Understanding Kakadu and OpenJpeg "compression rate" options

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Cyril MASSET

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Oct 7, 2022, 9:29:27 AM10/7/22

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Hi,

I'm currently interested in working with OpenJpeg in replacement of Kakadu, and I wanted to know if there a link between the "-rate" Kakadu parameter and the "-r" OpenJpeg parameter.

(Till now I was using "- rate 2" with Kakadu.)

The documentation about the Kakadu parameter is quite complicated because it's directly linked to the complex jp2k compression algorithm. On the other side, the OpenJpeg documentation about its "-r" parameter is quite unclear ("20 means 20 times compressed").

The real question for me is : what do we lose when you increase the OpenJpeg "-r" parameter ? The ratio quality/filesize seems to remain excellent, and it's quite disturbing :D