[FFmpeg-devel] indeo4/indeo5 inverse quantization

Måns Rullgård mans
Mon May 31 01:37:55 CEST 2010

Maxim <max_pole at gmx.de> writes:

>> ((q >> 1) - (q & 1))
>> could be replaced by
>> ((q^1)-1)>>1
> What is the advantage of such a replacement? Anyway it looks more
> compactly and friendly to me...

The first form requires two registers for intermediate values on
some CPUs, whereas the second only needs one.

M?ns Rullg?rd
mans at mansr.com

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