Bionic Face Sketch Generator.

Face sketch synthesis is a crucial technique in digital entertainment. However, the existing face sketch synthesis approaches usually generate face sketches with coarse structures. The fine details on some facial components fail to be generated. In this paper, inspired by the artists during drawing face sketches, we propose a bionic face sketch generator. It includes three parts: 1) a coarse part; 2) a fine part; and 3) a finer part. The coarse part builds the facial structure of a sketch by a generative adversarial network in the U-Net. In the middle part, the noise produced by the coarse part is erased and the fine details on the important face components are generated via a probabilistic graphic model. To compensate for the fine sketch with distinctive edge and area of shadows and lights, we learn a mapping relationship at the high-frequency band by a convolutional neural network in the finer part. The experimental results show that the proposed bionic face sketch generator can synthesize the face sketch with more delicate and striking details, satisfy the requirement of users in the digital entertainment, and provide the students with the coarse, fine, and finer face sketch copies when learning sketches. Compared with the state-of-the-art methods, the proposed approach achieves better results in both visual effects and quantitative metrics.