[ffmpeg-qsv][h264_ffmpeg]decode dump file has garbage on iHD driver.

[a]

Summary of the bug:
How to reproduce:

1.ffmpeg -hwaccel qsv -hwaccel_device /dev/dri/renderD128 -v verbose -y -c:v h264_qsv -i /media//ffmpeg_h264/crop-to-container-dims-canon.mov -vf hwdownload,format=nv12 -pix_fmt yuv420p -f rawvideo -y dump.yuv -vsync 0
2. 7yuv to open dump.yuv
ffmpeg version : N-91726-g56f68a0

bug descript

The dump file md5 is not equal to reference, and the dump file has garbage.

[a]

failed case

/media/ffmpeg_h264/crop-to-container-dims-canon.mov
/media/ffmpeg_h264/H264_might_overflow.mkv

[a]

SKL OS: ubuntu 16.04 kernel: 4.15.0
libva b6c50dad4d7d14c507108d9f468662e2d7ae1c4d ​https://github.com/01org/libva.git
VPG_Driver ed04556a6676fd77ff845508bc54bfc60915450c ​https://github.com/intel/media-driver
libva-utils 9a10ad663349732decd668a426cfc349b0010d1d ​https://github.com/01org/libva-utils.git
Mediasdk 7ea683585f0f84f1bea035a405855312c92c46c0 ​https://github.com/Intel-Media-SDK/MediaSDK
FFMPEG 56f68a099cc607658118e00cad30569103ae3751 ​https://git.ffmpeg.org/ffmpeg.git

[jkqxz]

This seems to work for me? Or at least, I don't get garbage in the output.

It isn't bit-exact because the input is full-range and libmfx doesn't seem to have any way of communicating that, but the data is correct. (Decoding with iHD directly via VAAPI supports the range signalling and therefore matches software behaviour exactly, so this is only a libmfx problem.)

[Linjie.Fu]

Tested with the latest version of MSDK： c083a2724b99851af6d69bbb35e3130b39a1f702

$ ffmpeg -i crop-to-container-dims-canon.mov -c:v copy src.h264
$ ./sample_decode h264 -i src.h264 -i420 -o msdk.yuv

ffmpeg -hwaccel qsv -hwaccel_device /dev/dri/renderD128 -v verbose -y -c:v h264_qsv -i crop-to-container-dims-canon.mov -vf hwdownload,format=nv12 -pix_fmt yuv420p -f rawvideo -y dump.yuv -vsync 0

Both msdk.yuv and dump.yuv have garbage in my test.

Report an issue in MediaSDK：
​https://github.com/Intel-Media-SDK/MediaSDK/issues/715

[a]

dump.yuv don't have garbage on latest code base.

[Carl Eugen Hoyos]

Please add the commit that fixed the issue.