Otherwise, the output can grow as large as SIG_SAT/(1-0.75), which can cause
an overflow when adding two values (before multiplying by the filter tap).

Reduces the XX values to avoid an overflow in silk_VQ_WMat_EC(), even in
floating-point.

Not observed yet (except when caused by a different bug), but "just in case"

Felicia Lim authored 8 years ago and Timothy B. Terriberry committed 8 years ago

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

When the energy is stable, we slightly bias energy quantization towards
the previous error to make the gain more stable (a constant offset is
better than fluctuations).

We reduce the bitrate by about 0.2% to 1% at low bitrate for the same quality.

Increasing the value at low rate seems to help a bit.

Otherwise, we risk having "temporal holes" in the HF that anti-collapse
can't always fill in.

It would trigger on the second frame of "S"s, causing holes in the spectrum

no dither