Legacy ImageMagick Discussions Archive

All,

I am new to Imagemagick and want to duplicate photoshop like levels (10, 245, 0.95) on my Image. I am seeing a complete washout of the image, what am I missing?
convert IMTEST.jpg -level 10,245,0.95 IM.jpg

IM -level values for min and max, depend upon the Q level of your IM compile. check convert -version. I assume it will say Q16, which means that IM is expecting values in the range of 0 to 65535. So you need to convert your values of 0 to 255 to the range of 65535 or what I usually do is convert the values to percent and use that

10/255 = 0.03921568627451 (x100 to get percent)
245/255 = 0.96078431372549 (x100 to get percent)

so try

-level 3.921%,96.08%,0.95

The gamma value (0.95) does not need any conversion.


see
http://www.imagemagick.org/script/comma ... .php#level

For new users of IM, see

http://www.imagemagick.org/script/comma ... ptions.php
http://www.imagemagick.org/script/comma ... essing.php
http://www.imagemagick.org/Usage/reference.html
http://www.imagemagick.org/Usage/

To duplicate PS levels output values, follow the above command with +level outputmin,outputmax

That works , Thank you so much for all the links as well!