[vorbis-dev] vorbis on playstation 2

[David Etherton]

> > 44% mdct_backward
> > 10% _vorbis_apply_window
> > 9% vorbis_book_decodevv_add
>
> This is obviously cache kill.  Note that the mdct itself is not the
> only culprit of that, of course.

Interesting.  I turned on _LOW_ACCURACY_ and rebuilt the library and the
total cycle count for my test case went from 950M cycles to 723M cycles.
The two sincos lookup tables are 4K each in "full" mode which are likely
going to thrash the cache.

I could move the whole LUT into scratchpad easily enough (some of our
low-precision character animation uses a small lut in scratchpad already, it
was a pretty good win) although I'd like to trim the table down a bit.
Would I be better off going to a signed short to cut the table size in half
or just cut the number of entries in half?

Thanks,

-Dave

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.