[Vorbis-dev] Controlling the vorbis encoder precisely

[xiphmont at xiph.org]

On Nov 23, 2007 5:23 AM, Robin Siegemund
<r.siegemund at digitalpublishing.de> wrote:

> The problem is the sample-exact separation between those encoded wave
> sounds: If I add the audio data from a new wave sound to the encoding
> process the resulting vorbis packets also include some samples from the
> previous encoded wave file at the beginning.
>
> This seems to be caused by the vorbis encoder using a "delay window" (or
> something like that) during the process so there's always some data left in
> the current encoding state.

It is not using a delay window, it is using a lapped transform space.
Any audio output from the encoder is the product of overlapping the
inverse transform of two audio packets due to the way the MDCT works.

You'll either need to pad the samples or use completely seperate
chained streams.

Monty