Abstract：In the satellite orthophoto database, the real boundaries of orthophoto images can significantly improve the accuracy and speed of operations such as spatial query and coverage analysis. This paper proposes and implements an image boundary extraction method based on Pixel-Following algorithm and Douglas-Peukcer algorithm. After the identification of background pixel value of the image, the boundary is tracked using the Pixel-Following algorithm, and then the redundant vertexes of the boundary are deleted using the Douglas-Peukcer algorithm. This method has been deployed in the satellite orthophoto database, and the results show that this method can extract the real boundary of the orthophoto image stably and accurately, with good application effects achieved.
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2017, Vol. 29 
