[FFmpeg-devel] [PATCH]levc/hevc_cabac Optimise ff_hevc_hls_residual_coding (especially ARM)
Carl Eugen Hoyos
cehoyos at ag.or.at
Tue Jan 19 16:59:39 CET 2016
John Cox <jc <at> kynesim.co.uk> writes:
> >> +#define UNCHECKED_BITSTREAM_READER 1
> >I don't think that's right, and is a security issue.
> I added that line as (nearly) every other decoder in
> liavcodec has it -
> in particular h264_cabac.c has it.
Extensive testing was done before it was added.
Could you confirm how much of the speedup comes
only from this change?
While we definitely all welcome a noticeable speedup
of hevc decoding (and while my opinion on your patch
has limited relevance) I believe that the patch
absolutely has to be split: First step would be to
have a split between changes in the general code and
changes to arm assembly, I believe the first patch
then may be split further.
I am a little surprised that you wrote some asm
functions that are slower than what the compiler
produces: Did you analyze this?
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