Positioning Method Of Multi-Source Domestic Satellite Imagery Based On Reference Geographic-information Data

Satellite images-based accurate positioning without ground control point information is the precondition for obtaining global geographic and resource environmental information and monitoring changes in the global resource environment.To obtain the high-precision positioning of high-resolution satellite images,because of the lack of control point constraints,using the parameters that require adjustment as the free unknown parameter result in the morbidity(rank loss)of the normal equation matrix,causing instability of the adjustment accuracy and distortion of the triangulation caused by the error excessive accumulation.Overall,in theory,the differences between the control adjustment and the GCP-independent adjustment are as follows:several field measurement control points are used in the control adjustment,he accuracy is high,and the consistency is good.Therefore,the GCP-independent block adjustment of satellite images can be consideredas,in the case that no ground control points are available,the overall block adjustment of the multi-source optical satellite imagery with specific constraints(distance,angle,etc.).Most GCP-independent adjustment uses a form of virtual control points;however,the precision of these virtual control points is low(varied system error)and the precision is not consistent in the measurement area.As a result,the GCP-independent adjustment is a type of block adjustment under different precision control;the law oferror propagation of this approach is more complex,and gross error detection and positioning are more difficult to perform using this approach.In summary,refence by Google Earth,Landsat/ETM,SRTM DEM,National Basic Surveying and Mapping Data,and other geo-information data with verifiable accuracy,used domestic high-resolution satellite imagery(such as ZY-3,GF-1)as the main data sources.based on super-multi-core computers(cloud servers),high-performance GPU/CPU cluster computer systems,and high-performance storage computing platforms for high-speed storage and transmission networks,we research a kind of efficient,high-precision,and intelligent geometric positioning method that do not depend on ground control information.This method achieves tie points and reference control points automatic extraction of multi-source domestic satellite imagery and large-scale block adjustment processing with stereo satellite imagery and single scene coverage satellite imagery,which can provide high-precision orientation parameters for rapid generation of high-precision maps.The specific research content is as follows:(1)GCP-independent satellite imagery block adjustment-GISIBABased on the“Alternate Direction Method”and RFM-based least square overall block adjustment,we proposed a GCP-Independent Block Adjustment method-GISIBA.In this method,the "average" virtual control points are built,though the points,on the one hand,the "rank" problem led by non convergence in GCP-independent block adjustment can be solved,on the other hand,our method can make full use of the randomness of residual systematic errors of the stereo satellite images having the same coverage area in a long time sequence to carry out the GCP-independent block adjustment,without relying on the third-party geospatial data and ground control points,and allow qualitative and quantitative analysis of the relations between the result of block adjustment without GCP,the imagery coverage degree and the time interval of imaging.(2)Large-scale block adjustment with domestic high-resolution satellite imageryLarge-scale block adjustment processing with stereo satellite imagery and single scene coverage satellite imagery can be achevied if third-party geographic information data is introduced as horizontal and vertical constraint.After automatic detecting and rejecting of gross errors and soluting of large-scale normal equations,it can provide high-precision orientation parameters for rapid generation of high-precision maps.The mosaic problem of the adjacent areas in large area DOM production also can be solved.(3)Tie points and reference control points automatic extraction of multi-source domestic satellite imageryUsing the overall matching strategy based on the significant edges extracted on the image to achieve rapid elimination of image systematic errors in the unusual initial positioning.Tie points and reference control points automatic extraction is achevied based on an object-based adaptive high-precision correlation matching algorithm(Image-Reshaping).A coarse-to-fine multi-level pyramid image matching strategy is adopted in image matching processing,and directional quality control is introduced in the matching strategy.(4)Parallel computing of image precise positioning algorithm in parallel distributed architecture with multi-core CPU/GPU clustersIn order to ensure the efficiency of tie points and refence control points automatic extraction and block adjustment processing,a parallel process based on OMP is used to achieve multi-process parallelization with point feature extraction and matching as"parallel granularity" to complete multi-core CPU and GPU for high-speed local area networks.Parallel computing of image precise positioning algorithm in parallel distributed architecture with multi-core CPU/GPU clusters is achieved.Finally,based on the existing distributed parallel architecture and high-resolution satellite imagery mapping software(PixelGrid-GlobalMapping)developed by the author and team,typical experimental areas and domestic satellite imagery(such as ZY-3 and GF1)were selected,large-scale processing experiments were conducted to test the accuracy of the algorithms,and verify the validity and generality of this research method.The method proposed in this paper can be widely applied to the high-precision and GCP-independent geometric positioning of satellite images in difficult areas.The software system was actually applied and improved in the 2016 and 2017 global mapping trial production,providing technical support for the global geographic information resource construction project and the production of domestic optical satellite imagery high-precision mapping products.