The vector dequantization has a test in a loop preventing effective SIMD
implementation. By moving it out of the loop, this loop can be DSPized.
Therefore, modify the current DSP implementation. In particular, the
DSP implementation no longer has to handle null loop sizes.
The decode_hf implementations have following timings:
For x86 Arrandale:
C SSE SSE2 SSE4
win32: 260 162 119 104
win64: 242 N/A 89 72
The arm NEON optimizations follow in a later patch as external asm. The
now unused check for the y modifier in arm inline asm is removed from
configure.
Based on a patch from Christophe Gisquet.
Unrolling of the m == 0 case avoids a possible use of the uninitilized
value sum when s->predictor_history is not set. I failed to find a
sample for it. It also reduced the cycle count from 220 to 150 on
sandy bridge, x86_64 linux, gcc 4.8.2 compared to his patch.
Timings for Arrandale:
C SSE
win32: 2108 334
win64: 1152 322
Factorizing the inner loop with a call/jmp is a >15 cycles cost, even with
the jmp destination being aligned.
Unrolling for ARCH_X86_64 is a 20 cycles gain.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
The scaling factor is constant so it is faster to scale the
FIR coefficients in the tables during compilation.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
There's an SSE2 version as well, and x86_64 guarantees that
instruction set is present.
Signed-off-by: James Almer <jamrial@gmail.com>
Reviewed-by: "Ronald S. Bultje" <rsbultje@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Also fail if AV_EF_EXPLODE is set.
We do not fail by default, but rather return some image as it may be usefull to the
end user to see what is on the image, for example text could be read quite fine and
objects recognized.
Possibly fixes Ticket3424
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Framerate is now a sane rational instead of an integer, and
inputDepth is changed to what it actually is.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Framerate is now a sane rational instead of an integer, and
inputDepth is changed to what it actually is.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
* qatar/master:
Use av_frame_copy() to simplify code where appropriate.
Conflicts:
libavfilter/vf_copy.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* commit '8feac29cc46270cc89d6016340e7bac780877131':
lavc: use AVFrame API properly in ff_reget_buffer()
Merged-by: Michael Niedermayer <michaelni@gmx.at>
We need the emulation to support the cases where the first
argument is the same as the fourth. To achieve this a fifth
argument working as a temporary may be needed.
Emulation that doesn't obey the original instruction semantics
can't be in x86inc.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
