[Gdal-dev] Wanted: More speed to JPEG2000
Jukka.Rahkonen at mmmtike.fi
Thu Nov 23 09:39:14 EST 2006
I have noticed that there is quite a big difference between using ECW and JPEG2000 format images through GDAL and MapServer path. While I could get in a quite well controlled test some 120 images per minute ripped out from ECW layer it was just 80 image per minute from JPEG2000 layer with JP2ECW driver and miserly 25 images/min with JP2KAK driver.
I wonder if there is any chance to improve the JPEG2000 even close to ECW efficiency? Slow results with JP2KAK driver is propably due to not so optimal implementation, but is there some explanation for the difference between ECW and JPEG2000 with the ER Mapper driver?
I do know the great variety in how JPEG2000 files can be written. My images are created with the normal Kakadu recipe, RPCL progression order, lossless, without tiles but with precincts etc. If someone could suggest most suitable compression options for JP2ECW driver I am willing to do a quick test and report about the results.
For us this has practical meaning because we archive images as lossless and therefore we need to use JPEG2000. Images in everyday use are in TIF format but every now and then we need the archived images as well.
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