Adjusting CData to match CLim for grayscale Image

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I have a grayscale image in a figure displayed through imshow. I adjust the axes CLim limits [a b] to improve it's contrast to desired levels. How can I adjust the image matrix (CData) to match the image displayed by my CLim limits? I've tried imadjust function i.e. Image2=imadjust(Image1,[a b],[]) , but the resultant Image2 contrast doesn't look like the one displayed by CLim limits [a b].

Accepted Answer

Walter Roberson
Walter Roberson on 21 Apr 2016
t = double(max(min(Image1, b),a));
adjusted_image = (t - a) / (b - a);
now adjusted_image is in the range 0 (corresponding to a) to 1 (corresponding to b). Remember to caxis([0 1])

More Answers (1)

Image Analyst
Image Analyst on 21 Apr 2016
What are you trying to do? If you want to stretch contrast, you can pass in the values you want for black and white into imshow(). Or else call caxis(). I don't understand why you would ask what you asked.
  4 Comments
Walter Roberson
Walter Roberson on 22 Apr 2016
The intermediate images probably would not be too large.
John
John on 22 Apr 2016
Thanks Robert. I had the GUI ready, just needed that part of adjusting the matrix. I've employed the mat2gray. I agree the caxis is more efficient, but I'm working with very small images (about 128x128pixel, 8bit) so in the end, the memory isn't an issue for now. I'll implement your suggestion if need be in the future.

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