Fixes the following ubsan errors with the sample from ticket #7980:
libavcodec/zmbvenc.c:243:29: runtime error: left shift of negative value -4
libavcodec/zmbvenc.c:244:28: runtime error: left shift of negative value -2
This consists mostly of the following changes:
- add newly supported pixel formats (RGB555LE, RGB565LE, BGR0)
- select the ZMBV format (c->fmt) and bytes per pixel (c->bypp) based on
avctx->pix_fmt
- multiply widths/x-values by c->bypp, in places where bytes, not pixels, are
expected
- disable palette-writing code for non-palette pix_fmts
- make a note about histogram[]'s datatype (it could need increasing if
ZMBV_BLOCK is increased)
- adjust the c->score_tab length to take up to (and including) 4 times the
number of pixels in a block
- initialise c->score_tab up to c->bypp * the number of pixels
Note: the ZmbvFormat enum allows for additional bit depths:
- 1,2,4-bit (palette)
- 24-bit (RGB)
At time of writing the specifics of these (e.g. channel order, bit alignment)
are not currently defined, and DOSBox only implements support for 8/15/16/32
bpp.
One might expect the 24-bit format - if implemented - to be BGR24, to have the
same channel order as BGR0.
However, the decoder in zmbv.c has been guessed to use RGB24, so I have chosen
to not contradict this, and omitted specific support for this format.
- Clamp ME range to -64..63 (prevents corruption when me_range is too high)
- Allow MV's up to *and including* the positive range limit
- Allow out-of-edge ME by padding the prev buffer with a border of 0's
- Try previous MV before checking the rest (improves speed in some cases)
- More robust logic in code - ensure *mx,*my,*xored are updated together
- Improve block choices by counting 0-bytes in the entropy score
- Make histogram use uint16_t type, to allow byte counts from 16*16
(current block size) up to 255*255 (maximum allowed 8bpp block size)
- Make sure score table is big enough for a full block's worth of bytes
- Calculate *xored without using code in inner loop
This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This parameter can be used to inform the allocation code about how much
downsizing might occur, and can be used to optimize how to allocate the
packet
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The rationale is that coded_frame was only used to communicate key_frame,
pict_type and quality to the caller, as well as a few other random fields,
in a non predictable, let alone consistent way.
There was agreement that there was no use case for coded_frame, as it is
a full-sized AVFrame container used for just 2-3 int-sized properties,
which shouldn't even belong into the AVCodecContext in the first place.
The appropriate AVPacket flag can be used instead of key_frame, while
quality is exported with the new AVPacketSideData quality factor.
There is no replacement for the other fields as they were unreliable,
mishandled or just not used at all.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Allocating coded_frame is what most encoders do anyway, so it makes
sense to always allocate and free it in a single place. Moreover a lot
of encoders freed the frame with av_freep() instead of the correct API
av_frame_free().
This bring uniformity to encoder behaviour and prevents applications
from erroneusly accessing this field when not allocated. Additionally
this helps isolating encoders that export information with coded_frame,
and heavily simplifies its deprecation.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Also break some long lines, remove codec function placeholder comments
and add spaces in sample/pixel format lists.
Signed-off-by: Martin Storsjö <martin@martin.st>
None of these symbols should be accessed directly, so declare them as
hidden.
Signed-off-by: Mans Rullgard <mans@mansr.com>
(cherry picked from commit d36beb3f69)
Passing an explicit filename to this command is only necessary if the
documentation in the @file block refers to a file different from the
one the block resides in.
Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk
XORed with source one or not, which went wrong with new block comparing code.
So track this condition explicitly.
Originally committed as revision 20558 to svn://svn.ffmpeg.org/ffmpeg/trunk
Otherwise doxygen complains about ambiguous filenames when files exist
under the same name in different subdirectories.
Originally committed as revision 16912 to svn://svn.ffmpeg.org/ffmpeg/trunk
Carl Eugen Hoyos
Matthew Fearnley
Anton Khirnov
Ganesh Ajjanagadde
Michael Niedermayer
Vittorio Giovara
Gabriel Dume
Diego Biurrun
Paul B Mahol
Martin Storsjö
Michael Niedermayer
Mans Rullgard
Clément Bœsch
Stefano Sabatini
Diego Elio Pettenò
Kostya Shishkov
Reimar Döffinger
David Conrad
Benjamin Larsson
Carl Eugen Hoyos