image_vignetting 去图像暗角/光晕 《Single-Image Vignetting Correction by Constrained Minimization of log-Intensity Entropy》 效果 参考 https://www.cnblogs.com/Imageshop/p/6166394.html https://blog.csdn.net/piaoxuezhong/article/details/78333838 https://blog.csdn.net/lz0499/article/details/82054651