MATLAB Implementation of a Grayscale Image-Based License Plate Localization Algorithm

This paper presents a grayscale image-based license plate localization algorithm implemented in MATLAB. The algorithm employs effective image processing techniques for detecting and precisely locating license plates within vehicle images. This approach finds applications in various domains including traffic monitoring systems, license plate recognition, and vehicle management solutions. The implementation involves key image processing steps such as grayscale conversion, edge detection using operators like Sobel or Canny, and morphological operations for candidate region selection. We provide detailed explanation of the algorithmic workflow including preprocessing techniques, feature extraction methods, and validation mechanisms. The MATLAB code structure includes main functions for image input handling, threshold calculation, region property analysis using bwlabel and regionprops functions, and spatial filtering based on aspect ratio and area characteristics. Sample implementations demonstrate practical usage scenarios with performance metrics. Furthermore, we discuss the algorithm's advantages in computational efficiency and limitations in complex lighting conditions, along with potential improvements through adaptive thresholding and machine learning integration for enhanced robustness.