[Ffmpeg-devel] new grab interface breaks bktr grabing

Nikns Siankin nikns
Mon Apr 2 10:59:02 CEST 2007

First I tried:
ffmpeg -y -f bktr -i /dev/bktr0 -an -vcodec wmv2 -tvstd pal /root/test.wmv
/dev/bktr0: Error while opening file

Then I remembered that even with old ffmpeg there was such error if no frame
size specified, but running:
ffmpeg -y -f bktr -i /dev/bktr0 -an -vcodec wmv2 -tvstd pal -s cif /root/test.wmv
didn't help either.

Hovewer, specifying "-s" in front of args finnaly started capturing:
ffmpeg -y -s cif -f bktr -i /dev/bktr0 -an -vcodec wmv2 -tvstd pal /root/test.wmv
Input #0, bktr, from '/dev/bktr0':
  Duration: N/A, bitrate: N/A
  Stream #0.0: Video: rawvideo, yuv420p, 352x288, 25.00 fps(r)
Output #0, asf, to '/root/test.wmv':
  Stream #0.0: Video: wmv2, yuv420p, 352x288, q=2-31, 200 kb/s, 25.00 fps(c)
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding

but grabing status isn't shown and 'ffplay test.wmv' showed only one frame.

I guess that, removed prepare_grab() from ffmpeg.c did some magic that
made bktr video grabbing work.
Anyway - would be good idea to set default frame size for bktr,
so that it would work wihout specifying "-s" and/or example in
manpage would be very usefull too.

Anyone have success grabing from bktr with new grab interface?

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