MATLAB: How to find “number of pixels” for a particular “gray level” in using HIST function

Question

Hi,

I am working on image processing.

In using the hist function, I want to know, how to get the "number of pixels" for a particular "grey level" and also for all the gray level value ?

Please help, Thank you in advance (^_^)

Answer 1

For a normal 8 bit (uint8) grayscale image I do this:

[pixelCounts grayLevels] = imhist(grayImage);

It's a lot trickier for double images. Let me know if you have double images - I think I have a demo on that.