College of Computer Science and Software Engineering, Shenzhen University, Shenzhen 518060, China.
IEEE Trans Image Process. 2013 Feb;22(2):752-63. doi: 10.1109/TIP.2012.2222896. Epub 2012 Oct 4.
In this paper, we propose an image inpainting optimization model whose objective function is a smoothed l(1) norm of the weighted nondecimated discrete cosine transform (DCT) coefficients of the underlying image. By identifying the objective function of the proposed model as a sum of a differentiable term and a nondifferentiable term, we present a basic algorithm inspired by Beck and Teboulle's recent work on the model. Based on this basic algorithm, we propose an automatic way to determine the weights involved in the model and update them in each iteration. The DCT as an orthogonal transform is used in various applications. We view the rows of a DCT matrix as the filters associated with a multiresolution analysis. Nondecimated wavelet transforms with these filters are explored in order to analyze the images to be inpainted. Our numerical experiments verify that under the proposed framework, the filters from a DCT matrix demonstrate promise for the task of image inpainting.
在本文中,我们提出了一种图像修复优化模型,其目标函数是基础图像的加权非抽取离散余弦变换(DCT)系数的平滑 l(1)范数。通过将所提出模型的目标函数标识为可微项和不可微项的和,我们受到了 Beck 和 Teboulle 最近在该模型上的工作的启发,提出了一种基本算法。基于这个基本算法,我们提出了一种自动确定模型中涉及的权重并在每次迭代中更新它们的方法。DCT 作为一种正交变换在各种应用中都有使用。我们将 DCT 矩阵的行视为与多分辨率分析相关联的滤波器。探索了使用这些滤波器的非抽取小波变换,以便分析要修复的图像。我们的数值实验验证了在提出的框架下,DCT 矩阵的滤波器在图像修复任务中具有很大的潜力。