Edge Detection in Images Using Prewitt Operator

P0401: Implementing Prewitt operator for image edge detection effectively identifies edge features in images through horizontal and vertical gradient computations using 3×3 convolution kernels. The algorithm calculates approximate derivatives to highlight regions with significant intensity changes. P0402: Applying Laplacian of Gaussian (LoG) operator with different σ values enables multi-scale edge detection, where larger σ values produce smoother results by first applying Gaussian blur before Laplacian derivative calculation to reduce noise sensitivity. P0403: Canny edge detection provides clear edge results through a multi-stage algorithm involving Gaussian filtering, gradient calculation, non-maximum suppression, and double thresholding with hysteresis tracking for optimal edge connectivity. P0404: Image threshold segmentation partitions images into distinct regions by converting grayscale images to binary using global or adaptive thresholding techniques, implemented through functions like cv2.threshold() in OpenCV. P0405: Watershed threshold method segments images based on grayscale values by treating pixel intensities as topological surfaces and flooding from regional minima, requiring careful marker selection to prevent over-segmentation. P0406: Quadtree decomposition recursively divides matrices into smaller submatrices until blocks meet homogeneity criteria, efficiently representing hierarchical image structures through region splitting algorithms. P0407: Text-nontext classification separates image components using feature-based approaches including texture analysis, connected component properties, and machine learning classifiers trained on character shape descriptors. P0408: Morphological gradient detects binary image edges by performing dilation and erosion operations, then subtracting results to highlight object boundaries. This method uses structuring elements to enhance contour visibility while maintaining shape characteristics. P0409: Morphological operations remove current lines from PCB images by applying opening/closing transformations with linear structuring elements, preserving chip objects through selective filtering based on size and shape attributes for target extraction.