how can i calculate and display the particular range of pixels in the image?

My main task is to highlight the particular pixel value by changing the color of that pixel. For example; we have a color image. I want to highlight a particular color in the image with the help of range of pixels.Can i have a code for this please.

Answer 1

[Image Analyst]

Set up a colormap and apply it. For example (untested)

grayImage = imread('cameraman.tif');
imshow(grayImage);
cmap = gray(256);
% Make gray levels 150 - 170 red
cmap(151:191, 1) = 1;
cmap(151:191, 2) = 0;
cmap(151:191, 3) = 0;
colormap(gca, cmap);
colorbar;
hp = impixelinfo();

[ABDUL WAHID MOHAMMED]

I can change the selected range of pixels in the image to red.How can i count the area or the count of the 'red color'(the range changed)?

[Image Analyst]

In the above example where you were interested in the range 150-170, and pseudocolored those pixels to red (in the display only, NOT by changing the original image values) by using a colormap, you can use imhist() and sum up those bins

[counts, grayLevels) = imhist(grayImage);
numPixels = sum(counts(151:171))