改进的形态学干涉图滤波方法

Improved morphological filtering algorithm of interferograms

在干涉合成孔径雷达滤波中由于去噪的同时会对干涉条纹产生平滑效应,导致干涉条纹细节信息丢失。针对这一问题,基于数学形态学原理,提出了一种改进的自适应梯度形态学重建滤波方法。首先,引入相位图像矢量化可有效保护相位条纹连续性。其次,改进自适应梯度估计方法,优化线结构元素选取以保护相位的细节信息。最后,结合改进的形态学开闭操作和基于膨胀及腐蚀的形态学重建操作对干涉图进行滤波处理。仿真和实测数据实验结果表明,该算法在有效去噪的同时,有较好的相位保持特性。

In interferometric synthetic aperture radar filtering,denoising has smoothing effect on interference fringes,which results in detail information loss of interference fringes.To solve this problem,this paper proposes an improved adaptive gradient estimation and morphological reconstruction filtering algorithm based on mathematical morphology theory.The algorithm firstly adopts interferogram conversion to protect the phase stripes effectively.Then improving adaptive gradient estimation for better line structure elements protects the phase details.Finally,the paper combines modified morphological opening and closing operation and morphological reconstruction with expansion and erosion operation to carry out filtering steps.Simulation and real data experiments show the proposed algorithm not only has effective performance on denoising,but has fine fidelity to the fringe information of interferograms.