[FFmpeg-devel] Request for assistance with adding new pixel format (NV12_8L128) in FFmpeg

[Devin Heitmueller]

On Wed, Feb 8, 2023 at 8:08 AM Jean-Baptiste Kempf <jb at videolan.org> wrote:
> Do we really need those PIX_FMT in FFmpeg public API?

Tiled formats are annoying, but not uncommon in popular embedded
platforms (e.g. NXP iMX, TI Davinci).  Of course ffmpeg could choose
to ignore them, but it would effectively prevent it from being used on
those platforms (and it's pretty essential to use the hardware blocks
to do any real video processing).

In the past there was an expectation that adding new pixel formats
required the contributor to also add corresponding routines to swscale
to convert to more common formats that ffmpeg works with.  You could
alternatively treat it as a packet format and require a decoder to do
the conversion to something more common to ffmpeg, but this would both
be expensive (in terms of CPU usage and memory copying) and
effectively prevent you from being able to capture or decode in the
native format and then hand off those buffers to other hardware blocks
like encoders, colorspace conversion, etc.

Devin

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Devin Heitmueller, Senior Software Engineer
LTN Global Communications
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