[tremor] [Q]:if optimizing, where ?

[Julien Margetts]

I dont know much about Vorbis yet, but I beleive it (as most audio
compression standards) is based on modified discrete cosine transform or
MDCT time to frequency domain transform (for encode), and uses the inverse
transform IMDCT for decode.

These transforms are very processor intensive, and are already optimised in
the Tremor code, these filtering operations are definitely the ones to
target at the DSP though, along with other Windowing / filtering type
functions which might exist

Julien

PS: Thanks to all for the info on complexity. I think the general feeling
is: A bit more complex and a bit more RAM than MP3 in its current state, but
room for further optimisation.

PPS: MP3 on an ARM at 33MHz is possible with enough single cycle RAM ;)

----- Original Message -----
From: "42Bastian" <bastian42 at epost.de>
To: "Tremor" <tremor at xiph.org>
Sent: Tuesday, March 18, 2003 6:50 AM
Subject: [tremor] [Q]:if optimizing, where ?

<p>> Hi
>
> as I wrote in a different thread, I ported (well compiled) Tremor for
> the Atari Jaguar.
> Now I want to speed it up by doing certain parts with the additional
> DSP.
>
> Any hints on which parts I should first do in DSP are appreciated.
> Note: I only have 8KB for code and data in the DSP, so I surely can't
> port everything.

<p><p>--- >8 ----
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