MATLAB Answers


Hi! Question about image processing.

Asked by Portgas Ace on 9 Aug 2014
Latest activity Commented on by Image Analyst
on 15 Aug 2014
So I have here different retinal images and they all have different 'contrast'. What can I do to make these images have the same 'intensity' or 'contrast' or 'appearance' between them. Is there a way where for example an image seems dark, it will be contrasted to a lighter image and if it's a light image, it will be contrasted the other way around?


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1 Answer

Answer by Image Analyst
on 9 Aug 2014
Edited by Image Analyst
on 9 Aug 2014

You can try histogram matching like this algorithm:
The Image Processing Toolbox also has a imhistmatch() function in it. I also have a histogram matching routine in my File Exchange where you can make the histogram be any shape you like, for example below I make the histogram be the shape of the girl's silhouette:
Or you can play around with imadjust().
You might also look into HDR, High Dynamic Range Imaging.


hi! the link you've given about the colorhistwarp by mark grundland seems to be promising. But i cant seem to find a sample code for me to work with. We're allowed to use already working codes as long as we have understand how does it happen. If you could help me find a code to perform the colorhist warping, I would appreciate it really much.
Sorry, I'd like to have the Grundland algorithm in MATLAB code but I don't. If you code it up, please put it on the File Exchange. It is the best color histogram matching algorithm I've seen.

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