[Vorbis-dev] Re: Streams with block sizes 4096 and 8192

[Michael Smith]

> >
> >If we did remove 8196 (and I'm not saying we would), we _certainly_
> >wouldn't even consider removing 4096 - that's in wide use, and has
> >been for some years. Removing it would break a lot of files that users
> >are happily playing at the moment.
> >
> 
> But I think, in stereo, if 4096 block size supportted, another 3K words(32 bits/word) for workbuffer
> and another 2K words(32 bits/word or 16 bits/word) for window table, it is a not acceptted in portable
> audio player. then, I also suggest not supportting 4096 and 8192 block sizes.

As Monty and I said, block size 4096 is used by most encoders (though
only at some bitrates) for cd-rate audio. So removing that is not
acceptable for vorbis-compliant decoders.

Monty noted that 8192 is only useful for high-sampling-rate audio
(such as 96kHz material), and it's reasonable for a portable device to
not support those files. So a portable could omit the 8192 size.

We're thinking about defining a "portable profile" that limits various
aspects of the vorbis specification. That 8192 block size would be one
of the things that wouldn't be required in such a profile, but 4096
would still be required.

Mike