[FFmpeg-devel] [PATCH 1/4] zmbvenc: don't sum the entropy when blocks are equal

Matthew Fearnley matthew.w.fearnley at gmail.com
Thu Dec 20 19:46:02 EET 2018

On Thu, 20 Dec 2018 at 16:30, Tomas Härdin <tjoppen at acc.umu.se> wrote:

> I have a feeling this could be sped up further by just doing *xored =
> histogram[0] == ZMBV_BLOCK*ZMBV_BLOCK after the loops, if [PATCH 3/4]
> is applied before this. Computing both histogram and xored in the loop
> seems pointless.

You're right, that speedup didn't occur to me.  It makes the logic a bit
more tenuous, but it would be more efficient.
Note that bw,bh aren't guaranteed to equal ZMBV_BLOCK, so `histogram[0] ==
bw*bh` would have to be used to guard against those (literal) edge cases.

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