Change bitreading functions to use a larger window which is refilled less
often.
This makes it cheap enough to do bounds checking each time the window is
refilled, which avoids the need to copy the input into a large circular
buffer.
This uses less memory and speeds up the total decode time by 1.6% on an ARM11,
2.8% on a Cortex A8, and 2.2% on x86-32, but less than 1% on x86-64.
Inlining vp8dx_bool_decoder_fill() has a big penalty on x86-32, as does moving
the refill loop to the front of vp8dx_decode_bool().
However, having the refill loop between computation of the split values and
the branch in vp8_decode_mb_tokens() is a big win on ARM (presumably due to
memory latency and code size: refilling after normalization duplicates the
code in the DECODE_AND_BRANCH_IF_ZERO and DECODE_AND_LOOP_IF_ZERO cases.
Unfortunately, refilling at the end of vp8dx_bool_decoder_fill() and at the
beginning of each decode step in vp8_decode_mb_tokens() means the latter
requires an extra refill at the end.
Platform-specific versions could avoid the problem, but would require most of
detokenize.c to be duplicated.
Change-Id: I16c782a63376f2a15b78f8086d899b987204c1c7
Restructure vp8_sixtap_predict functions to eliminate extra 5-line
calculation while doing first-pass only. Also, combline functions
to eliminate usage of intermediate buffer. This gives decoder a 3%
performance gain on my test clips.
Change-Id: I13de49638884d1a57d0855c63aea719316d08c1b
This patch removes the secondary MV clamping from the MV decoder. This
behavior was consistent with limits placed on non-split MVs by the
reference encoder, but was inconsistent with the MVs generated in the
split case.
The purpose of this secondary clamping was only to prevent crashes on
invalid data. It was not intended to be a behaviour an encoder could or
should rely on. Instead of doing additional clamping in a way that
changes the entropy context, the secondary clamp is removed and the
border handling is made implmentation specific. With respect to the
spec, the border is treated as essentially infinite, limited only by
the clamping performed on the near/nearest reference and the maximum
encodable magnitude of the residual MV.
This does not affect any currently produced streams.
Change-Id: I68d35a2fbb51570d6569eab4ad233961405230a3
This renames the vpx_codec/ directory to vpx/, to allow applications
to more consistently reference these includes with the vpx/ prefix.
This allows the includes to be installed in /usr/local/include/vpx
rather than polluting the system includes directory with an
excessive number of includes.
Change-Id: I7b0652a20543d93f38f421c60b0bbccde4d61b4f
This doesn't play well with autotools, and the preprocessor magic is
confusing and unhelpful in the vp8-only context.
Change-Id: I2fcb57e6eb7876ecb58509da608dc21f26077ff1
