摘要
针对现有SAR影像增强方法消减相干斑噪声时造成细节区域信息破坏的问题,提出了一种基于直方图均衡偏微分(PDE)的改进算法。该方法在原有直方图均衡PDE模型的基础上,与ROF去噪模型相结合,利用边缘特征的图像梯度控制扩散系数,使边缘区扩散系数较小以保留边缘信息,非边缘区扩散系数较大以去除噪声,然后对去噪后的图像进行自适应校正,抑制因阶梯效应引起的图像平滑区不均匀现象。算法的优点为,去噪声与图像增强同时进行,实现减弱相干噪声影响,同时保留地物边缘轮廓。为验证本文算法的适用性,选择Sentinel-1A数据进行了实例试验,结果表明,该方法可以有效去除平滑区相干噪声斑,边缘与细节区域信息得到良好的保留。
In this paper,an improved algorithm based on histogram partial differential equalization（ PDE） is proposed. This algorithm overcomes the problem of information damage in detail region,caused by eliminating speckle noise in existing SAR image enhancement algorithm. The method is based on the original histogram equalization PDE model,and combined with the ROF（ Rudin Osher Fatemi）denoising model,the diffusion coefficient is controlled by the image gradient of edge features,and is kept small in edge region to retain edge information while big in non-edge region to remove noise. Then self-adaptive correction is applied to the denoised image,to suppress the unevenness in smoothing area of the image caused by ladder effect. The advantage of the algorithm is that de-noising and image enhancement are carried out simultaneously,so as to reduce the influence of coherent noise while preserving the contours of the edge of the feature. In order to verify the applicability of the algorithm,Sentinel-1 A data is selected for example test. The results show that this method can effectively remove the coherent noise in the smooth region,and the information in edge and detail region is well preserved.
作者
付睢宁
卢小平
卢遥
FU Suining;LU Xiaoping;LU Yao(Key Laboratory of Mine Spatial Information and Technology of NASMG,Jiaozuo 454003,China;National Quality Inspection and Testing Center for Surveying and Mapping Products,Beijing 100830,China;School of Surveying and Geo-Infnrmatics,Tongji University,Shanghai 200092,China)
出处
《测绘通报》
CSCD
北大核心
2018年第11期16-19,共4页
Bulletin of Surveying and Mapping
基金
2016年国家重点研发计划(2016YFC0803103)
河南省高校创业团队支持计划(14IRTSTHN026)
河南省创新型科技创新团队支持计划
