Extraction of damaged area caused by debris flows in Hiroshima using COSMO-SkyMed images
Extraction of damaged area caused by debris flows in Hiroshima using COSMO-SkyMed images
复制标题
使用 COSMO-SkyMed 图像提取广岛泥石流造成的受损区域
DOI：
10.1117/12.2277679
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Suga Yuzo
中科院分区：
文献类型：
--
作者：
Konishi Tomohisa;Suga Yuzo
2014年8月20日，广岛市发生暴雨。暴雨诱发了泥石流和浅层滑坡。自然灾害发生后迅速评估损失对于启动有效的应急行动至关重要。合成孔径雷达（SAR）具有巨大的潜力，主要是由于其全天候昼夜成像能力。在这项研究中，我们研究了使用三个COSMO-SkyMed图像的泥石流造成的损坏区域的提取。利用COSMO-SkyMed图像对计算出的干涉相干、强度相关和归一化差σ零指数（NDSI）等提取方法，提取出了高分辨率遥感图像。在这项研究中，我们调查的适用性的方法提取的泥石流造成的破坏面积。将COSMO-SkyMed的单视复数据进行配准，计算干涉相干性。使用日本地理空间信息局（GSI）生成的10米网格数字高程模型（DEM）的干涉相干图像进行正射校正。从正射校正图像计算强度相关性和NDSI。对于受损区域的提取，我们研究了平均值和标准差的干涉相干性，强度相关性和NDSI使用前和共灾图像对。三种方法得到的平均值在灾前和灾后图像之间几乎都是增加的。因此，受灾地区的NDSI表明灾前和灾后图像之间有很好的分离。总之，NDSI在快速灾害响应阶段表现出良好的提取泥石流破坏区域的能力。
The heavy rain occurred in Hiroshima city on 20 August 2014. Then, debris flows and shallow slides were induced by the heavy rain. Rapid damage assessment after natural disasters is crucial for initiating effective emergency response actions. Synthetic Aperture Radar (SAR) has a great potential due primarily to its all-weather day-and- night imaging capabilities. In this study, we examined an extraction of damaged area caused by debris flows using three COSMO-SkyMed images. The extraction methods are interferometric coherence, intensity correlation and normalized difference sigma nought index (NDSI) calculated from COSMO-SkyMed image pair. In this study, we investigated the applicability of the methods for extraction of damaged area caused by debris flows. The single look complex data of COSMO-SkyMed were co-registered each other for calculating interferometric coherence. The interferometric coherence images were ortho-rectified using 10 m gridded Digital Elevation Model (DEM) generated by the Geospatial Information Authority of Japan (GSI). The intensity correlation and NDSI were calculated from ortho-rectified images. For damaged area extraction, we investigated the mean and standard deviation of interferometric coherence, intensity correlation and NDSI using pre- and co-disaster image pairs. The mean values derived from the three methods in damaged area almost increased between pre- and co-disaster images. As a result, NDSI in damaged area indicated good separation between pre- and co-disaster images. In conclusion, NDSI showed good capability for extraction of damaged area caused by the debris flows at a rapid disaster response phase.