Landsat-8 Long Strip Ortho-product Generation And System Implementation

Landsat-8 satellite applies linear array push-broom method to obtain imagery,and then processed by scene to generate standard scene production.Nowadays there is expanding demand for wide area remote sensing data,long strip satellite data has higher value of application.Ordinarily,long strip satellite data is accessed by mosaiking several standard scenes of orthographic production.However,this classical method results in low efficiency,and may fail to acquire long strip satellite orthographic production when there is too much cloud.In order to overcome the shortages of the conventional method,a novel Landsat-8 long strip satellite orthographic method is proposed in this paper.The proposed method is conducted in the unit of the whole long strip satellite imagery and can be divided into three steps: ground control point correlation,long strip geometric precise correction and Ortho-rectification.First,the control points are correlated with the long strip sysmatic imagery using the Normalized Cross-correlation(NCC)method.Second,a more precise line-of-sight model is generated using the least squares adjustment.Finally,the long strip orthographic production is resampled by referencing to the digital elevation model(DEM).In the process of long strip precise adjustment,proper adjustment model based on strip constraint and optimization method of ground control points are introduced.Experiments are designed and conducted to verify the performance of the proposed long strip method.It turns out that when long strip imagery contains no more than fifteen scenes,the long strip satellite products produced by the proposed method achieve geometric accuracy within 12 m.At the same time,the processing efficiency of the proposed method is doubled compared with the conventional method.For scenes that covered by cloud,by using scenes around,the method in this paper can still produce long strip orthographic production which owns qualified geometric accuracy.In a certain scope of scenes,using the method in this paper can achieve qualified geometric accuracy and higher processing efficiency.Moreover,the proposed method has a better performance in the condition of cloud covering.