[gdal-dev] Kakadu library and Component transform with GDAL

[Dimitri Sarafinof]

Dimitri Sarafinof wrote:
> Hello,
> 
>  
> 
> I'm working in the French National Geographic Institute on a project for 
> the French Ministry of Defence. The goal is to encode imagery in JPEG
2000.
> 
> We're working with Kakadu library v6 (we've got a Commercial Enterprise 
> licence) and there's no option to use the components transform (in 
> particular ICT) when it's linked to GDAL. This option seems to be very 
> useful to compress RGB imagery and have better quality. It's recommended 
> to use it for RGB data but we can't do it with GDAL. So we would to know 
> if this option is going to be implemented next wit

Dimitri,

Are you talking about encoding the actual image in a different color space,
like YCbCr?  I have no plans to implement this but I would certainly be
open to incorporating a patch that does this if you could come up with one.

Best regards,
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Franck,

I'm talking about encoding an RGB image with a multiple component transform
which is described in JPEG 2000 specification (ISO 15444-1, Annexe G.2 and
G.3). This is a decorrelating transformation applied to the first three
components of an image...it's not really a color space change because JPEG
2000 data are displaying in RGB. 
That can be made with the Kakadu binaries (option "CyccC=yes" with
Kdu_compress). We've also seen that it was automatically used with ECWJP2
library but not with the JP2KAK one...

Best Regards

Dimitri