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

[Soft Works]

-----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.

Is this patch independent of your other submitted patches?

softworkz