[vorbis-dev] Tarkin at last

Gregory Maxwell greg at linuxpower.cx
Thu Jan 4 15:53:58 PST 2001

On Fri, Jan 05, 2001 at 12:40:21AM +0100, Lourens Veen wrote:
> I need to read up on zero-tree packing, unless someone could give an
> short explanation here?

The easiest way to do wavelet image compression is to just throw out all
coeffs smaller then a certian threshold. This works supprisingly well.

So much so that you typically end up having to spend more bits saying where
the remaining coeffs go then actally saying them. 

You can view a wavelet transformed image as a pyrmid, build a tree from the
'base' saying weither the layer below it has any non-zero coefficents. After
making this map, you transfer the remaining coeffs.

I have doubts if this method is useful is a super-high-loss 3d video
compressor. A simmalr approach can be accomlished with vector code words.

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