Image Processing B&W Picture Calculate Color Percentage

I'm trying to do image processing on a B&W image.

I want to select a certain grayscale color and find out the perfectage of pixels that are lighter than that value.

Any starting points or code to help would be greatly appreciated. Thanks!

Answer 1

[Shunichi Kusano]

Hi Andar, this is the sample code.

img = imread('cameraman.tif');
imshow(img);
th = 100; % threshold to select brighter pixels
totalPixelNumber = numel(img);
%% method 1: making binary image
bw1 = img > th;
imshow(bw1)
nnz(bw1) / totalPixelNumber * 100% percentage
%% method2: finding brighter pixels directly
pixels = find(img > th);
length(pixels) / totalPixelNumber * 100% percentage

hope this helps.