MATLAB: How can i Change pixel color

color changeImage Processing ToolboxMATLABpixel colors

Hello

I have a color image of type RGB and I need to change the color of each point (red, yellow, orange) to green. I hope that there is a programmatic solution to this problem.

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I = imread('red.jpg');
figure,subplot(121),imshow(I)
th = 20;
[x,y,~]=size(I);
for ii=1:x
    for jj=1:y
        if((I(ii,jj,1)-th)> I(ii,jj,2)&& (I(ii,jj,1)-th)>I(ii,jj,3))
            I(ii,jj,1) = 0;I(ii,jj,2) = 255;I(ii,jj,3) = 0;
            
        end
    end
end
subplot(122),imshow(I)

For same effect you can try this

I(ii,jj,1:2) = circshift(I(ii,jj,1:2),1);

I(:,:,1:2) = circshift(I(:,:,1:2),1,3);%without for loop

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That's not a gray scale image you attached, it's an RGB image. So try this

rgbImage = imread('C1fig.jpg');
whos rgbImage
subplot(2, 1, 1);
imshow(rgbImage);
title('Original RGB image C1fig.jpg');
axis('on', 'image');
impixelinfo
mask = rgbImage(:, :, 1) == 0;
% Extract the individual red, green, and blue color channels.
redChannel = rgbImage(:, :, 1);
greenChannel = rgbImage(:, :, 2);
blueChannel = rgbImage(:, :, 3);
redChannel(mask) = 255;
greenChannel(mask) = 0;
blueChannel(mask) = 0;
% Recombine separate color channels into a single, true color RGB image.

rgbImage = cat(3, redChannel, greenChannel, blueChannel);
subplot(2, 1, 2);
imshow(rgbImage);
axis('on', 'image');
impixelinfo
title('Altered RGB image');

If it really is a gray scale image, you can try this:

grayImage = imread('C1fig.jpg');
if ndims(grayImage) == 3;
	grayImage = rgb2gray(grayImage);
end
whos grayImage
subplot(2, 1, 1);
imshow(grayImage);
title('Original image C1fig.jpg');
axis('on', 'image');
impixelinfo
mask = grayImage == 0;
% Initialize the individual red, green, and blue color channels.
redChannel = grayImage;
greenChannel = grayImage;
blueChannel = grayImage;
redChannel(mask) = 255;
greenChannel(mask) = 0;
blueChannel(mask) = 0;
% Recombine separate color channels into a single, true color RGB image.
rgbImage = cat(3, redChannel, greenChannel, blueChannel);
subplot(2, 1, 2);
imshow(rgbImage);
axis('on', 'image');
impixelinfo
title('Altered RGB image');

MATLAB: Turn background to one color

Threshold the image and do your thresholding to get your binary image. Then follow Steve's directions if you want the detected regions in the overlay. http://blogs.mathworks.com/steve/2009/02/18/image-overlay-using-transparency/

If you want the blue to be "burned in" to an RGB image, then you need to first get the individual color channels, and then do

redChannel(binaryImage) = 0;
greenChannel(binaryImage) = 0;
blueChannel(binaryImage) = 255;
rgbImage = cat(3, redChannel, greenChannel, blueChannel);

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