opus - Mar 2011 - Crash bug in CELT plc

Hi all,

In my setup, I'm using a framesize of 320 samples at a sample rate of 
32000 Hz (10 ms frames). This gives me a mode where nbEBands is 21 and 
eBands[21] is 100 (the standard 2.5 ms short block ebands). This also 
gives me LM = 2, so what happens is eBands[nbEBands]<<LM is 400, whereas 
my framesize is only 320. This causes a stack overrun at line 1978 in 
celt.c in both calls to "renormalise_vector" and
"denormalise_bands". It
seems that the obvious solution for "denormalise_bands" is to call it 
with "st->mode->effEBands" instead of
"st->mode->nbEBands", but I don't
know what to do about the call to "renormalise_vector" (except perhaps
use "st->mode->effEBands" in the "for" loop as well,
but I'm not sure
that's the correct thing to do).

Cheers,
John Ridges

> Hi all,
>
> In my setup, I'm using a framesize of 320 samples at a sample rate of
> 32000 Hz (10 ms frames). This gives me a mode where nbEBands is 21 and
> eBands[21] is 100 (the standard 2.5 ms short block ebands). This also
> gives me LM = 2, so what happens is eBands[nbEBands]<<LM is 400,
whereas
> my framesize is only 320. This causes a stack overrun at line 1978 in
Actually, I think the "correct" thing to do is for mode setup to give 
you 160-sample shorts instead of 80-sample shorts (and thus LM will 
never be 2).