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Leslie Smith

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20 Nov 2008 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith adaptive histogram eq..., clahe, histogram equalizatio..., image processing 52 10
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17 Jun 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith

The full argument list is
runCLAHE(Image,XRes,YRes,Min,Max,NrX,NrY,NrBins,Cliplimit,modHist)
The comments in the beginning of the function describe the arguments.
Once again I will suggest you use adapthisteq in the Image processing toolbox because Matlab's routine is more robust.

12 May 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith

The "Subscript indices must either be real positive integers or logicals" is basically that the index is out of bounds.

Obviously you are taking a class where the assignment is to create the CLAHE code. IMO, that is what you should do because the goal of a class is the learning, not the grade.
11 May 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith

I suggest you use adapthisteq in the Image processing toolbox because Matlab's routine is more robust.
Although you don't say what the error is, my guess is that it is "index out of bounds" for the look up table LUT. If I remember correctly, runCLAHE needs for the dimensions of the image to be even to work properly. Again, you are likely better off to use adapthisteq.
20 Nov 2008 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith

Thanks for the reference. I had looked for and did not find the Matlab CLAHE and was surprised when I thought it did not exist.
Leslie
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27 Oct 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith xj, LIAO

quite useful! thanks a lot!
17 Jun 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith Smith, Leslie

The full argument list is
runCLAHE(Image,XRes,YRes,Min,Max,NrX,NrY,NrBins,Cliplimit,modHist)
The comments in the beginning of the function describe the arguments.
Once again I will suggest you use adapthisteq in the Image processing toolbox because Matlab's routine is more robust.

17 Jun 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith Rado

Excuse me, this may be a stupid question, but can you tell me how to use this function?

I tried to define the variable "Image" to be the path of the image I want to process. Then I removed the comment symbols in front of:
% [XRes,YRes]=size(Image);
% CEimage = Image;
in "runCLAHE.m".

I typed the command:
J=runCLAHE(Image);

The error I got was:
?? Input argument "Cliplimit" is undefined.

Error in ==> runCLAHE at 34
if Cliplimit == 1

Can you help me with that?

Again, sorry for the stupid question and thanks in advance!
12 May 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith Smith, Leslie

The "Subscript indices must either be real positive integers or logicals" is basically that the index is out of bounds.

Obviously you are taking a class where the assignment is to create the CLAHE code. IMO, that is what you should do because the goal of a class is the learning, not the grade.
12 May 2011 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith Freyssineta

When i execute runCLAHE.m the error is "Subscript indices must either be real positive integers or logicals"

yup i know about adapthistheq function in matlab. But i did'nt allowed to use that function with my lecturer so i must make clahe code manually.
What should i do?
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adaptive histogram equalization, clahe, histogram equalization, image processing
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20 Nov 2008 Contrast Limited Adaptive Histogram Equalization (CLAHE) Best to read the reference in "Graphics Gems IV", Academic Press, 1994 pages 474-485 Author: Leslie Smith adaptive histogram eq..., clahe, histogram equalizatio..., image processing 52 10
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4.7 | 3 ratings

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