[FFmpeg-devel] [PATCH] swscale-example: Don't test fast_bilinear.

Ramiro Polla ramiro.polla
Thu Aug 13 15:29:58 CEST 2009

On Wed, Aug 12, 2009 at 10:13 PM, Michael Niedermayer<michaelni at gmx.at> wrote:
> On Wed, Aug 12, 2009 at 09:47:06PM -0300, Ramiro Polla wrote:
>> Hi,
>> As michael suggested on a thread in -soc, fast_bilinear should not be
>> considered bitexact. This patch removes it from swscale-example.
>> Currently fast_bilinear reads past the end and its output is not
>> portable between architectures. Most of my attempts to make it more
>> bitexact made it not fast.
> i think it should still be tested, one just must keep in mind that the
> results are only compareable within C-C / MMX-MMX / MMX2-MMX2 ...

It's not only C-C / MMX-MMX... It always overreads one byte so the
output varies randomly. Fixing this would make a tiny little bit
slower (and you've already said no slower code for fast_bilinear).

And for regression testing swscale, swscale-example currently
generates 6.2Mb output. We can probably trim some data by printing
less chars, but it will still be in the many Mbs range. How do you
suggest we compare against a reference? bzip the output (should cut it
down to about ~250kb)? Or some other method besides swscale-example?


Ramiro Polla

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