Issues with the code:
1) The skip_bits_long breaks packed B-frames since we skip
of the packed frame, even for VDPAU.
2) Calling ff_h263_find_resync_marker_reverse is nonsense for MPEG-4,
and for H.263 the only code using this (vaapi_mpeg4) explicitly reverts
this change!
3) mb_x/mb_y are always 0 when vaapi_mpeg4_decode_slice, so doing
computations with them is just obfuscation
4) due to not updating mb_y the code would always go into the error
resilience case, causing nonsense error messages and maybe further
issues.
While tested to fix the data provided to the decoder in case of
VDPAU so it is the same as for the non-hwaccel code, the VA-API code
was not tested to still work, and adding regression testing even
as a quick hack is much more complicated for it.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Most of the changes are just trivial are just trivial replacements of
fields from MpegEncContext with equivalent fields in H264Context.
Everything in h264* other than h264.c are those trivial changes.
The nontrivial parts are:
1) extracting a simplified version of the frame management code from
mpegvideo.c. We don't need last/next_picture anymore, since h264 uses
its own more complex system already and those were set only to appease
the mpegvideo parts.
2) some tables that need to be allocated/freed in appropriate places.
3) hwaccels -- mostly trivial replacements.
for dxva, the draw_horiz_band() call is moved from
ff_dxva2_common_end_frame() to per-codec end_frame() callbacks,
because it's now different for h264 and MpegEncContext-based
decoders.
4) svq3 -- it does not use h264 complex reference system, so I just
added some very simplistic frame management instead and dropped the
use of ff_h264_frame_start(). Because of this I also had to move some
initialization code to svq3.
Additional fixes for chroma format and bit depth changes by
Janne Grunau <janne-libav@jannau.net>
Signed-off-by: Anton Khirnov <anton@khirnov.net>