[theora-dev] newest cvs and mplayer

David Kuehling dvdkhlng at gmx.de
Fri Jun 6 10:43:32 PDT 2003

>>>>> "Ralph" == Ralph Giles <giles at xiph.org> writes:

> the header packets all begin with 0x8*, 'theora'. That is, the first
> bit is '1' for non-data packets. 0x80 is the first header, 0x81 are
> the comments and 0x82 are the decoder tables. Data packets begin with
> the bit '0'.

thanks for the info.  

> There's a hack with the granulepos to assist seeking; the granulepos
> is really a fixed point number, with the integer part counting
> keyframes and the fractional part counting frames since the last
> keyframe.  Therefore you can look for the lower-order bits being zero
> to identify a keyframe. The radix is variable from file to file
> however, you'll have to pull it out of the header to be reliable.

i know, my heuristic currently is `!(granulepos&0x1FF)' :-)  


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