[vorbis-dev] Optimization and doubles vs. floats

[Timothy J. Wood]

>The mdct will be ok using floats. Don't know if all the rest of vorbis likes
>floats, though.

  Well, that is sort of what I'm wondering.  I don't want to have to take  
doubles as input to the MDCT, convert them to floats, do the operations,  
and convert back to doubles.  It sounds like I can just always use float,  
though (at least according to Taral).

>Which algo are you planning to use for the mdct? Oh, and Altivec is 128 bit,
>right?

  I'll probably start with what Takehiro Tominaga mailed out (haven't  
looked at it yet) or whatever ends up on the head of the repository.  Yeah,  
Altivec is 128 bit, so you can issue 4 floating point ops (including  
mult/add) per cycle, assuming you don't run out of memory bandwidth,  
completion slots, etc.

-tim

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