How to find number of Pixel green colour image by using webcamera

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clc
clear
clear all
images= []
webcamlist()
cam= webcam(2)
preview(cam)
pause(2);
images= snapshot(cam)
imshow(images)
r_channel= images(:,:,1);
g_channel= images(:,:,2);
b_channel= images(:,:,3);
images(:,:,1) =0;
images(:,:,3) = 0;
image(images);
mask= g_channel > 100, b_channel > 800, r_channel < 800, b_channel < 0, r_channel < 0;
numBlackPixels = sum(~mask(:))
gr_ratio = double(g_channel)./double(r_channel);
gb_ratio = double(g_channel)./double(b_channel);
rb_ratio = double(r_channel)./double(b_channel);
% gr_ratio(isnan(g_ratio))=0;
% grayImage = rgb2gray(image);
% binaryImage = grayImage > 20;
% binaryImage = bwareaopen(binaryImage, 50);
% binaryImage = imfill(binaryImage, 'holes');
% grayImage(~binaryImage) = 0;
falseMatrix= zeros(7,7);
targetMatrix= ones(7,7);
checkMatrix= ones(7,7);
fprintf('mask has %d black pixels.\n', numBlackPixels);
if targetMatrix == checkMatrix
% cam = camStop;
return
end
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Accepted Answer

Image Analyst
Image Analyst on 13 Oct 2021
Use the Color Threshold app on the Apps tab of the tool ribbon to define "green". Full demo is attached.
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More Answers (1)

yanqi liu
yanqi liu on 14 Oct 2021
sir,may be you should upload your image file to develop some function

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