[Ffmpeg-devel] MMX/MMX2 and SSE optimizations for H.264 decoding
Thu Sep 22 22:23:58 CEST 2005
On Thu, Sep 22, 2005 at 10:47:51AM -0700, Loren Merritt wrote:
> On Thu, 22 Sep 2005, Romain Dolbeau wrote:
> >Loren Merritt wrote:
> >>we have:
> >>we do not have equivalents of:
> >The additional question is, are we going to be bitten by
> >Amdahl's Law ? i.e. are these important enought during
> >the decoding process to justify optimizing them ?
> idct is not so important (iirc 3% total speedup when I mmxed it).
> qpel_4 matters only on videos that use 4x4 motion partitions.
> qpel_8 and loop_filter are important.
And maybe the current code should be fixed before it gets optimized. I get
massive artifacts with AltiVec-enabled H.264. I'll post details shortly.
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