[Matroska-devel] EBML specification component for review - Element ID

Jerome Martinez jerome at mediaarea.net
Thu Apr 30 21:56:27 CEST 2015

Le 30/04/2015 21:00, Erik Piil a écrit :
> The EBML element ID is encoded as a variable size integer with, by 
> default, widths up to 4. Another maximum width value can be set by 
> setting another value to EBMLMaxIDWidth in the EBML header. See 
> section 5.1. IDs are always encoded in their shortest form, e.g. 1 is 
> always encoded as 0x81 and never as 0x4001. This limits the number of 
> IDs in every class with the number of IDs in the previous classes. 
> Furthermore, values with all data bits set to 1 and all data bits set 
> to 0 are reserved, hence the effective number of IDs are as follows 
> for different widths. Note that the shortest encoding form for 127 is 
> 0x407f since 0x7f is reserved.

Maybe I miss something, but I don't catch the need of classes, which are 
used nowhere else in the spec.
I would remove any reference to classes.

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