双边加权引导图像滤波

Bilateral weighted guided image filtering

针对经典方法对光晕等伪影抑制能力不足的问题,将双边权重嵌入到引导滤波中,提出一种新型局部方法称之为双边加权引导图像滤波.该方法目标函数为双边加权岭回归模型,此模型可通过双边滤波的迭代执行来求解.为提高计算效率,采用双边滤波的近似加速版本.通过对滤波核进行分析,可知双边加权引导图像滤波提供了比传统方法更灵活的保边及滤波控制.最后将该滤波方法的适用范围拓展到彩色图像上.为评估双边加权引导图像滤波,在保边模糊与人像磨皮这2种图像处理应用上进行试验,并进行了计算效率的对比分析.结果表明:与多数经典保边滤波方法相比,双边加权引导图像滤波产生的结果具有更好的视觉效果,所提出方法的指标BIQI、IL-NIQE、SSEQ分别达到20.082、47.026、53.103.

To solve the problem of insufficient suppression of halo artifacts in the classic methods,the bilateral weights were embedded into the guided filter to propose a new local method of bilateral weighted guided image filtering.The objective function was constructed as bilateral weighted ridge regression model,which could be solved by the iterative execution of bilateral filter.The fast approximation of bilateral filter was adopted to improve computational efficiency.Through the analysis on the filter kernel,it was shown that the more flexible edge-preserving and filtering control were provided by the proposed bilateral weighted guided filtering than traditional methods.The proposed method was extended for the color image filtering.The experiments on two image processing applications of edge-preserving smoothing and portrait skinning were conducted to evaluate the proposed method.The running efficiencies were compared and analyzed.The results show that the outputs produced by bilateral weighted guided filtering have better visual quality compared with those of most classic edge-preserving filtering methods,and the BIQI,IL-NIQE and SSEQ of the proposed method can reach respective 20.082,47.026 and 53.103.