[MEncoder-users] forcing encode of lost frames as duplicates

[Corey Hickey]

Josh Sutton wrote:
> Hi,
> 
> I'm trying to produce a video from a video server stream running 
> across a lossy wireless link.  The problem is that time needs to 
> be preserved even if frames are lost.  ie if I'm receiving nominally 
> 30 fps and say 20 frames are lost, then the remaining 10 frames should
>  be duplicated such that they still occupy 1 second. 
>  
> The duplicate frames work fine using mplayer and displaying on the screen.
> If I start mplayer displaying on the screen and disconnect the ethernet to 
> simulate frame losses, then mplayer holds the last frame.  However when I use 
> mencoder to either copy or reencode the stream to disk, the missing frames 
> are skipped (not inserted), and the playback shows time discontinuities.
> 
> I've also tried using mplayer with the -vo jpeg option.  But skipped frames are
> not encoded.
> 
> the mencoder.exe harddup switch does not work.

You mean '-vf harddup', right?

> I suspect because the frames are
> missing, not duplicates.

What exactly is the video data you're feeding mencoder? Is it an MPEG,
or a series of JPEGs, or what?

Please post your full mencoder command line and the _entire_ output of
mencoder for a representative session. Without ever having done a
project like what you're doing, I could only speculate until I have more
information.

-Corey