Warp wrote:
> Invisible <voi### [at] devnull> wrote:
>> JPEG compression works by decomposing an image into a set of (2D) cosine 
>> waves, and then quantinising the data. In my opinion, cosines are not 
>> actually a particularly good choice for this. (Gibb's phenominon is very 
>> ugly to look at.) So I'd like to try it with other functions - but first 
>> I need to work out how...
> 
>   So you are going to reinvent JPEG2000 then?-)

Nah. JPEG2000 uses wavelets - a technology I have repeatedly failed to 
comprehend. I'm just using a decomposition with a different set of basis 
functions. ;-)

[We casually overlook the fact that JPEG doesn't work in the RGB colour 
space, it works in some weird custom space to better accomodate the 
peculiarities of the human eye. There's also several layers of plain 
ordinary lossless compression happening in addition to the lossy DCT 
quantinisation step. And... basically JPEG is complicated. I'm only 
trying to frobnicate one tiny step in the process.]

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