U contributes to B and G.  V contributes to R and G.
By swapping U and V, they contribute to the opposite channels.  Adjust the matrix so the U contribution is in the matrix location such that it till contribute to the
new B channel and vice versa.
This allows ABGR versions of YUV conversion to use the same low level code as ARGB, just using a different matrix and swapping U and V pointers.

As a result the existing I444ToABGRRow functions are no longer needed and are removed.

Previously this function was only Intel AVX2 optimized for Windwos.  Now it is also optimized for Arm and GCC.

ARMv7 Neon
Was LibYUVConvertTest.I444ToABGR_Opt (75971 ms)
Now LibYUVConvertTest.I444ToABGR_Opt (3672 ms)
20.6 times faster.

R=xhwang@chromium.org
BUG=libyuv:515

Review URL: https://codereview.chromium.org/1414133006 .

TBR=harryjin@google.com
BUG=libyuv:515

Review URL: https://codereview.chromium.org/1423663007 .

R=harryjin@google.com
BUG=libyuv:514

Review URL: https://codereview.chromium.org/1413463004 .

R=harryjin@google.com
BUG=libyuv:512

Review URL: https://codereview.chromium.org/1418253002 .

R=harryjin@google.com
BUG=libyuv:512

Review URL: https://codereview.chromium.org/1422733003 .

R=harryjin@google.com
BUG=libyuv:511

Review URL: https://codereview.chromium.org/1412683005 .

TBR=harryjin@google.com
BUG=libyuv:510

Review URL: https://codereview.chromium.org/1415583003 .

A bug was introduced on arm when the code for 'any' width switch to
a temporary stack buffer and simd.
The C version handles odd width by doing 1 pixel, instead of averaging 2.
But the SIMD any version is supposed to replicate the last pixel, then
the subsampling in Neon will average the pixel with itself, producing
the same result.
The previous version did this, but only for ARGB 32 bit, which was to
avoid introducing issues with subsampled YUY2 source.  This CL adds
replication for RGB 16 bit values.

TBR=harryjin@google.com
BUG=libyuv:510

Review URL: https://codereview.chromium.org/1418983003 .

TBR=harryjin@google.com
BUG=none

Review URL: https://codereview.chromium.org/1415213002 .

The any function for handling ARGBToI411 was not handling the pixel
replication correctly.  On 422 and odd width was handled by duplicating
a pixel of source.  411 needs replication for remainders of 1, 2 or 3
pixels.

The C version was handling odd width but with an average of the remainder
pixels, which does not match the SIMD 'any' handling off remainder.
This changes the odd width handling to mimic the any version.

TBR=harryjin@google.com
BUG=libyuv:491

Review URL: https://codereview.chromium.org/1411733004 .

Fix compile error on arm, mips etc due to undefined variable.

TBR=harryjin@google.com
BUG=none

Review URL: https://codereview.chromium.org/1403373008 .

To make init cpu flags thread safe, there can only be one write to the variable.

R=richard.winterton@intel.com, harryjin@google.com
BUG=libyuv:508

Review URL: https://codereview.chromium.org/1412793006 .

A fix for android -a was checked in, allowing libyuv gtest flags to be pass.
This CL rolls to the head version of chromium to pull in the change,
allowing better testing and benchmarking of libyuv on android.

TBR=harryjin@google.com
BUG=libyuv:507

Review URL: https://codereview.chromium.org/1416663006 .

Changelog: https://chromium.googlesource.com/chromium/src/+log/bb79186..5d149df

TBR=fbarchard@chromium.org

Review URL: https://codereview.chromium.org/1416823002 .

Allows us to ignore flags passed on to us by Chromium build bots
without having to explicitly disable them. (Thanks pbos!)

TESTED=webrtc ran modules_unittests with a bogus flag did not result in an
error.

R=kjellander@chromium.org
BUG=libyuv:507

Review URL: https://codereview.chromium.org/1417573002 .

The DEPS entry for gflags added in https://codereview.chromium.org/1413723002/
assumed the Chromium/WebRTC checkout layout with 'src' as the
top-directory name. That doesn't work for libyuv, since the top-directory
is named 'libyuv'.

BUG=libyuv:507

Review URL: https://codereview.chromium.org/1410673004 .

files needed for command line support with gtest.
These files are copied directly from webrtc.

TBR=kjellander@chromium.org
BUG=libyuv:507

Review URL: https://codereview.chromium.org/1414483002 .

Unit tests currently use environment variables to change behavior.
Using gflags this can be done via command line.

BUG=libyuv:507
TBR=fbarchard@chromium.org

Review URL: https://codereview.chromium.org/1413723002 .

This reverts commit 2dd3d923.

Reason: chromium_git is a missing variable, and to properly
add gflags, we need to check in GYP files in third_party/gflags
first, then add the DEPS entry.

BUG=libyuv:507
TBR=fbarchard@chromium.org

Review URL: https://codereview.chromium.org/1406323002 .

unittests currently use environment variables to change behavior.
using gflags this can be done via command line.

R=kjellander@chromium.org
BUG=libyuv:507

Review URL: https://codereview.chromium.org/1402313002 .

This test is just a printf, not a real test, but somehow
fails on arm.

TBR=harryjin@google.com
BUG=libyuv:506

Review URL: https://codereview.chromium.org/1409913002 .

