[vlc-devel] [PATCH 2/2] Android: disable speex

[Rémi Denis-Courmont]

On Thu, 2 Feb 2012 21:29:05 +0100, XilasZ <xilasz at gmail.com> wrote:
> Ah yeah, i forgot, sorry.
> 
> What's wrong exactly ? it is done that way in ugly.c.

The ugly resampling algorithm is nearest neighbor. Nearest neighbor is
identity if the input and output rate are equal. So it can safely be
skipped when not resampling. However, the ugly resampler is obviously
subject to aliasing.

With SRC or speex, the resampling function is always called to avoid noise
when the resampling starts or stops. That does not necessarily mean that
those resamplers are slow (nor fast) when the input and output rate are
equal.

> How can it produces annoying noises, when nothing is done ?

The problem occurs when the input rate changes, especially when it changes
from same-as-output to not-the-same-as-output or vice versa.

-- 
Rémi Denis-Courmont
http://www.remlab.net/