无有效重叠区域的SAR图像拼接方法

机载SAR雷达在成像时,由于受各种随机噪声因素的影响,在其所生成的相邻图像帧间存在小的重叠、断裂或者错位,因此常常不能提取出满足独特性要求的特征子图像.针对此类SAR图像序列的拼接,给出了一种新的无有效重叠区域的SAR图像拼接方法.该方法先利用图像特定点地理坐标以及载机航迹角进行粗拼接;然后提取邻接处附近的显著线状特征,同时对这些特征进行较精确的匹配定位;最后对拼接处的像素灰度进行融合,以避免出现明显的接缝.实验结果表明,新方法在进行无有效重叠区域的SAR图像拼接时,取得了较好的拼接效果.

A Novel Mosaic Method for SAR Image Sequences with Deficiency of Overlap Portion

It is usually difficult to extract feature regions from two successive frames of SAR imagery which lack overlapping portion, because the effects of different random noise during the flight when forming SAR images. A new mosaic method for this sort of SAR sequential imagery is presented. Firstly, the flight information of the plane and geographical coordinates of several feature points in SAR images are used to conduct a rough match. And then, a detailed approach based on remarkable linear features extracted in adjacent areas of two images is used to determine the corresponding positions of two images, which can subtly mosaic the sequential images. Finally, the gray levels between two stitched images are fused to eliminate the remarkable seam. Experimental results testify that this algorithm is able to seamlessly stitch two successive images automatically.