With the rapid development of computer graphics and image technology and 3D modeling, great progress has been made in the field of 3D digital relief. Hollowed out relief is a form of concave relief, which is obtained by carving out the background plane on the basis of concave relief. Digital relief is generated by computer-aided modeling, which overcomes the shortcomings of traditional manual relief, such as low production efficiency and difficult to modify products, and is easy to save. In this paper, the design and implementation of image relief based on computer 3D modeling, the basic modeling process of computer 3D modeling, plane relief and the generation method of fractal pattern concave relief based on distance transformation are discussed. A differential algorithm is proposed to realize the concave convex effect of image relief. Experiments are carried out on different models on laptops configured as main frequency and graphic display card to verify the rationality of the above algorithm. The time consumption of viewpoint selection of different models is tested, and the modeling efficiency of different input models is counted. The test results show that without program optimization, the viewpoint selection time of the model with the number of mesh patches of 15K ~ 50K ranges from 14 to 58s, among which the development of model visibility judgment and significance calculation is the largest, accounting for about 50% ~ 60% of the running time of the whole process. Therefore, the algorithm optimization of visibility judgment will help to improve the operation efficiency of the system and reduce the waiting time of users. Under the same input model, the computational efficiency of this algorithm is hundreds of times higher than that of the literature method. For the models in the table, due to the complex occlusion degree of patches, the modeling time of shallow relief is up to 3.778 seconds; For the mesh model with the number of patches below 35K, the efficiency of bas relief modeling is about, which basically meets the requirements of real-time.
