Image Edge Extraction Using Laplacian Filter, Gaussian Derivative Filter, and Difference of Gaussians Filter

Simple MATLAB code for extracting image edges using Laplacian filter, Gaussian derivative filter, and Difference of Gaussian filter. Image edge extraction represents a fundamental technique in image processing that enables identification and analysis of objects and contours within images. The Laplacian filter enhances image edges by computing the second derivative, making edges more distinct and prominent through zero-crossing detection. Gaussian derivative filters detect edge variations by computing first derivatives along horizontal and vertical directions, capturing subtle edge features through gradient magnitude calculation. The Difference of Gaussian filter applies Gaussian smoothing at different scales and computes their difference, effectively reducing noise while emphasizing edges through scale-space analysis. By combining these three filtering approaches and implementing corresponding MATLAB code using functions like fspecial, imfilter, and edge detection algorithms, we can achieve efficient extraction and analysis of image edges with proper parameter tuning for optimal results.