[MPlayer-dev-eng] container format

[Mark Zealey]

On Thu, Feb 06, 2003 at 06:06:01PM +0100, Michael Niedermayer wrote:

> > 2) Why does sz always have to be at least 1 character long - why cant it
> > just be a null?
> mpeg startcode emulation (if we allow 0 then there could be 0,0,1 which is a 
> startcode prefix in mpeg) perhaps we should drop the startcode emu thing, 
> dunno

And... seems like a waste of space to me.

> > 4) Possible use of compression on text, for example the headers (point 3)
> > and the subtitles.. The compression would be done on the whole text basis
> > and then maybe split up into the parts. Of course, the compression would
> > only be done where it was favourable...
> the headers are compressed, they surely could be compressed more but IMHO, its 
> not worth it, the 10k or so of repeated headers in a 600mb file dont really 
> matter, and the subtitles are considered as a normal stream like video so 
> they can be just encoded differently (invent a bzip2 based subtitle format 
> but thats idependant of the container ...)
> the info stuff like description needs some more thoughts, but i doubt that its 
> large enough for the extra comlexity to be worth it even if its repeated a 
> lot 

I meant the text headers in point 3 (Author:, Title: etc, this text block could
be unlimited size and in some situations it might save a bit of space... I could
see a lot of uses for this just text area, for example one could define a
Chapter: heading which would let the encoder encode the title, start, and end of
each chapter on the dvd into the heading so a player supporting the Chapter:
header could let the viewer skip straight through to a chapter.. just a thought

Headers we could have (as in ogg, multiple headers of the same name are allowed,
eg Author, to signify multiple authors)

Copyright - A copyright notice
Title - The title
Chapter - chapter info (start pos (frame?), end pos/length, title, whatever else)
Artist - for music
Track - for music again
TrackNumber - again
Genre - for both music and film
...

you get the idea, i like the flexability and the ability to extend at no cost..
also the ease of compression.

-- 

Mark Zealey (aka JALH on irc.oftc.net: #zealos and many more)
mark at zealos.org; mark at itsolve.co.uk

UL++++>$ G!>(GCM/GCS/GS/GM) dpu? s:-@ a17! C++++>$ P++++>+++++$ L+++>+++++$
!E---? W+++>$ !w--- r++ !t---?@ !X---?  !R- !tv b+ G+++ e>+++++ !h++* r!-- y