The earlier code had two problems:
1. For reference frames that are not directly output (happens unless
low_delay is set), the mb skip values referred to the next reference
frame to be decoded.
2. For non-reference frames, every macroblock was always considered
skipped.
This makes the output (worse than) useless; that no one ever
complained about this shows that this feature is not really used.
It is therefore removed.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
MB_TYPE_L[01] is based upon H.264 terminology (it stands for
list); yet the mpegvideo based decoders don't have lists
of reference frames, they have at most one forward and one
backward reference. So use terminology based upon this.
This also has a second advantage: MB_TYPE_L[01] is actually
an OR of two flags (which are set independently for H.264,
but aren't for mpegvideo). Switching to different flags
makes the flags fit into an int16_t, which will be useful
in future commits.
The only downside to this is a very small amount of code
in error_resilience.c and mpegutils.c (the only code shared
between the H.264 decoder and mpegvideo).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Do this to make MB_TYPE_{CBP,QUANT} fit into an int16_t,
so that can be used in a VLC symbol table.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
MB_TYPE_ACPRED is currently reused for MB_TYPE_REF0 by H.264,
so that the value fits into an uint16_t. Given that MB_TYPE_ACPRED
is not subject to any such restriction (apart from fitting into
32bits), it can be remapped to a hithereto unused bit.
The then available bit will be declared to be codec-specific
(i.e. unused by generic code), so that H.264 can use it
for MB_TYPE_REF0 and so that it can be reused later for
e.g. MB_TYPE_H261_FIL.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is only used by the H.264 decoder (as well as the dirac decoder,
which already uses a local copy).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
These have mostly been added because of FF_API_*; yet when these were
removed, removing the header has been forgotten.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>