摘要
为了克服两种向全球开放的、不同数据源(ASTER和SRTM)DEM的获取技术缺陷,以甘肃省东部董志塬某测区为例,研究两种来源DEM的有效融合方案。首先,借助快速傅里叶变换(FFT)将ASTER和SRTM的DEM数据由空域转换到频域;然后,分别基于高通和低通滤波器进行滤波处理,并将滤波后的频域相加;最后,基于FFT逆变换将融合后的频域转换到空域,实现DEM数据的有效融合。误差分析表明:融合后的DEM最小、最大误差较融合前的均有明显降低,中误差也有降低趋势,误差绝对值大于30 m的网格点数占全部网格数的比例均有所下降。
In order to overcome the deficiency of sampling methods for SRTM and ASTER, the authors constructed a flow chart for SRTM and ASTER efficient fusion, with the DEMs of Dongzhi tableland as an example. Firstly, ASTER and SRTM were respectively transformed from spatial domain to frequency domain in terms of Fast Fourier Transform （FFF）. Secondly, the ideal high and low pass filters were respectively employed to remove their low and high frequency errors. Thirdly, the filtered frequency domains were added up. At last, the summed frequency domain was transformed to spatial domain in terms of inverse FFT. The results indicate that, compared with errors of ASTER and SRTM, both the minimum and maximum errors of the fused DEM show an obvious decrease, the RMSE has a weak decrease and the number of the errors bigger than 30 m is much less than that of SRTM and ASTER.
出处
《国土资源遥感》
CSCD
2010年第4期19-22,共4页
Remote Sensing for Land & Resources
基金
国家自然科学基金(编号:4090400)
国家高技术研究发展计划(863计划
编号:2009AA121401)
<科技导报>博士生创新研究计划资助项目(编号:KJDB200902-03)
