[FFmpeg-devel] [PATCH] Optimize QTRLE encoding

Alexis Ballier alexis.ballier at gmail.com
Thu Feb 14 18:35:23 CET 2013

2013/2/12 Malcolm Bechard <malcolm.bechard at gmail.com>:
> I don't think we can assume all compilers will optimize that. The fact that
> this code runs 2x-3x faster when compiled with VS2010 vs. gcc shows how
> much optimization can be missed (although I'm hoping it's something I'm
> doing wrong with the gcc compile).
> The goal of the patch is to speed up that loop so while it may be a small
> or even immeasurable speedup I think it's valid portion of the work without
> adding any complexity to the code.

I was only asking if you _did_ see an improvement with that change
alone; you should still probably submit two patches: a first one for
this change alone, and a second one for the algorithm change.

btw I'm not sure how you compile this code, the 2x-3x difference seems
huge, if you compile with ffmpeg build system it should be done
automatically but if you compile by hand be sure to use gcc -O2 so
that it optimizes it.

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