In IM, there is a similar function called -level or +level. You can shift by raw values or by percent. I usually use percent.
-level stretches the histogram and +level compresses the histogram see http://www.imagemagick.org/Usage/color/#level http://www.imagemagick.org/Usage/color/#level_plus You can shift either the low (black) side or the high (white) side or both. There is also an automatic stretch function -auto-level The level functions adjust in a linear manner. You can adjust in a non-linear manner using -gamma, -evaluate pow, -sigmoidal-contrast. see http://www.imagemagick.org/Usage/color/ If you just want to mix some color with your image, you can do convert image -fill somecolor -colorize XX% result see http://www.imagemagick.org/Usage/color/#colorize I also have some unix shell scripts that you might want to look at: see autocolor, autogamma, autolevel, bcimage, clip, exposure, curves, plm, omnistretch, redist, stretch http://www.fmwconcepts.com/imagemagick/index.html Fred _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
