[FFmpeg-user] overlays, setdar error

[Stefano Sabatini]

On date Wednesday 2011-03-30 17:06:59 +0000, Mark Robinson encoded:
> Alastair Mason <alabandit <at> gmail.com> writes:
[...]
> The offending line is in ffmpeg.c I think, at least that sneakily adds setdar on 
> the end of your filter chain. At a guess setdar API has changed since this was 
> done?
> 
> #if CONFIG_AVFILTER
>         if(frame_aspect_ratio > 0){
>             i = vfilters ? strlen(vfilters) : 0;
>             vfilters = av_realloc(vfilters, i+100);
>             snprintf(vfilters+i, i+100, "%csetdar=%f\n", i?',':' ', 
> frame_aspect_ratio);
>             frame_aspect_ratio=0;
>         }
> 
>         ost->avfilter= vfilters;
>         vfilters= NULL;
> #endif

Yes the code is brittle, in this case we had: "...[out], setdar=N:M",
which is not valid syntax, we need to fix the code.
-- 
ffmpeg-user random tip #3
Some few multimedia formats (mpeg-1, mpeg-2:PS, DV) support physical merge 
consistency, which means you can merge two files with cat. E.g.:
cat input1.mpeg input2.mpeg > output.mpeg
See: http://www.ffmpeg.org/faq.html#SEC25