纹理频谱分析的高分辨率遥感影像最佳尺度选择

Optimal spatial scale choosing for high resolution imagery based on texture frequency analysis

基于对纹理频谱的分析提出了一种高分辨率遥感影像最佳尺度的选择方法。首先,分析四种典型地物在傅里叶变换频域的频谱响应特性。然后,采用点扩散函数对原始影像进行尺度扩展,进而根据地物纹理的径向与角向曲线随尺度扩展的变化选择最佳尺度。最后,通过分析四种地物在6个尺度下的纹理特征可分性,说明本文方法能客观反映出地物的尺度效应,具备最佳尺度选择的可行性。利用支持向量机对QuickBird全色影像进行面向对象的分类,实验结果表明在最佳尺度下可取得较高精度。

Choosing the optimal spatial scale is one of the crucial issues in the field of remote sensing.In this paper,an approach,which is based on texture frequency analysis is proposed to determine the optimal spatial scale for high resolution imagery.Firstly,four typical geo-objects are used to analyze their frequency properties of the response to the Fourier transform domain.Secondly,the original image is up-scaled to different spatial resolutions using point spread function.The adequate spatial scale is chosen according to the change patterns in the radius distribution and angle distribution curves of geo-object texture with up-scaling.Finally,the separability among four types of geo-objects at six scales is analyzed based on the texture feature to approve the feasibility of the new method.The object-based classification of the QuickBird panchromatic image by means of SVM is implemented,and results of experiment demonstrate that the higher accuracy can be obtained at the optimal spatial scale.