[FFmpeg-devel] [PATCH] avfilter/vsrc_mandelbrot: change sin to sinf for color computation

[Ganesh Ajjanagadde]

On Tue, Nov 24, 2015 at 2:28 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Tue, Nov 24, 2015 at 01:05:20PM -0500, Ganesh Ajjanagadde wrote:
>> lrintf is anyway used, suggesting we only care up to floating precision.
>> Rurthermore, there is a compat hack in avutil/libm for this function,
>> and it is used in avcodec/aacps_tablegen.h.
>>
>> This yields a non-negligible speedup. Sample benchmark:
>> x86-64, Haswell, GNU/Linux:
>>
>> old (draw_mandelbrot):
>> 274635709 decicycles in draw_mandelbrot,     256 runs,      0 skips
>> 300287046 decicycles in draw_mandelbrot,     512 runs,      0 skips
>> 371819935 decicycles in draw_mandelbrot,    1024 runs,      0 skips
>> 336663765 decicycles in draw_mandelbrot,    2048 runs,      0 skips
>> 581851016 decicycles in draw_mandelbrot,    4096 runs,      0 skips
>>
>> new (draw_mandelbrot):
>> 269882717 decicycles in draw_mandelbrot,     256 runs,      0 skips
>> 296359285 decicycles in draw_mandelbrot,     512 runs,      0 skips
>> 370076599 decicycles in draw_mandelbrot,    1024 runs,      0 skips
>> 331478354 decicycles in draw_mandelbrot,    2048 runs,      0 skips
>> 571904318 decicycles in draw_mandelbrot,    4096 runs,      0 skips
>>
>> Signed-off-by: Ganesh Ajjanagadde <gajjanagadde at gmail.com>
>> ---
>>  libavfilter/vsrc_mandelbrot.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> LGTM
>
> thx

pushed, thanks.

>
> [...]
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