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Indexable
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```2. Question: Convert a colour image to a grayscale image.
Solution:
% Convert image to grayscale
file
grayImage = rgb2gray(colorImage);
imshow(grayImage);
title('Grayscale Image');
3. Question: Convert a colour image to a grayscale image without using built-in function.
Solution: Gray=0.2989×R+0.5870×G+0.1140×B
file
% Extract the RGB components
R = colorImage(:,:,1); % Red channel
G = colorImage(:,:,2); % Green channel
B = colorImage(:,:,3); % Blue channel
% Compute the grayscale image using the formula
grayImage = 0.2989 * double(R) + 0.5870 * double(G) + 0.1140 * double(B);
% Convert the result to uint8
grayImage = uint8(grayImage);
% Display the grayscale image
imshow(grayImage);
title('Grayscale Image (Manual Conversion)');
4. Question: Resize an Image to half its original dimensions.
Solution:
% Resize the image to half the original dimensions
smallImg = imresize(img, 0.5);
% Display the resized image
imshow(smallImg);
title('Resized Image');

4. Write a script to generate negative of an image.
file
% Convert to grayscale if the image is in color
if size(img, 3) == 3
img = rgb2gray(img);
end
% Calculate the negative of the image
negativeImg = 255 - img;
% Display the original image
subplot(1, 2, 1);
imshow(img);
title('Original Image');
% Display the negative image
subplot(1, 2, 2);
imshow(negativeImg);
title('Negative Image');
5. write a script to generate negative of an image without using in-built function.
% Convert to grayscale if the image is in color
if size(img, 3) == 3
% Extract the R, G, and B channels
R = img(:, :, 1);
G = img(:, :, 2);
B = img(:, :, 3);

% Convert to grayscale using the luminance method
grayImg = 0.2989 * R + 0.5870 * G + 0.1140 * B;
else
grayImg = img;
end
% Initialize the negative image
[m, n] = size(grayImg);
negativeImg = zeros(m, n, 'uint8'); % Create an empty matrix of the same size
% Calculate the negative of the grayscale image
for i = 1:m
for j = 1:n
negativeImg(i, j) = 255 - grayImg(i, j);
end
end
% Display the original grayscale image
subplot(1, 2, 1);

imshow(grayImg);

title('Original Grayscale Image');
% Display the negative image
subplot(1, 2, 2);
imshow(negativeImg);
title('Negative Image');
```