How to count the number of pixels from an image for specifies colors?
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I have used the code stated below.
if true
% code
imread color.jpg
load color.jpg
redChannel = color(:, :, 1);
greenChannel = color(:, :, 2);
blueChannel = color(:, :, 3);
whitePixels = redChannel == 255 & ...
greenChannel == 255 & ...
blueChannel == 255;
count = sum(whitePixels(:));
Red1Pixels = redChannel == 255 & ...
greenChannel == 166 & ...
blueChannel == 166;
count = sum(Red1Pixels(:));
Red2Pixels = redChannel == 254 & ...
greenChannel == 85 & ...
blueChannel == 82;
count = sum(Red2Pixels(:))
Blue1Pixels = redChannel == 179 & ...
greenChannel == 169 & ...
blueChannel == 250;
count = sum(Blue1Pixels(:))
Blue2Pixels = redChannel == 255 & ...
greenChannel == 255 & ...
blueChannel == 255;
count = sum(Blue2Pixels(:))
end
and I am getting error as below.
if true
% code
Index exceeds matrix dimensions.
Error in Try_03_07_2018 (line 17) greenChannel = color(:, :, 2); and Try_03_07_2018 is the file name.
Kindly help me out of this.
Regards,
Jotheeshwar V
0 Comments
Accepted Answer
More Answers (2)
Image Analyst
on 4 Jul 2018
Replace this
imread color.jpg
load color.jpg
with this
fileName = fullfile(pwd, 'color.jpg');
color = imread(fileName );
[rows, columns, numberOfColorChannels] = size(color);
if numberOfColorChannels < 3
errorMessage = sprintf('%s is not a color image!', fileName)
uiwait(errordlg(errorMessage));
return;
end
0 Comments
komal
on 7 Jun 2019
After doing skin detection. I want to count the pixels of white region which indicates skin part shown in the image.How can I do it? Please help me out
2 Comments
Image Analyst
on 7 Jun 2019
numWhitePixels = nnz(skinMask);
where skinMask is your binary image that you get after doing the skin detection (which I assume you already know how to do that part).
Jan
on 11 Jun 2019
Edited: Jan
on 11 Jun 2019
@komal: Please do no append a new question in the section for answers of another thread. Ask a new question instead.
"Not working" is a lean description of our problem. Please mention any details. Of course you can use nnz to count elements in an array. So if something is not working for you, you have to explain, what the inputs are, what you want to achieve and what you get instead: a result which differs from your expectations, or an error message?
Afert opening a new thread, delete this pseudo answer here. Thanks.
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