QSV Decoding + Video Post Processing (VPP) support

[TheTroll]

Summary of the bug:
The latest GIT as of 2015-06-22 supports QSV encoding quite properly.

Though QSV decoding does not work at all.
In addition, there is no use of the VPP functions (like deinterlacing, scaling,...).

It would be nice to have this working, to do a fully HW accelerated transcoding.

[Carl Eugen Hoyos]

Replying to TheTroll:

Though QSV decoding does not work at all.

Is this a regression or did it never work?

[Timo R.]

As far as i'm aware, there is not and never was a qsv based decoder.
Hardware decoding is done via DXVA on Windows.

[TheTroll]

Well there is a qsvdec_h264.c file...
The implementation misses some key calls like the DecodeHeader function for instance.

So if it has indeed worked, I am not sure how.. or only in in a very specific situation

[TheTroll]

Examples on how to do VPP and decoding are in the file:

MediaSamples_Linux_6.0.16043138.138

that you can get from intel site.

HW encoding is great, I can transcode from 1080i H264 from 720p H264, using ~0% CPU for the encoding part.

Though, decoding+deinterlacing+scaling takes almosy 30% CPU on a Core i7-4790k :/

[bordon]

Hope the offical can add QSV Decoding function as soos as possible.

[TheTroll]

Hey,

coming back on this thread, QSV decoding works now quite well:
Try the following :

ffmpeg -c:v h264_qsv -i in_h264.ts -b:v 1000k -maxrate 1000k -c:v h264_qsv out_qsv.ts

[Zhong,Li]

VPP is supported from FFmpeg 3.3, scaling and deinterlacing filters were supported. And from ffmpeg 4.0, qsv overlay was supported.
Here is an example of a qsv transcoding pipeline with decoding/scaling/encoding:
ffmpeg -hwaccel qsv -c:v h264_qsv -i "testvid.mp4" -vf "scale_qsv=640:360" -b:v 800k -c:v h264_qsv -c:a copy -y "testoutput.mp4"