[mythtv] Re: codec that deals best with badly synced video

[John Coiner]

 >From a discussion on the mjpeg list it was mentioned that vcr's
 >typically have horrible video sync which will usually give encoders a
 >fit, resulting in high cpu usage and/or a/v sync problems or dropouts.
...
 >The problem I experience is that every 20-30 seconds or so I get an
 >audio dropout and a video hiccup and then a second or two later the 2 
 >get in sync again.

 >This only seems to happen when watching with a vcr input.

I would not expect the codec to make a difference. The code which talks 
to the video capture device is independent of which codec you use. 
Likewise the a/v sync code is pretty much independent of the encoder.

If the VCR sends a lousy signal, or periodically drops a frame, that 
will manifest itself to mythtv as dropped frames which (don't) show up 
at the 'v4l' interface.

We have code that is supposed to detect when the v4l capture device has 
dropped a frame, and and we have code that is supposed to deal with this 
gracefully. It sounds like there could be a bug in this code.

I am going to hook up a VCR and try to reproduce this problem, and debug 
further....

- john