tree ab224708bee244775e81d64ba8a93ad70c8d748e
parent 6d461a343105ac04fce4f25fb5285a1013b29359
author Salome Thirot <salome.thirot@arm.com> 1682701365 +0100
committer James Zern <jzern@google.com> 1683167063 +0000

Specialize Neon masked sub-pixel variance by filter value

Use the same specialization as for the other sub-pixel variance
functions. The rationale for the specialization is as follows:

The optimal implementation of the bilinear interpolation depends on the
filter values being used. For both horizontal and vertical interpolation
this can simplify to just taking the source values, or averaging the
source and reference values - which can be computed more easily than a
bilinear interpolation with arbitrary filter values.

This patch introduces tests to find the most optimal bilinear
interpolation implementation based on the filter values being used.
This new specialization is only used for larger block sizes.

Change-Id: I1c59e31bee9a14059baa9938cc0dc9bc91e9bef4