[FFmpeg-devel] [PATCH] ra144enc: fix use of scalarprod_int16

Christophe Gisquet christophe.gisquet at gmail.com
Wed Mar 5 21:50:35 CET 2014


2014-03-05 19:51 GMT+01:00 James Almer <jamrial at gmail.com>:
> This doesn't appear to have fixed the problem.

I guess Michael's addition is the one not working?

> Adding
> %if mmsize == 8
>     emms
> %endif
> at the end of scalarproduct_int16 in dsputil.c like it's done in other files
> however worked for me.

The issue here is that emms might be emitted quite frequently, which I
believe was Michael's reason to do this. I have just verified he is
right: the ssse3 version takes ~155 cycles, and adding unconditionally
emms brings it to 185.

Anyway, this is weird. At this point, I think this is causing more
headaches than encoding with such a codec is worth.

I'd suggest reverting the change altogether, because adding emms to
the dsp is probably more detrimental.


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