关键词: 素描人脸合成, 图像信息熵, 自适应分块, 感知哈希算法, 稀疏编码

Abstract: In order to solve the problems of blurred details and low definition of existing face sketch synthesis methods, this paper presents a face sketch synthesis method based on Perceptual Hash（pHash） algorithm and Sparse Coding（SC）. Firstly, according to the information entropy of the image, the photo-sketch pairs are adaptively divided into blocks. Next, the Hash fingerprints of the large image blocks are calculated by pHash algorithm, and the small image blocks are sparsely coded. Then, the [K] initial candidate photo blocks which are most similar to the test blocks are selected and the corresponding sketch blocks are obtained. Finally, the second sparse coding method is introduced to synthesize the final sketch block, and then the whole face sketch image is got. The validity of the algorithm is verified by existing face databases, which can be used for sketch face synthesis after optimization.

Key words: face sketch synthesis, image information entropy, adaptive block, perceptual hash algorithm, sparse coding