It is used as get_bits argument and reading 0 bits doesn't make sense.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This prevents possible infinite loops with the calling code along the
lines of while (bytestream2_get_bytes_left()) { ... }, where the reader
does not advance.
CC: libav-stable@libav.org
It provides the following features:
* verify correctness by comparing output to the C version.
* detect failure to save and restore clobbered callee-saved registers.
* detect 32-bit parameters being used as if they were 64-bit in x86-64
(the upper halves are not guaranteed to be zero - but in practice
they very often are, which makes those bugs hard to spot otherwise).
* easy benchmarking.
Compile by running 'make checkasm'.
Execute by running 'tests/checkasm/checkasm'.
Optional arguments are '--bench' to run benchmarks for all functions,
'--bench=<pattern>' to run benchmarks for all functions that starts with
<pattern>, and '<integer>' to seed the PRNG for reproducible results.
Contains unit tests for most h264pred functions to get started, more tests
can be added afterwards using those as a reference.
Loosely based on code from x264. Currently only supports x86 and x86-64,
but additional architectures shouldn't be too much of an obstacle to add.
Note that functions with floating point parameters or floating point
return values are not supported. Some compiler-specific features or
preprocessor hacks would likely be required to add support for that.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
flcoeffs2[pos] should be the log2 of flcoeffs1[pos].
flcoeffs1[0] can be 0 here, thus flcoeffs2[pos] gets set to -inf,
causing problems further down.
This seems to have been copied from imc_decode_level_coefficients in
commit 4eb4bb3 without updating the position.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Improves the accuracy of measurements, especially in short sections.
To quote the Intel 64 and IA-32 Architectures Software Developer's Manual:
"The RDTSC instruction is not a serializing instruction. It does not necessarily
wait until all previous instructions have been executed before reading the counter.
Similarly, subsequent instructions may begin execution before the read operation
is performed. If software requires RDTSC to be executed only after all previous
instructions have completed locally, it can either use RDTSCP (if the processor
supports that instruction) or execute the sequence LFENCE;RDTSC."
SSE2 is a requirement for lfence so only use it on SSE2-capable systems.
Prefer lfence;rdtsc over rdtscp since rdtscp is supported on fewer systems.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Avoid possible issues with memmapped hardware buffers in
case VDA is not doing a conversion on behalf of the user
and make the code more proper as working example.
CC: libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Freeze picture release should be set to 1 when we're responding to a
fast update request. For simplicity we set it for all intra frames,
including those that starts a GOP.
Fixes issue where Tandberg MXP1700 does not recover from packet loss
state since it's waiting for the freeze picture relase indication.
Bug-Id: 873
CC: libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Ref H.261 recommendation section 4.2.1.3, setting the still image flag
to 1 disables still image mode. Some decoders require this in order to
decode the bitstream as normal video.
Fixes H.261 calls to Cisco E20.
Also, reserved (aka spare) bits should be set to 1 unless specified
otherwise.
Bug-Id: 872
CC: libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Every chunk needs at least 8 bytes for chunk_type and chunk_size.
Prevent a possible infinite loop.
CC: libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
They are used by dnxhd and mpegvideo_enc exclusively, move them to codec
private options instead.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This returns something like "v12_dev0-1332-g333a27c". This is much more
useful than the individual library versions, of which there are too
many, and which are very hard to map back to releases or git commits.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
Fix warning from clang "absolute value function 'abs' given an argument
of type 'long long' but has parameter of type 'int' which may cause
truncation of value [-Wabsolute-value]".
