中文摘要：

配准速度和精度是SAR图像配准效果的两个重要评价指标。SIFT算法是图像特征提取和描述的经典算法,SIFT特征具有尺度和旋转不变性,但SIFT算法的128维描述子在图像配准时会极大影响配准速度。为提高图像配准速度,首先提取图像SIFT特征点,然后用ORB算法定义特征点主方向的方法,赋予特征点主方向,最后结合特征点邻域图像块的矩特征,形成8维描述子,对图像中的SIFT特征点进行描述,实现SAR图像配准。实验结果表明,本文方法在保持SAR图像配准精度的前提下,极大程度地提高了配准速度。

英文摘要：

The speed and the precision are the two most important criteria for the result of image registration. Scale Invariant Feature Transform （SIFT） is a classical algorithm for feature extraction and description. The SIFT has the characteristics of scale invariance and rotation invariance, while the 128D descriptor has a big adverse effect on the speed of image registration. To improve the time-consuming descriptor, we propose a novel method. The SIFT feature points are extracted at first. Then, ORB algorithm is used to define the main orientation of the points. Based on the moments features of the feature points＇ neighborhood image block, a 8D descriptor is formed for describing the SIFT feature points of the image and realize SAR image registration. The experimental results demonstrate that the proposed method can improve the registration speed greatly while keeping the image registration precision.