Color transfer, which plays a key role in image editing, has attracted noticeable attention recently. It has remained a challenge to date due to various issues such as time-consuming manual adjustments and prior segmentation issues. In this paper, we propose to model color transfer under a probability framework and cast it as a parameter estimation problem. In particular, we relate the transferred image with the example image under the Gaussian Mixture Model (GMM) and regard the transferred image color as the GMM centroids. We employ the Expectation-Maximization (EM) algorithm (E-step and M-step) for optimization. To better preserve gradient information, we introduce a Laplacian based regularization term to the objective function at the M-step which is solved by deriving a gradient descent algorithm. Given the input of a source image and an example image, our method is able to generate continuous color transfer results with increasing EM iterations. Various experiments show that our approach generally outperforms other competitive color transfer methods, both visually and quantitatively.
翻译:在图像编辑中起着关键作用的彩色转换最近引起了人们的注意。 由于诸如耗时的手工调整和先前的分割问题等各种问题,它至今仍是一个挑战。 在本文中,我们提议在概率框架下建模彩色转换,并把它作为一个参数估计问题。 特别是,我们将传动的图像与高山混合模型(GMMM)下的示例图像联系起来,并将传动的图像颜色视为GMM机器人。 我们在优化时使用期望-最大化算法(E-step和M-step) 。 为了更好地保存梯度信息,我们将基于拉普拉西亚的正规化术语引入M-step的目标函数,该函数通过生成梯度下降算法解决。考虑到源图像和示例图像的投入,我们的方法能够产生连续的彩色转换结果,同时增加EM iteration。 各种实验显示,我们的方法一般都比其他竞争性的彩色转换方法(包括视觉和定量)。