Coherence-enhancing line drawing for color images

• Published in: Science China. Information sciences 2013-11, Vol.56 (11), p.77-87
• Main Authors: Wang, ShanDong, Ma, ZiYang, Liu, XueHui, Chen, YanYun, Wu, EnHua
• Format: Article
• Language: English
• Subjects: Algorithms; Color imagery; Computer Science; Image enhancement; Information Systems and Communication Service; Luminance; Research Paper; 亮度差; 基于图像; 实时性能; 彩色图像; 相干; 线描; 绘制方法; 边缘检测器
• ISSN: 1674-733X; 1869-1919
• DOI: 10.1007/s11432-012-4685-5

Line drawing plays an important role in many image-based non-photorealistic applications. However, most existing approaches use a grayscale edge detector for line extraction, so that only luminance differences between nearby image pixels is taken into account, but the chrominance differences is ignored. This leads to the undesirable consequence that visually significant edges in adjacent regions with different colors of similar luminance cannot be detected. To address this limitation, we present a novel enhanced line drawing method based on a flow-based difference-of-Gaussians （FDoG） filter. Because of an inherent property of the thresholded DoG edge model, captured lines may appear dislodged from the true edges in the image. To this end, we provide a gradient-guided warping technique so that smooth and coherent lines can be extracted in the correct location. The GPU implementation of the proposed algorithms allows real-time performance, and experimental examples with various color images demonstrate the method＇s superior qualitative performance over previous approaches.