[FFmpeg-devel] libavformat and video4linux2 acquire problems

Limin Wang lance.lmwang
Wed May 9 04:30:51 CEST 2007


> > I had the exact same problem last week. The v4l2 driver resetted the
> > card from 720x576 to 640x576, while it used to work OK until at least
> > april this year.
> [...]
> On March 29 I committed a patch that allows to set the tv standard. By 
> default, ffmpeg sets the ntsc standard, unless you specify a different 
> tv standard by using the "-tvstd " option. Can you try "-tvstd pal" to 
> see if it fixes your problem? If not, can you try commenting out the
>      if( v4l2_set_parameters( s1, ap ) < 0 )
>          return AVERROR_IO;
> lines in v4l2_read_header()?

Yes, you need set the tv standard(-tvstd [PAL,NTSC, PAL-I,..]) and tv input(-vc
[0-max]) in svn. Both PAL and NTSC are no problem by my test. In my local
copy, I have changed default tvstd to NULL. and -vc to string(S-video,
composite0,...) and haven't submit. If needed, I can submit for review.


More information about the ffmpeg-devel mailing list