[CELT-dev] CELT grabbing 100KB of memory right off the top

Jean-Marc Valin jmvalin at jmvalin.ca
Tue Apr 19 03:17:08 PDT 2011

On 11-04-19 01:35 AM, Andrew Lentvorski wrote:
>> Lowering the "complexity setting"
>> CELT_SET_COMPLEXITY should definitely help at the expense of lowering
>> quality. I suggest trying complexity 4, which disables the pitch search
>> for the prefilter.
> I see no visible change moving from 5 to 4. Even moving the whole way to
> 0 only gains about 10% (3.46ms per loop vs. 3.14ms per loop)

Right, because the post-filter must be disabled already. So I recommend 
keeping the default and not touching anything for that one (the quality 
drop is probably not worth the lower CPU).

>>> I already did a quick profile of the fixed point encoder and it wasn't
>>> doing anything obviously stupid. There were 4 hotspots at 15%, 8%, 7%,
>>> and 5% respectively. The 15% involved ilog.
>> ilog is an easy one. Most platforms have a hardware instruction to
>> compute that, so just using it should make that 15% go away.
> Yeah, that was straightforward to buy almost 10%.

Good :-)


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