Edge Extraction of Ancient Books Based on Freeman Chain Code

With the passage of time and improper preservation methods, many ancient books and texts have disappeared in our world. How to preserve ancient books which carry excellent traditional Chinese culture has also become a problem of people's concern. One of the most popular discussions and the most modern methods is to digitize ancient books. This paper proposes a digital processing method for ancient books based on Freeman chain code. The process of the method is, firstly, to gray the acquired image with the maximum grayscale method, then to perform median filtering and morphological denoising to get the clear image edge. Finally, the processed image is extracted with the Roberts operator, and then the continuity of the edge is strengthened through Freeman chain code to obtain a clear and continuous edge of ancient text. The experimental results show that the proposed method can extract the text edges quickly and accurately, providing an effective method for further research on the digital processing of ancient books.