[ogg-dev] Ogg/Kate preliminary documentation

Ivo Emanuel Gonçalves justivo at gmail.com
Wed Jan 16 06:32:41 PST 2008

On 1/16/08, ogg.k.ogg.k at googlemail.com <ogg.k.ogg.k at googlemail.com> wrote:
> Also, it'd likely take a rewrite of oggmerge to make it
> usable for multiplexed streams, I think it assumes a single logical stream
> per physical stream, though I didn't have an in-depth look at this issue.

You are likely correct.

> I did see references to Skeleton, I'll have a look at it. I didn't
> realize it was used widely

It's not widely used currently.  The idea is to make that happen.

> As for .ogv for Theora, do you mean Theora-in-ogg, or raw Theora ?
> If Theora-in-ogg, then what about Theora multiplexed with other stream
> types, like Vorbis, since a lot of videos will have sound embedded ?

.ogv is the file extension for video on Ogg.  That is usually Theora,
but even OggMNG is supposed to use it.  And of course this also counts
if the file has multiplexed audio.  For instance, the basic media file
Theora + Vorbis + Kate/CMML (+Skeleton) would use .ogv.  People give
too much meaning to file extensions and we have to rely on that and
give them what they want, which is a way to distinguish  music from
video right from the file extension.

> I do know, however, that people in eastern countries tend
> to dislike utf-8 for the size it takes for their language, as it's been,
> /optimized/ for the latin alphabet. I am also not clear if every code point
> can be coded in utf-8, I'll have to dig that up.

As far as I know, only the Japanese dislike UTF-8, and that's related
to how their language's characters were ordered in the Unicode table
(rather randomly).  UTF-8 is really the only sane way to support all
world's languages.  UTF-16 is considered by many to be overkill and no
better solution has ever been made.

> Yes, this is a fair point, but then you have Vorbis, Speex, and FLAC,
> each with its own particularities.

It's not really the same thing.  Each of those formats serves a niche.
 Roughly: Vorbis for lossy music, Speex for VoIP, and FLAC for

CMML does of course other things besides subtitles.  Subtitle support
was pretty much just added recently.  Kate however does not seem to
offer more than CMML in the lyrics/subtitles department, besides
perhaps the concept of converting other subtitles formats (ASS, SRT,
etc) to Kate which is a tool concept, not a format concept.  So CMML
and Kate end up both serving the same niche.

This does not mean Kate development should stop.  It just means that
if you are not willing to join efforts with the other developers we
will end up with two (let's not count Writ) different formats for the
same niche.  And then we have to tell people which of them should be
the default format for subtitles and lyrics, which means one format
will lose in favor of another, frustrating its developer(s).  I don't
think anyone wants that.


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