[MPlayer-dev-eng] [PATCH] Preliminary musepack support

[Rich Felker]

On Tue, May 10, 2005 at 12:25:19PM +0200, Nico Sabbi wrote:
> Guillaume POIRIER wrote:
> 
> >Out of curiosity, is that supposed to be a trick to save as much bits
> >as possible, and rely as much as possible on the intelligence of the
> >demuxer/decoder ?
> >... or is that bad design?
> 
> everything that needs extradata is _very_bad_ design, imo.

Not at all. A custom dictionary/codebook can be INCREDIBLY useful for
improving compression efficiency, and it's easy to do with 2pass
encoding. These techniques are just underutilized by most common
codecs due to conflicting requirements (e.g. broadcast) or lack of
interest.

> Codecs can be made very simple and efficient, look at mpeg1/2/3 and to

Look at how poorly they compress...

> a lesser extend ac3 and aac with adts syntax. Unfortunately there's a 

AAC has extradata. There's just some stupid way for including it
repeatedly in the bitstream or using default values, either of which
wastes space. I forget which..

> real craze
> to use extradata that takes nothing good and overcomplicates demuxing 
> and decoding

It doesn't complicate things at all, unless you do stupid things like
making multiple packets of extradata...

Rich