commit b9370acd43ec6f9a2429b13d4e5d9c1ca44e8cef
author Debargha Mukherjee <debargha@google.com> Thu Mar 23 06:10:18 2017 -0700
committer Debargha Mukherjee <debargha@google.com> Thu Mar 23 21:55:00 2017 +0000
tree 97073fa6fda6453900ea7dff7e67f35b18f631b3
parent 561d0af0e39037fdebc2487214d790978ad7f0b4

Simplify warped motion estimation to use 2d ls

Use a simpler warped motion estimation scheme that uses a 2d
least squares problem, where the underlying assumption
applied is that the motion vector computed at the center
of the current block using the warp model is exactly the same
as the motion vector transmitted for the block.

The main motivation is to reduce the complexity of the
estimation process.

Coding efficiency drop is about +0.25% on lowres:
-1.152% (from -1.396%).

Also, removes code for non-approximate division and bakes
approximate divison in.

Change-Id: Ie4ad8e32593b09f7e1920c70b0b92545236ddc54