Re: [RFC] v4l2 support for thermopile devices

From: Attila Kinali
Date: Thu Nov 03 2016 - 09:30:48 EST


On Wed, 2 Nov 2016 23:10:41 -0700
Matt Ranostay <matt@xxxxxxxxxxxxxxxxxxx> wrote:

>
> So does anyone know of any software that is using V4L2_PIX_FMT_Y12
> currently? Want to test my driver but seems there isn't anything that
> uses that format (ffmpeg, mplayer, etc).
>
> Raw data seems correct but would like to visualize it :). Suspect I'll
> need to write a test case application though

I was pretty sure that MPlayer supports 12bit greyscale, but I cannot
find where it was handled. You can of course pass it to the MPlayer
internas as 8bit greyscale, which would be IMGFMT_Y8 or just pass
it on as 16bit which would be IMGFMT_Y16_LE (LE = little endian).

You can find the internal #defines of the image formats in
libmpcodecs/img_format.h and can use https://www.fourcc.org/yuv.php
to decode their meaning.

The equivalent for libav would be libavutil/pixfmt.h

Luca Barbato tells me that adding Y12 support to libav would be easy.

Attila Kinali

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