[MPlayer-cvslog] CVS: main/DOCS/tech mpcf.txt,1.75,1.76

[Michael Niedermayer]

Hi

On Sat, Sep 17, 2005 at 04:15:49PM -0400, Rich Felker wrote:
> On Sat, Sep 17, 2005 at 09:27:41PM +0200, Michael Niedermayer CVS wrote:
> > +back_ptr
> > +	pointer to the latest syncpoint, for which there is at least one
> > +	keyframe prior to the global_timestamp in every stream
> > +
> 
> This encoding is inefficient and will often make back_ptr 1 byte
> larger than it needs to be. Instead, we should have:
> 
> actual_back_ptr == coded_back_ptr*8+7+9
> 
> The first *8 and +7 are because startcodes are 8 bytes long, so as
> long as we point to a position no more than 7 bytes before the
> syncpoint we want, we can be guaranteed to find the syncpoint with a
> trivial 15-byte linear search. The final +9 is because the minimal
> possible distance back to the previous syncpoint is 9 (8 byte
> startcode + 1 byte framecode immediately following it).

hmm, i am not against this, feel free to commit such a change

[...]

-- 
Michael