[Matroska-devel] EBML

[Steve Lhomme]

Martin Nilsson wrote:

> Steve,

Hi Martin,

> Note that the draft I linked to is much more developed than the one I 
> sent you. The major things left to do is textual descriptions of my DTD 
> suggestion, the value restriction property and listing the EBML standard 
> elements. I hope to be able to do that tonight. I also intend to write 
> an EBML DTD for XHTML to see that the DTD language is expressive enough 
> to handle XML (and write an XHTML to EBML converter in the process). 
> Once that is done my EBML specification is ready for publication. 
> However, the question is if it is anywhere near what you want :)

Well, I'll first have to look at your work to see if there is no 
mistake/misunderstanding. Otherwise it will be very valuable to us ! It 
looks like a RFC and could be used for other things. A formal 
description is for sure something that will help people understanding it.

> I have a question right away though. Are there any secret rules for EBML 
> element ID assignment, or is it just taking whatever number you feel like?

In the case of Matroska we used 4-octets long IDs for elements that be 
used as damaged file recovery (syncword). Otherwise it just depends on 
the occurence and the importance of the ID (more often is a short one to 
reduce the overall size of the file).