tree 2d369557a61f59bc4e9e9c76dfd9fdf09859adb8
parent ad2c178236e1fc553629eded5b901d72b7cf6e05
author Alexander Bokov <alexanderbokov@google.com> 1508283706 -0700
committer Yaowu Xu <yaowu@google.com> 1511053354 +0000

Add extra hashing mechanism on the TX size search level

In TX size search the rate and distortion values are often computed for
residuals that have already been seen before, with exactly the same
entropy context. Such repeated computations occur when the residue
signal is the same for 2 or more partitions for a given prediction mode.
By saving previous RD search results we can achieve some encoder
speed-up at the cost of higher RAM consumption (~20MB).

Test results with all default experiments:
Speedup      15% (measured on 4 lowres 30-frame sequences)
compression   0%

Change-Id: I8d9b8dd483cf862f0864b50ae80466beac978290