关键词: 图像去噪, 高阶变分模型, 正则项, 边界保持, 阶梯效应

Abstract: To improve the edge preserving ability of current high order models, this paper proposes a new high order variational energy function by introducing the gradient information after convolution as the weighting function of second derivative, and leads to a fourth-order partial differential equation diffusion model. In the procedure of constructing the weighting coefficients, this paper gives a scheme that makes weighting function have the ability to preserve a certain edge based on the analysis of classical second-order total variation diffusion model. This weighting function can determine local structure region of the image and adapt the diffusion rate, as well as avoid boundary oscillations with good retention properties of the detail. The experimental results show that the proposed model can relief staircase effect, avoid oscillations and preserve edges while removing noise.

Key words: image denoising, high order variational model, regularization term, edge preserving, staircase effect