[Vorbis-dev] How to specify sample sizes?
giles at xiph.org
Sat May 21 01:05:34 PDT 2005
On Fri, May 20, 2005 at 08:22:10PM +0200, Nico Sabbi wrote:
> I want to explicitly specify the sample size, so, how can I do it?
These are generally referred to as "block sizes". They're in the vorbis
info header if you're curious what your files are using.
They can't be easily changed; doing so involves developing new modes for
> Can I set min_size == max_size?
> If so, is there any disadvantage? which ?
The idea is to use short blocks for impulsive sounds (percussion,
instrument 'attack's and so on) and longer blocks for tonal sounds.
Longer blocks are more efficient, but cause artefacts with sharp sounds,
so the best thing is to mix the two depending on the input audio. One
can of course produce valid vorbis streams where both block sizes are
the same, or where only one block size is actually used, but such
streams will generally be lower quality per bitrate.
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