[ogg-dev] OggPCM2 : chunked vs interleaved data

Erik de Castro Lopo
Tue, 15 Nov 2005 15:49:37 -0000

Sampo Syreeni wrote:

> Secondly, I'd like to see the channel map fleshed out in more detail.

Sampo, I'm the one who came up with the channel mapping this.

Let me flesh it out a bit more this evening.

> (As a further idea prompted by ambisonic compatibility encodings, I'd
> also like to explore the possibility of multiple tagging. For example,
> Dolby Surround, Circle Surround, Logic 7 and ambisonic BHJ are all
> designed to be stereo compatible so that a legacy decoder can play them
> as-is. But if they are tagged as something besides normal stereo, such a
> decoder will probably just ignore them. So, there's a case to be made
> for overlapping, preferential tags, one telling the decoder that the
> data *can* be played as stereo, another one telling that it *should* be
> interpreted as, say, BHJ, and so on. Object minded folks can think of
> this as type inheritance of a kind. But of course this is more
> food-for-thought than must-have-feature since nobody else is doing
> anything of the sort at the moment.)

Doesn't the Channel Conversion Header fulfil this need? Maybe
it needs a bit more explanation and an example.

> > Anyone wants to speak in support of chunked PCM?
>
> Actually I'd like to add a general point against it.

Thanks for speaking up. Opinion noted.

Erik
--
+-----------------------------------------------------------+
  Erik de Castro Lopo
+-----------------------------------------------------------+
A Microsoft Certified System Engineer is to computing what a
MacDonalds Certified Food Specialist is to fine cuisine.