[Libav-user] Recent ffmpeg version doesn't support v4l2

Stefano Sabatini stefano.sabatini-lala at poste.it
Sat Jul 2 12:47:48 CEST 2011

On date Friday 2011-07-01 15:23:58 -0300, Leandro Santiago encoded:
> Sorry for the delay (I was busy these days and couldn't answer). I
> continue having problems with ffmpeg from trunk. The last which worked
> with me is 0.7rc
> the pastebin is in:
> http://pastebin.com/rLL2jBUp
> and the error, when I call av_open_input_file is:
> [video4linux2 @ 0xa904180] ioctl set time per frame(7/8560628) failed

Whence does this 7/8560628 value comes from?
> this call returns a valid value, but so I can't find any streams in
> the input. With 0.7rc everything works fine.

The problem is related to this hunk:

    oFormatParams.standard = "ntsc";
    pIFormat = av_find_input_format("video4linux2");
    bRet = av_open_input_file(&pIFormatCtx, sFile, pIFormat, 0, &oFormatParams);

Note that av_open_input_file() was recently deprecated, maybe something
went wrong in the transition with the new API.

I suggest you to try with latest git, and check if it works with
ffmpeg/ffplay (debugging with gdb will show you why this is happening).

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