To reduce shipbuilding costs or add automation to older ships with minimal hull modification, this paper introduces a meter recognition method based on image processing. Initially, the captured image undergoes a series of preprocessing steps, including cropping, grayscale conversion, and binarization. Subsequently, Hough circle detection determines gauge blockage, followed by angle determination for an exposed gauge pointer using the rotating virtual straight line technique. Finally, the angle is translated into an indication based on the functional relationship between the pointer angle and the meter reading. This paper’s algorithm is validated in a Python development environment using the OpenCV vision library, and the results demonstrate that the algorithm is highly accurate and suitable for real ship operations.