Grayscale Image Intensity Threshold

I have a greyscale image where each pixel is given an intensity value with 0 being black and 1000 being white. (not actual values just given as an example. I want to set a threshold for intensioty values so that pixels above this threshold are turned red.

How do i do this?

I thought if i did a hist(intensity values, 1000) then i could simply set the threshold by the bins i wanted included. For example i could say only values that are in the last 200 bins are the ones i want turned to red. Is it possible to specify Matlab to manipulate individual bins?

Answer 1

[Image Analyst]

You don't need to take the histogram. Simply threshold and set up the red, green, and blue color channels in a color image. See attached demo below in blue.