Yes Lourens, I have already tried simple things like that. Unfortunately there is far too much variation within each individual image for that to be successful. Thanks for the suggestion though anyway.
s/KAM ----- Original Message ----- From: "Lourens Veen" <[EMAIL PROTECTED]> To: "Kevin Myers" <[EMAIL PROTECTED]>; "gimp users" <[EMAIL PROTECTED]> Sent: Thursday, October 17, 2002 4:32 AM Subject: Re: [Gimp-developer] Adaptive Thresholding Plug-In On Thursday 17 October 2002 02:15, Kevin Myers wrote: > Hello, > > Has anyone out there already written or come across a GIMP > plug-in or script that is designed to do adaptive thresholding of > an image? > > I have a large number of extremely large scanned grayscale images > that need to be converted to black and white. Problem is that > the contrast and especially brightness of these images vary, not > only between different images, but also over different areas of a > single image. It is NOT adequate to choose a single threshold > value that will work across all of these images, or even across > the entire portion of a single image. > > I've tried using the Adaptive Contrast plug-in as a preprocessor > step to thresholding, but that plug-in doesn't seem to be giving > me the appropriate level of contrast boost and brightness shift > that would be needed. Have you tried doing an Image->Colors->Auto->Stretch Contrast before tresholding at a fixed value (say 128)? I'd say that that should help a great deal. Lourens PS: I think this one belongs in gimp-user, not gimp-devel. Please CC me, I'm not on gimp-user. -- GPG public key: http://home.student.utwente.nl/l.e.veen/lourens.key _______________________________________________ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
