[Ffmpeg-devel] ffmpeg now 2x slower: sse16 vs nsse16
Thu Nov 10 02:31:18 CET 2005
I recently updated my copy of ffmpeg with the latest CVS release from the
February version I had previously been using and found that with the same
settings it is now twice as slow to encode!
Doing a profile of the two versions I found that with the latest version 47%
of the time was spent in nsse16_mmx.
In the previous version nsse16_mmx doesn't seem to have run at all.
In the previous version sse16_mmx took 4% and in the latest version it was
replaced by sse16_sse2 which took 1.6%
Any ideas as to what has changed over the last few months that could have
In both cases I had:
m_codec_context->me_sub_cmp = FF_CMP_NSSE;
m_codec_context->mb_cmp = FF_CMP_NSSE;
m_codec_context->nsse_weight = 0;
m_codec_context->mb_decision = FF_MB_DECISION_SIMPLE;
I'm using a P4 with Hyperthreading.
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