[MEncoder-users] Some small feature requests for mencoder

[Fabian Giesen]

Hi,

first a short overview of the problem I'm having: I'm one of the primary 
organizers of breakpoint (http://breakpoint.untergrund.net), an annual 
demoscene party (real-time art festival if you want :) in Germany. We 
have several demo competitions and have gotten entries running on 
basically anything that executes code over the years. There's no way to 
collect a lot of these devices to a video projector, and besides it 
would be a major hassle to reconnect everything again and again during a 
competition, so we make videos where we can (usually DV for anything we 
capture ourselves).

We also have seminars, liveacts and other events, which are also taped; 
so in the end we end up with lots of raw DV material (around 1.5TB last 
year) that have to be encoded. We did this manually last year (a major 
pain, I don't think I have to explain further) and plan to do it 
semi-automatically this year, with a small encoding farm together with a 
short python app that distributes encoding jobs to machines on that farm.

This is where mencoder enters the scene. We have a lot of captures from 
machines like C64s and Amigas that tend to do things like 1pixel/frame 
scrollers. mencoder with yadif/mcdeint gives *by far* the best results 
among everything we've tested on those captures, so we want to use it, 
BUT: (and here's the actual problem, sorry for the long intro ;)

It seems that yadif needs to buffer about 3 frames before it can start 
working (not surprising given the way it works). During that time, it 
simply seems to return junk frames with a timestamp of 0 (or whatever). 
No problem in mplayer, but in mencoder, it means that there's a few too 
many frames, which is not only annoying (each encoded video starts with 
3 green frames), it also means there are too many frames in the data 
stream, so mencoder later drops 3 frames to get back in sync again.

In short, it would be really great if there's a way to work around that, 
but I haven't been able to figure out how to do so (even after intensive 
lecture of the man page ;), and it would be great if someone has a solution.

Thanks in advance!

-Fabian "ryg/farbrausch" Giesen
  Breakpoint organizing team