[CELT-dev] Issue with signals with lots of bass

[Jean-Marc Valin]

Hi,

We've just found an issue when encoding signals that have very powerful
bass (e.g. a loud 40 Hz tone). Turns out that was a combination of the
MDCT leakage with some inefficiency in the VQ search. There's a
tentative fix for that in git, which I'm encouraging everyone to test.
To enable the fix, look for these lines in alg_quant() (vq.c):

#if 0
   if (K > (N>>1))

Just replace with #if 1 and the fix will be enabled. I'm not yet 100%
sure it's safe, so please report and problem (or success). The good
thing is that this should not only solve the original, but it should
also reduce the CPU usage.

Cheers,

	Jean-Marc