This patch sets up a quad_tree structure (pc_tree) for holding all of
pick_mode_context data we use at any square block size during encoding
or picking modes.  That includes contexts for 2 horizontal and 2 vertical
splits, one none, and pointers to 4 sub pc_tree nodes corresponding
to split.  It also includes a pointer to the current chosen partitioning.

This replaces code that held an index for every level in the pick
modes array including:  sb_index, mb_index,
b_index, ab_index.

These were used as stateful indexes that pointed to the current pick mode
contexts you had at each level stored in the following arrays

array ab4x4_context[][][],
sb8x4_context[][][], sb4x8_context[][][], sb8x8_context[][][],
sb8x16_context[][][], sb16x8_context[][][], mb_context[][], sb32x16[][],
sb16x32[],  sb32_context[], sb32x64_context[], sb64x32_context[],
sb64_context

and the partitioning that had been stored in the following:
b_partitioning, mb_partitioning, sb_partitioning, and sb64_partitioning.

Prior to this patch before doing an encode you had to set the appropriate
index for your block size ( switch statement),  update it ( up to 3
lookups for the index array value) and then make your call into a recursive
function at which point you'd have to call get_context which then
had to do a switch statement based on the blocksize,  and then up to 3
lookups based upon the block size to find the context to use.

With the new code the context for the block size is passed around directly
avoiding the extraneous switch statements and multi dimensional array
look ups that were listed above.   At any level in the search all of the
contexts are local to the pc_tree you are working on (in?).

In addition in most places code that used to call sub functions and
then check if the block size was 4x4 and index was > 0 and return
now don't preferring instead to call the right none function on the inside.



Change-Id: I06e39318269d9af2ce37961b3f95e181b57f5ed9

Change-Id: Ibf360fe0728e07de448e77e3841c49eb25d3ba2d

This commit compares the current original frame to the previous
original frame at 64x64 block level and decides if the entire
block belongs to background area. If it is in the background area,
skip non-RD partition search and copy the partition types of the
collocated block in the previous frame.

For vidyo1 in the rtc set, this makes the speed -5 coding speed
about 8% faster. The overall compression performance is down by
1.37% for rtc set.

Change-Id: Iccf920562fcc88f21d377fb6a44c547c8689b7ea

This commit added a check of reference frame to make sure that pre
buffer pointers are initialized only when necessary and make them
to 0 if ref frame is intra, hence those buffer should never be used.

Change-Id: Ieb474fcd9feb759f02e2f9c282b7348a8fa31117

Delete code relating to the old VP8_TUNE_SSIM flag
as this code does not currently work and is largely made
redundant in VP9 by the various AQ modes.

Change-Id: I71f28e1f680573d296422254489000678552b17b

Remove duplicate rd_thresh code introduced when vp9_rd_pick_inter_mode_sub8x8()
was forked from vp9_rd_pick_inter_mode_sb().

Change-Id: I3c9b7143d182e1f28b29c16518eaca81dc2ecfed

Fix rate control bug whereby the rate factor heuristics
were being updated on arf overlays causing a rate surge
for a few frames followed by a corrective drop.

This fix eliminates many of the overshoot problems that
we were seeing on hard clips (even without applying
stricter vbr rate control) and also helps quality on
almost all clips with some hard clips improving by >5%.

Overall quality results measured at speed 2.
Derf  +1.78% opsnr , +2.44% SSIM
Stdhd +2.41% opsnr, +2.85% SSIM

Change-Id: I2369df6295c2705963fa6307877f6acb304bcc39

Just to be consistent with min_frame_bandwidth & max_frame_bandwidth names.

Change-Id: I36702c708cba9ad1a5c36393f37758a2edeadb90

Change-Id: If6f013835b69ae61b0a0c6006fe0955303f579a5

Change-Id: I87819fed5aebb6ffe2f4d4655df226235a3d21cb

Change-Id: I988eea8f78f71135b914661420c5c75674e5c010

Fix return values for webm_read_frame so that we can distinguish between
error and end of stream. 0 - Success, 1 - End of stream, -1 error.

Change-Id: Ic35d0c7d7a166e027711a3d2300ecdda25a5d0cc

Change-Id: Ib8c1b3b0a5a5689d3261dc822a69e9d473b89be1

Change-Id: Id156af5662ebe6fbe1cab636564f5f4bedb85ab0

Change-Id: Id687aa617650a859463e7ae63dd4c0dc4f3e4779

Change-Id: I5ed360585dae2c9fea6c32058dbfb8ec07700677