Create LUT for PrefixEncode.

This speeds up lossless compression by 5%.
Change-Id: Ifd114b1d9850dc3aac74593809e7d48529d35e3d
bit_reader.h: cosmetics

- use const where applicable
- drop unnecessary string.h include

Change-Id: I560eef84fe17d3925768f6817c02ea79604c4379
slightly faster ParseIntraMode

+ cosmetics

Change-Id: Icb906d5f84f025ef9e04b71a73801a22cc990ee5
Merge "slightly faster ParseIntraMode"
Support for "Do not blend" in mux and demux libraries

Change-Id: I9566a8e2d059fe1ebd9ca99c7e13311bf3f8f281
Pack code & extra_bits to Struct (VP8LPrefixCode).

Also created variant VP8LPrefixEncodeBits that returns the
code & extra_bits only.
There's no impact on compression density and compression speed.

Change-Id: I2cafdd3438ac9270cd72ad9d57b383cdddfdfa4c
Merge "Support for "Do not blend" in mux and demux libraries"
Animated WebP: add "do no blend" option to spec

Marking certain frames as "do not blend" helps avoiding alpha-blending
at decode/render time.

It also helps inserting I-frames (frames which can be independently
decoded) into the animation.

Change-Id: Iaa222805db88d2f1c81104ce9d882e7c7ff8cfdb
Support for 'do not blend' option in vwebp

Change-Id: I563e192fa727816d11d8647c559ec407205ef40b
Merge "Support for 'do not blend' option in vwebp"
fix const-ness

Change-Id: I09c85fdb90b4380c8fc03c8b5652bb9cf29b2021
cosmetics

Change-Id: Ib6fa2a7e1db8c5c48607c7097520ffca34a6cb66
Merge "bit_reader.h: cosmetics"
Merge "cosmetics"
dsp: msvc compatibility

intrin.h is available after VS2003

patch from the FreeImage project

Change-Id: I58a18a0db00e247f871d05e3ba99772704f0e079
output to stdout if file name is "-"

Doesn't work with WIC

+ redirect some info messages from stdout to stderr
+ fix the error reporting upon output-writing error

Change-Id: I92b8bd7a15e656a3f3cdfbf56299f024e39453f8
simplify upsampler calls: only allow 'bottom' to be NULL

If 'top' was meant to be NULL, then bottom and top can be
swapped. Logic is simpler.

+ fix compilation in non-FANCY_UPSAMPLING mode

Change-Id: I7c62bbb59454017f072c0945d1ff2d24d89286ff
5-7% faster SSE2 versions of YUV->RGB conversion functions

The C-version gets ~7-8% slower in order to match the SSE2
output exactly. The old (now off-by-1) code is kept under
the WEBP_YUV_USE_TABLE flag for reference.

(note that calc rounding precision is slightly better ~= +0.02dB)

on ARM-neon, we somehow recover the ~4% speed that was lost by mimicking
the initial C-version (see https://gerrit.chromium.org/gerrit/#/c/41610)

Change-Id: Ia4363c5ed9b4c9edff5d932b002e57bb7814bf6f
Merge "simplify upsampler calls: only allow 'bottom' to be NULL"
Merge "5-7% faster SSE2 versions of YUV->RGB conversion functions"