Old Intel GPUs expect the reference frame index to the actual surface,
instead of the index into RefFrameList as specified by the spec.

This workaround should be set when using one of the "ClearVideo" decoder
devices.
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Old Intel GPUs expect the reference frame index to the actual surface,
instead of the index into RefFrameList as specified by the spec.

This workaround should be set when using one of the "ClearVideo" decoder
devices.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This removes duplicate code
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

The workaround needs to be enabled per PCI ID which cannot be detected inside
libavcodec. So add a flag to manually enable the alternate behavior.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

The workaround need to be enabled per pci id which can not
be detected inside ffmpeg. So this adds a flag that enabled
the alternate behavior.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Mans Rullgard <mans@mansr.com>

 It allows VLD H264 decoding using DXVA2 (GPU assisted decoding API under
VISTA and Windows 7).
 It is implemented by using AVHWAccel API. It has been tested successfully
for some time in VLC using an nvidia card on Windows 7.

 To compile it, you need to have the system header dxva2api.h (either from
microsoft or using http://downloads.videolan.org/pub/videolan/testing/contrib/dxva2api.h)
 The generated libavcodec.dll does not depend directly on any new lib as
the necessary objects are given by the application using FFmpeg.

Originally committed as revision 21353 to svn://svn.ffmpeg.org/ffmpeg/trunk