R=harryjin@google.com
BUG=libyuv:507

Review URL: https://codereview.chromium.org/1410643002 .

YuvPixel for arm was miscomputing YG.

TBR=harryjin@google.com
BUG=libyuv:506

Review URL: https://codereview.chromium.org/1402333002 .

TBR=harryjin@google.com
BUG=libyuv:506

Review URL: https://codereview.chromium.org/1403183002 .

A hang in color conversion on arm occurs somewhere in yuv to rgb.
Breaking the color test into its own category of test will help
run selective tests to narrow down the issue.

R=harryjin@google.com
BUG=libyuv:506

Review URL: https://codereview.chromium.org/1405543003 .

These tests are place holders, but cause a hang on arm.
Disable them for now.

TBR=harryjin@google.com
BUG=libyuv:506

Review URL: https://codereview.chromium.org/1407693003 .

R=sergeyu@chromium.org
BUG=chromium:538243

Review URL: https://codereview.chromium.org/1396363004 .

R=harryjin@google.com
BUG=none

Review URL: https://codereview.chromium.org/1399523004 .

Roll chromium_revision bfea27a..bb79186 (340499:353481) in DEPS.
Changes: https://chromium.googlesource.com/chromium/src/+log/bfea27a..bb79186

To get the Android dependencies, you need to have
target_os = ["android"];
added to the end of your .gclient file (after the solution specs)
+ re-run gclient sync.
You'll also need to run: build/install-android-sdks.sh

Then build and run the test with something like this:
GYP_CROSSCOMPILE=1 GYP_DEFINES="OS=android component=static_library target_arch=arm" ./gyp_libyuv
ninja -C out/Release libyuv_unittest_apk
util/android/test_runner.py gtest -s libyuv_unittest --verbose --release

R=fbarchard@chromium.org

Review URL: https://codereview.chromium.org/1398383003 .

PNaCl code validation fails when compiling with -O0 due to the linked
bug. Always enable optimization when compiling for NaCl to workaround
this bug.

BUG=538243
R=fbarchard@chromium.org

Review URL: https://codereview.chromium.org/1403813002 .

fill in aarch64 yuv constants to match how the code expects them.

TBR=harryjin@google.com
BUG=libyuv:502

Review URL: https://codereview.chromium.org/1396253004 .

TBR=harryjin@google.com
BUG=none

Review URL: https://codereview.chromium.org/1398633002 .

previously the neon source code was broken into a separate
library built with -mfpu=neon for the neon assembly, while
the C code was built without neon.

In this change, the neon code is added to the main library
and all code built with neon.

TBR=harryjin@google.com
BUG=libyuv:371

Review URL: https://codereview.chromium.org/1392043003 .

yuv constants for bt.601 were previously ported to neon64, as well
as the code to respect other color spaces.  But the jpeg and bt.709
colour conversion constants were still in armv7 form.  This changes
the constants for aarch64 builds to be compatible with the code.

yuv constants are now passed as const *

Remove Yvu constants which were used for older version on nv21 but not new code.

TBR=harryjin@google.com
BUG=none

Review URL: https://codereview.chromium.org/1398623002 .

Fix for 64 bit gcc parameter in dither function which requires m not r,
when ABI uses register.

BUG=none

Review URL: https://codereview.chromium.org/1399463002 .

Previously the assembly code was only available to Windows.
This CL ports the AVX2 code to GCC syntax.

TBR=harryjin@google.com
BUG=libyuv:492

Review URL: https://codereview.chromium.org/1391273003 .

Previously the assembly code was only available to Windows.
This CL ports the SSE2 code to GCC syntax.

When running a profiler on all the unittests, this function
was the slowest of all functions that still ran in C code.
   3.71%  libyuv_unittest  libyuv_unittest      [.] ARGBToRGB565DitherRow_C

Was
ARGBToRGB565Dither_Opt (2894 ms)
Now
ARGBToRGB565Dither_Opt (432 ms)

TBR=harryjin@google.com
BUG=libyuv:492

Review URL: https://codereview.chromium.org/1397673002 .

offset to second group of pixels was off by 16.
should have been 32, not 16.
requires avx2 hardware and wide image for test.

R=harryjin@google.com
TBR=harryjin@google.com
BUG=libyuv:492,libyuv:501

Review URL: https://codereview.chromium.org/1395603002 .

SETUP provided by zhongwei.yao@linaro.org

Previously the 64 bit Neon code had hard coded constants in the setup macro
for YUV conversion, while 32 bit Neon code supported the yuvconstants
parameter.

This change accepts the constants passed to the YUV conversion row function,
allowing different color spaces to be respected - naming JPEG and BT.709.
As well as the existing BT.601.

TBR=harryjin@google.com
BUG=libyuv:472

Review URL: https://codereview.chromium.org/1384323002 .

Low level for NV21ToARGB written to accept yuv matrix used by
other YUV to ARGB functions.
Previously NV21 was implemented for Windows using NV12 with a different
matrix that swapped U and V.  But the Arm version of the low level does
not allow the matrix U and V contributions to be swapped.
Using a new low level function that reads NV21 and uses the same
yuvconstants as other YUV conversion functions allows an Arm port of
this function.

TBR=harryjin@google.com
BUG=libyuv:500

Review URL: https://codereview.chromium.org/1388273002 .