On Thursday 02 November 2006 13:17, Ron Savage wrote: > On Wed, 1 Nov 2006 15:42:15 -0700, Brian Jackson wrote: > > Hi Brian > > I checked a couple of ImageMagick books I have, but found nothing > explaining the histograms. I did not try reading the source code...
And I'm not a C guy, so reading the source wouldn't help me much :\ I've got a little shell script to produce the 4 different histograms (value, red, green, blue) and it takes about 0.6-2.5 seconds depending on the machine, which isn't too bad, but not having to make a shell call, writing and then reading 4 files....that's the goal :) > > Think 'levels' from The GIMP or Photoshop. > > Here is what I'm looking for (obviously an underexposed image :) > > http://brianjacksonphoto.com/histogram > > Could you upload the histogram output of the 3 programs, on the same > image, side-by-side? That might tell us something. Well, the histograms that IM produces are similar to the ones that The GIMP produces, they are just presented differently. I've updated the page with new examples. I have also uploaded a screenshot of my little 'Levels' app written in Perl/TK, the one I'm trying to add features to. I didn't include all the channels from The GIMP, as I think that's just overkill on screenshots. > Also, since I don't have GIMP or Photoshop installed, I don't have > access to their on-line help, but perhaps their web sites explain > these 'levels'. - Levels is one of the main ways to adjust an image's color, the other main way is through 'curves'. Levels makes more sense to me, so that's what I use :) If you are familar with the 'Levels' call in PerlMagick, then that's what I'm using. I also think the CLI version is '-level' thanks, brian -- Brian Jackson Action Athletics Sports Photography [EMAIL PROTECTED] http://www.ActionAthletics.com/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
