[Gdal-dev] What's the different between Kakadu and Japser

[Frank Warmerdam]

Fu Chen wrote:
> Hi!
> 
> I try to compress some landsat image into jpeg2000 loseless. Gdal provide two jpeg2000 library Kakadu and Japser. I
> think i can affort the register fee of Kakadu. But I don't know what's the different between them in the gdal
> document. Will Kakadu be more quick or something like GeoJ2 only implement in Kakadu not Jasper?
> 
> Is there someone like to give me some suggestion?

Fu Chen,

As Chris suggested in another message, the primary differences are performance
related.  Both support the geo extensions for JP2 (at least as used in
GDAL), but the JasPer performance library always read and decompresses
the whole image at full resolution.  This makes it very unsuitable for
large or very large images.  Also, I have found JasPer to use emmense amounts
of RAM to decode even what I would consider medium sized images (eg.3K x 3K).
And memory use aside, even at full resolution Kakadu is substantially faster
than JasPer.

However, if the image sizes you want to work with aren't too large, and
performance is not a pressing issue JasPer should be fine.

The "personal use" Kakadu license would likely do if you are just wanting
to use it for your own processing.  It is reasonably priced.  The
commercial licenses allowing redistribution of commercial executables are
pretty pricey.

Best regards,

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