commit 790fb132157aab73b20c94a223dbe4470036d832
author Ronald S. Bultje <rbultje@google.com> Tue Mar 26 16:46:09 2013 -0700
committer Ronald S. Bultje <rbultje@google.com> Tue Mar 26 16:46:09 2013 -0700
tree 3b12459d77a97373b4e4c9240a4d135a4ef874f5
parent 646616602dca641f8fe38ca4c7adbb77df5ae8e3

Use above/left (instead of previous in scan-order) as token context.

Pearson correlation for above or left is significantly higher than for
previous-in-scan-order (absolute values depend on position in scan, but
in general, we gain about 0.1-0.2 by using either above or left; using
both basically just makes this even better). For eob branch skipping,
we continue to use the previous token in scan order.

This helps about 0.9% on derf after re-training on a limited data set.
Full re-training and results on larger-resolution clips are pending.

Note that this commit breaks trellis, so we can probably get further
gains out of it by fixing trellis at some later point.

Change-Id: Iead68e296fc3a105cca746b5e3da9555d6010cfe