[FFmpeg-devel] [PATCH 2/2] libavcodec/cuviddec: adding HEVC YUV444P decoding support

[Philip Langdale]

On Wed, 13 Feb 2019 19:47:27 +0100
Timo Rothenpieler <timo at rothenpieler.org> wrote:

> On 13.02.2019 09:56, Roman Arzumanyan wrote:
> > Hello,
> > 
> > Please find attached patch, it adds HEVC YUV444P decoding support.
> > 
> > Supported formats are AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV444P10LE, 
> > AV_PIX_FMT_YUV444P12LE.
> > 
> > This feature requires Video Codec SDK 9.  
> 
> There is one big issue with this.
> And that is, that ffmpeg expects the data for YUV444P10 and YUV444P12
> to be in the least significant bits.
> Nvenc (and I hope/assume as does nvdec/cuvid) on the other hand put
> the data into the most significant bits.
> 
> As a workaround we have so far resorted to using the 16 bit pix_fmt 
> everywhere, as it happens to match up.
> That has the issue of losing the information about the bit depth.
> So far every attempt at solving it (like, adding new pix_fmts that
> match what nvenc/dec uses) have not found consent.
> 

I am reworking my previous patch series (from when I 'reverse
engineered' the new enum values) to reflect the new SDK and I'll resend
later this week. It will include updates for cuviddec.

Thanks,

--phil