Adaptive Thresholding Plug-In
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"
To: "Kevin Myers" ; "gimp users"
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
