Re: Re: hdot264 - Developer

	Re,

On Wed, 2003-07-09 at 14:41, Aitor Garay wrote:
> Hi there!,
> 
> > indeed, i'm playing with ref software in order to get a grasp of
> > H264 capabilities. And i must admit H264 is by far more complex
> > than i first thought.
> 
>     What impressions did you get while playing with the reference
> software?  

	it is a mess, most probably as a result of
	collaborative code aggregation. Informations are
	duplicated, redundant, all over the place, etc...
	(There must be at least 3  ways in there to guess whether 
	a macroblock is intra or not :)
	*But* it matches rather well the norm, which is rather
	lucky. And it's hence useful. For instance, look at the
	specs regarding loop-filtering: hard to decipher, ain't it?
	But when you look at the code (loopFilter.c), it appears
	far simpler and straightforward. And you can then play
	with, replacing it by some code of your own.
	This is the main strength of the ref software, i think.

Do you think it's worth on using it as a base for developing
> a new codec, 

	forget about it :)

or it's better to start a new clean implementation?
> 
	definitely. But keeping the ref software as
	a test-bed for experimentations on isolated
	new code, before it's incorporated in the
	rest, would prove helpful.

>     Encoding is even more depressing,   Some sources suggest that
> H.264/AVC encoding requires roughly 8 times more encoding processing
> power than MPEG-2.  Other sources say that it's only 4-5 more
> complex.  There is a big difference between both estimations!

	the ref software is not a good source for reliable figures
	about encoding time ;) But judging from the complexity at
	stake, what you quote wouldn't surprise me at all.


	bye!
		Skal






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