Abstract: Low-poly is a popular style in the art design field recently. In order to improve the quality of image and video low-poly stylization, an image and video low-poly rendering method based on edge features and superpixel segmentation was proposed. Firstly, the intersection points of adjacent superpixels and the uniform sampling points of the difference set between feature edges and superpixel boundaries were extracted as the vertices of the triangle mesh, and Delaunay triangulation was performed to generate the initial triangle mesh. Then, the constrained quadric error metric method was used to simplify the generated mesh in order to generate the final triangle mesh. Finally, the triangle mesh was filled with color to obtain the image with low-poly style. For video low-poly rendering, the temporally consistent superpixels were used to track the same part of the object across frames to establish associations between the video frames, reducing the jitter after video rendering. In addition, the video segmentation method was used to segment the moving objects in the video, so as to obtain sampling points with different densities between the moving objects and the background, and the local stylized effect of the video was obtained by rendering the moving objects. Experimental results show that the proposed method can generate low-poly rendering results with better visual effects.

Key words: triangulation, temporally consistent superpixel, edge feature, low-poly rendering, uniform sampling

摘要： 低多边形是近来艺术设计界的热门风格。为了提高图像和视频低多边形风格化的质量，提出一种基于边缘特征和超像素分割的图像和视频低多边形渲染方法。首先提取相邻超像素的交点以及对特征边和超像素边界的差集的均匀采样点作为三角网格顶点，并执行Delaunay三角剖分来生成初始三角网格；然后采用带约束的二次误差度量方法对生成的网格进行简化，以生成最终三角网格；最后对三角网格填充颜色，得到了具有低多边形风格的图像。对于视频低多边形渲染，使用时间一致性超像素跨帧跟踪同一对象的相同部分，以建立视频帧之间的关联，降低视频渲染后的抖动。此外，采用视频分割方法分割视频中的移动对象，获得移动对象与背景之间不同密度的采样点，对移动对象进行渲染获从而得到视频的局部风格化效果。实验结果表明，所提方法能够生成具有较好视觉效果的低多边形渲染结果。

关键词: 三角剖分, 时间一致性超像素, 边缘特征, 低多边形渲染, 均匀采样