
| > frame, or just if playing back an MJPEG movie? Without synced sound, of course.
|
| yes. it's already on our too long TODO list. near to its end...

I know that feeling. :)

| audio buffering is made at 3 places: demuxer, codec and soundcard.
| we cannot control soundcard, cannot seek backward in demuxer and depending
| on audio format, maybe we cannot control buffering of codec.
| so it's near to impossible.
|
| for short term backward seek, we could perserve last N seconds of decoded
| audio, keep resetting audio device and with some luck and well working audio
| driver it may work...  anyway i don't know what is 40ms audio chunk playback
| good for. you'll hear only ticks, no sound...

For us, silent frame-stepping would be perfect. Single frame stepping really
only make sense when the movie is paused, anyway.

So how about this: if frame-stepping is only enabled when the sound is paused,
the hack you described earlier would work just fine for our purposes, and once
your TODO list is shortened, would work for backward steps as well. Then, once
the movie is unpaused, MPlayer could seek the audio to the right place in the
same way it would when the user had done a 10-second or 10-minute seek. Would
that take care of the A-V syncing issues?

Thanks for your patience with my inquiries; I've been desperate to find a video
player that suits our needs, and MPlayer's playback has really impressed me.
I'm just hoping we can get the usability tweaks that'll make it our player of
choice.

cheers,
lars

___________________________________________________________
lars damerow
button pusher
lars at pixar.com

"We want you to put a monkey in there."