sobel filter in matlab

To apply the Sobel filter in MATLAB for edge detection, follow these steps:

1. Read the image using the imread function:

img = imread('image.jpg');
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2. Convert the image to grayscale using the rgb2gray function:

gray_img = rgb2gray(img);
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3. Apply the Sobel filter using the edge function with the 'Sobel' option:

sobel_img = edge(gray_img, 'Sobel');
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4. Alternatively, you can apply the Sobel filter separately on the x and y directions using the imfilter function:

sobel_x = [-1 0 1; -2 0 2; -1 0 1];
sobel_y = sobel_x';

sobel_x_img = imfilter(double(gray_img), sobel_x);
sobel_y_img = imfilter(double(gray_img), sobel_y);

sobel_img = sqrt(sobel_x_img.^2 + sobel_y_img.^2);
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The resulting image sobel_img will show the edges in the original image detected using the Sobel filter.