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CLAHE Crashes on HDR images

Posted: 2018-12-03T03:34:08-07:00
by whugemann
OK, I have just verified that it is fixed in the current version 7.0.8-15. But I still cannot see any inluence of the clip-limit parameter. In Fiji/ImageJ its influence is quite drastic, the default value beeing 3.0. In ImageMagick, I cannot see any difference, regardless what value I supply for it. And https://www.imagemagick.org/script/comm ... .php#clahe gives no hint on what values IM expects for this parameter. Questions:
  • Is it a real or an integer value?
  • What is the range?
  • I am confused by the {+-} in front of the last two parameters. To my knowledge, most commands expect a plus a the default, as with lat, and a negative parameter tells the command something different. But how can you possibly have a negative count of histogram bins? Or what would a negative contrast threshold possibly mean?
BTW: Unless I missed something, the https://www.imagemagick.org/script/comm ... ptions.php page is hard to find via the web interface. (I landed on https://www.imagemagick.org/script/magick.php, where the option is not yet discribed.)