Change-Id: Iccb75d5204f0f52f2c7d6e18d1f8223ce10f68ba

* changes:
  Fix warnings reported by -Wshadow: Part4: main directory
  Fix warnings reported by -Wshadow: Part3: test/ directory
  Fix warnings reported by -Wshadow: Part2b: more from av1 directory
  Fix warnings reported by -Wshadow: Part2: av1 directory
  Fix warnings reported by -Wshadow: Part1b: scan_order struct and variable
  Fix warnings reported by -Wshadow: Part1: aom_dsp directory
  Move STAT_TYPE enum to source file.
  Code cleanup: mainly rd_pick_partition and methods called from there.

Now that all warnings are taken care of, add warning flag -Wshadow to
configure.

Note: Enabling this flag for C++ generates some useless warnings about
some function parameters shadowing class member function names. So, only
enabling this warning for C code.

Cherry-picked from aomedia/master: b96cbc44

Change-Id: I3922dea2e6976b16519c4aa4d1bd395c198134f1

The tx_partition_set_contexts function changes tx_size even
for blocks coded with a rectangular transform.
This causes an internal rd inconsistency when using all of
CONFIG_VAR_TX, CONFIG_RECT_TX, CONFIG_EXT_TX.

Change-Id: Ia45d4a8893b0961534219bb96d9652719038c7a1

Change-Id: I97487bf353471bf9d245cd620780adfb1d3fc2b1

This patch adds bit account infrastructure to the bit reader API.
When configured with --enable-accounting, every bit reader API
function records the number of bits necessary to decoding a symbol.
Accounting symbol entries are collected in global accounting data
structure, that can be used to understand exactly where bits are
spent (http://aomanalyzer.org). The data structure is cleared and
reused each frame to reduce memory usage. When configured without
--enable-accounting, bit accounting does not incur any runtime
overhead.

All aom_read_xxx functions now have an additional string parameter
that specifies the symbol name. By default, the ACCT_STR macro is
used (which expands to __func__). For more precise accounting,
these should be replaced with more descriptive names.

Change-Id: Ia2e1343cb842c9391b12b77272587dfbe307a56d

Merge "Adds ability to measure with a higher precision the number of bits read per symbol." into nextgenv2

Change-Id: I371297e6ee000e6dc01ba1544763cbed429b0e5a

Currently the RD loop traverses 4X8 blocks in inverted N order while
the bitstream stores blocks smaller than 8x8 in Z order. This causes a
discrepancy where the RD loop reads uninitialized data while
performing intra prediction.  As a temporary fix simply disable the
use of the extended right edge for 4X8 blocks, until the bitstream can
be changed to match the logical structure of the blocks.

Change-Id: I44a9e4fc1a15cd551a7b38c3c1227bc5dac77e9a

Cherry-picked from aomedia/master: be029580

Change-Id: I3bab28488388f92f2db20e6af8fc9cf2d7f26015

From code only part of nextgenv2 (and not aomedia)

Change-Id: I21f7478a59d525dff23747efe5238ded16b743d2

While we are at it:
- Rename some variables to more meaningful names
- Reuse some common consts from a header instead of redefining them.

Cherry-picked from aomedia/master: 863b0499

Change-Id: Ida5de713156dc0126a27f90fdd36d29a398a3c88

- Change struct name to all caps SCAN_ORDER to be locally consistent.
- Rename struct pointers to 'scan_order' instead of hard to read short
  names 'so' and 'sc'.

Cherry-picked from aomedia/master: 30abc082

Change-Id: Ib9f0eefe28fa97d23d642b77d7dc8e5f8613177d

While we are at it:
- Rename some variables to more meaningful names
- Reuse some common consts from a header instead of redefining them.

Cherry-picked from aomedia/master: 09eea219

Change-Id: I61030e773137ae107d3bd43556c0d5bb26f9dbf8

In the header, all we need is number of stat types, not the names for actual
types.

Removing it avoids names like 'Y', 'U', 'V' and 'ALL' being visible
in all files that include the encoder.h header.

Change-Id: I874a73a3cfe6bcb29aedea102077a52addc49af6

- Const correctness
- Refactoring
- Make variables local when possible etc
- Remove -Wcast-qual to allow explicitly casting away const.

Cherry-picked from aomedia/master: c27fcccc
And then a number of more const correctness changes to make sure other
experiments build OK.

Change-Id: I77c18d99d21218fbdc9b186d7ed3792dc401a0a0

Move computing the segmentation_probs.tree_cdf table per symbol to
 computing it only when the probabilities are updated.

Change-Id: I3826418094bbaca4ded87de5ff04d4b27c85e35a

read per symbol.

Change-Id: I218abaa5172b769b66dba45050381c0212602668

This fixes mismatches due to overflowing low precision parameters.

Change-Id: If34e39ca7ab0adc9688d46b0e8ed62cbb6fdaff0

Change-Id: I1b41146ae844c985566f5f9fdaeb5d4a4a5927b6

Ransac's get_rand_indices originally used rand_r seeded with the
same value every time, producing the same random sequence at every
iteration. This causes the global motion parameters to be slightly
less accurate because ransac cannot improve the model fit after
the first attempt.

Change-Id: Idca2f88468ea21d19ba41ab66e5a2744ee33aade

Change-Id: If497816d7f6ee094d40872a2f988c91e90b78d7b

This function is called after `super_block_yrd` and assumes that the dst
buffer is correct but that is no longer always the case after
daf841b4 since we don't call
`txfm_rd_in_plane` after the RDO loop in `choose_tx_size_from_rd`.
We could fix this by always saving and restoring the dst buffer but
removing `rd_variance_adjustment` is a better solution:
- Getting the dst buffer always right is tricky as demonstrated by the
  fact that it is wrong now, even if we fix it now we could break it later
  and not notice
- Perceptual weighting is a good idea but `rd_variance_adjustment` is the
  wrong approach as it weights both the rate and the distortion:
  to get meaningful units you should only weight the distortion,
  weighting rate means that we pretend some bits cost less than other
  bits, this is not the case. The distortion weighting approach is
  implemented by Daala in `od_compute_dist` and we plan to experiment
  with this in AV1 too.
- Removing `rd_variance_adjustment` improves coding efficiency on all
  metrics, here are the results for objective-1-fast using the Low
  Latency settings:

      PSNR Y:     -0.14%
     PSNRHVS:     -0.17%
        SSIM:     -0.12%
      MSSSIM:     -0.12%
   CIEDE2000:     -0.07%

Change-Id: I74b26b568ee65f56521646b8f30dd53bcd29fce3

Experiment on coding block at resolution of 4x4 block.

Change-Id: I6aa201038f00c590747d800edb0a3e76ab1a51e8

Change-Id: Ibc73b4066dcdee45d32355144124762d26a16a28

This array was allocated and used to save and restore segmentation map,
however the original segmentation map was never modified between the
calls to save and restore.

Change-Id: Iaf0fbfed733c097e84cf44d2aa6b8f35d2fb456b

Change-Id: Ifcc329df240c0771172180933a6180b21fd31abe

This is not used since the commint 00cd5de5,
"Remove skip_recode speed feature".

Change-Id: Ic03da6c0095f6285a3889d5d22e8aaa2e6cbfd79

On average no compression performance changes. Encoding speed is
increased by 10~20% on some test clips in the derf set.

Change-Id: I9856caaa260303f6f6259686671bed7d51012277