From: Georgi Chorbadzhiyski <gf@unixsol.org>
To: linux-media@vger.kernel.org
Subject: How to set pixelaspect in struct v4l2_cropcap returned by VIDIOC_CROPCAP?
Date: Sun, 16 Sep 2012 18:32:52 +0300 [thread overview]
Message-ID: <5055F124.8020507@unixsol.org> (raw)
Guys I'm adding v4l2 output device support for VLC/ffmpeg/libav (I'm using
v4l2loopback [1] driver for testing) but I have a problem which I can't seem
to find a solution.
VLC [2] uses VIDIOC_CROPCAP [3] to detect the pixelaspect ratio of the input
it receives from v4l2 device. But I can't seem to find a way to set struct
v4l2_cropcap.pixelaspect when I'm outputting data to the device and the
result is that VLC assumes pixelaspect is 1:1.
I was hoping that VIDIOC_S_CROP [4] would allow setting pixelaspect but
according to docs that is not case. What am I missing?
How to set pixelaspect values returned by VIDIOC_CROPCAP?
[1]: https://github.com/umlaeute/v4l2loopback
[2]: http://git.videolan.org/?p=vlc.git;a=blob;f=modules/access/v4l2/demux.c;hb=HEAD#l248
[3]: http://www.linuxtv.org/downloads/v4l-dvb-apis/vidioc-cropcap.html
[4]: http://www.kernel.org/doc/htmldocs/media/vidioc-g-crop.html
--
Georgi Chorbadzhiyski
http://georgi.unixsol.org/
next reply other threads:[~2012-09-16 15:32 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-16 15:32 Georgi Chorbadzhiyski [this message]
2012-09-16 16:28 ` How to set pixelaspect in struct v4l2_cropcap returned by VIDIOC_CROPCAP? Hans Verkuil
2012-09-16 16:49 ` Georgi Chorbadzhiyski
[not found] ` <201209171022.52930.hverkuil@xs4all.nl>
2012-09-17 9:07 ` Georgi Chorbadzhiyski
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