ogg dev - Feb 2008 - OggPCM: support for little-endianness only?

Jean-Marc Valin wrote:
> I'd be quite interested if you could provide a benchmark that really
> shows by swapping to make a difference.
Yes, I agree that the speed difference between the swapping and the
no-swapping case is negligible, but I'm talking about CPU cycles.

With libsndfile people do stream 10, 20 or more channels of audio
off disk at once, with soft realtime requirements. In situations
like this, avoiding the CPU cycles of end swapping is probably a
good idea.

Erik
-- 
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Erik de Castro Lopo
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"You can have quality software, or you can have pointer arithmetic;
but you cannot have both at the same time." -- Bertrand Meyer, 1989

Erik de Castro Lopo wrote:
> Jean-Marc Valin wrote:
> 
>> I'd be quite interested if you could provide a benchmark that
really
>> shows by swapping to make a difference.
> 
> Yes, I agree that the speed difference between the swapping and the
> no-swapping case is negligible, but I'm talking about CPU cycles.
> 
> With libsndfile people do stream 10, 20 or more channels of audio
> off disk at once, with soft realtime requirements. In situations
> like this, avoiding the CPU cycles of end swapping is probably a
> good idea.
> 
This is all well and good but OggPCM is in an Ogg transport
stream, so that needs to be unpacked anyway.

-- 
imalone

Ian Malone wrote:
> This is all well and good but OggPCM is in an Ogg transport
> stream, so that needs to be unpacked anyway.
Fair enough. Since the ogg pages (which I beleive are 4k) need
to be unpacked anyway, there is little harm in having to 
(possibly) do endswapping as well.

Erik
-- 
-----------------------------------------------------------------
Erik de Castro Lopo
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"Yeah, all that emacs is missing to be counted as a full-featured
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