Abstract：The process of manually rendering traditional Chinese meticulous flower painting is complicated and highly skilled. The existing automatic line drawing colorization is difficult to generate natural and reasonable gradient effect. On the basis of condition generative adversarial network(CGAN), an interactive meticulous flower coloring algorithm via attention guidance is proposed to accomplish the colorization of meticulous flowers from line drawing. A color attention map depicting the color category and layout of flowers is designed to guide the proposed network to learn important color features in the training stage. The color attention map is considered as the means of interaction between the user and the system for color design in the application stage. In the network structure design, a local color-coding sub-network is constructed and trained to encode the flower color attention map. The encoded information is introduced into the conditional normalization process of each layer of the generator as an affine parameter to accomplish learning and controlling of colors. Since the depth features emphasize global semantic information, the local high-frequency information reflecting line features might be lost. A cross-layer connection structure is introduced into the generator network to strengthen the learning of line features. Experimental results show that the proposed algorithm renders line drawing of flowers better into meticulous flowers and the generated images are accordant with the color distribution and characteristics of real meticulous flowers with good artistic reality and appreciation.
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2020, Vol. 33 
