[FFmpeg-devel] [PATCH 1/2] qsvdec: add support for HW_DEVICE_CTX method

[Xiang, Haihao]

On Thu, 2021-06-24 at 01:33 +0000, Xiang, Haihao wrote:
> On Wed, 2021-06-23 at 16:41 +0000, Soft Works wrote:
> > 
> > -----Original Message-----
> > From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of Haihao
> > Xiang
> > Sent: Mittwoch, 23. Juni 2021 05:04
> > To: ffmpeg-devel at ffmpeg.org
> > Cc: Haihao Xiang <haihao.xiang at intel.com>
> > Subject: [FFmpeg-devel] [PATCH 1/2] qsvdec: add support for HW_DEVICE_CTX
> > method
> > 
> > This allows user set hw_device_ctx instead of hw_frames_ctx for QSV
> > decoders,
> > hence we may remove the ad-hoc libmfx setup code from FFmpeg.
> > 
> > "-hwaccel_output_format format" is applied to QSV decoders after removing
> > the
> > ad-hoc libmfx code. In order to keep compatibility with old commandlines,
> > the
> > default format is set to AV_PIX_FMT_QSV, but this behavior will be removed
> > in
> > the future. Please set "-hwaccel_output_format qsv"
> > explicitly if AV_PIX_FMT_QSV is expected.
> > 
> > The normal device stuff works for QSV decoders now, user may use "-
> > init_hw_device args" to initialise device and "-hwaccel_device devicename"
> > to
> > select a device for QSV decoders. "-qsv_device device"
> > which was added for workarounding device selection in the ad-hoc libmfx code
> > is deprecated and will be removed from FFmpeg.
> > 
> > For example:
> > 
> > $> ffmpeg -init_hw_device vaapi=va:/dev/dri/card0 -init_hw_device qsv=hw at va
> > -hwaccel qsv -c:v h264_qsv -i input.h264 -f null -
> > 
> > /dev/dri/renderD128 is actually open for h264_qsv decoder in the above
> > command
> > without this patch. After applying this patch, /dev/dri/card0 is used.
> > 
> > $> ffmpeg -init_hw_device vaapi=va:/dev/dri/card0 -init_hw_device qsv=hw at va
> > -hwaccel_device hw -hwaccel qsv -c:v h264_qsv -i input.h264 -f null -
> > 
> > device hw of type qsv is not usable in the above command without this patch.
> > After applying this patch, this command works as expected.
> > ---
> > 
> > Haihao,
> > 
> > I think, from all the not-yet-merged QSV patches, this is the most important
> > one.
> > I'll try to find some time to review shortly.
> 
> Thanks for helping to review this patch, and any comment is welcome. 
> 
> > 
> > Is this patch independent of your other submitted patches?
> 
> Yes, this patch is independent of other patches and you may apply it to the
> latest master branch directly. 
> 
> BTW the fix in 
> http://ffmpeg.org/pipermail/ffmpeg-devel/2021-February/276695.html is no
> longer
> needed after applying this patch. The command  works for me if using
> -init_hw_device qsv=qsv at intel to create the connection between vaapi and
> QSVdevices. 
> 

Hi Softworkz,

May I know if there is any regression when you tried this patchset? Note this
patchset can't be applied to the latest master branch because there is a
conflict with the change on master. I will submit a new version of this
patchset. 

Thanks
Haihao