[Matroska-devel] Re: DRAFT: new elements for compression/encryption

Steve Lhomme steve.lhomme at free.fr
Fri Oct 17 10:00:27 CEST 2003


Pamel wrote:

>>* KaxContentEncodingScope: Tell whether the frame contents, the track's
>>private data or both have been modified in this way.
>>0 - only the frame contents
>>1 - only the track's private data
>>2 - both
>>Default value is 0.
> 
> 
> I like that, its clever.  I can imagine that people would just start using one
> all of the time, but this saves us the trouble of deciding which that would be.

How about the "only certain frames" ? That would also encryption of only 
some parts of a movie or 1 frame every 3, so that the user still need to 
get a way do decrypt it and still be somehow playable. It would also 
save some encryption time on some systems.
I propose a bitfield for these values :
bit 0 : track's private data
bit 1 : frames marked as such (we need to use something in the frame, 
probably a bit in the frame header)
bit 2 : all frames

I was thinking about adding a Bitfield EBML type someday. Maybe we could 
do it now.





More information about the Matroska-devel mailing list