[MPlayer-dev-eng] [PATCH] muxer_lavf: fix compilation with newer FFmpeg.

[Reimar Döffinger]

> On 2 May 2021, at 23:48, Alexander Strasser <eclipse7 at gmx.net> wrote:
> 
> Hi all,
> 
> I tested this patch a little and it seems to be fine.
> 
> I noticed one difference in output files I can't explain; though
> somehow the new output seems to be more correct than the old one.
> 
> If you check the output of
> 
>    mencoder "$FATE_SAMPLES"/msmpeg4v1/mpg4.avi -ovc copy -of lavf -o mpeg4-muxer_lavf.avi
> 
> MPlayer says (version without patch vs version with patch)
> 
>    VIDEO:  [MPG4]  352x240  24bpp  600.000 fps  1513.3 kbps (184.7 kbyte/s)
>    VIDEO:  [MPG4]  352x240  24bpp  29.970 fps  1484.6 kbps (181.2 kbyte/s)
> 

That is expected, the code before set the codec time base, which if it ever
was used, at least was not used recently by FFmpeg.
It now sets the stream time base, which works.
There is a risk (I did not investigate) that it breaks some variable frame rate
content, however I think mencoder can’t handle that anyway.