Building shielding detection and shielding area compensation method by use of ghost images

Abstract

The invention discloses a building shielding detection and shielding area compensation method by use of ghost images. The method comprises the following steps: 1, performing secondary utilization on a result (ghost images) of conventional ortho-rectification; 2, performing shielding compensation by use of such a feature that ghost images are not geometrically deformed; and 3, performing shielding detection completely on buildings in aerial images, detecting ghost roofs (roofs obtained through the ortho-rectification) of the buildings in the ghost images and projection roofs by use of DBM, and by use of relations between the ghost images and shielding areas, determining that pixel areas occupied besides the roof portions of the buildings in the ghost images are the shielding areas. According to the invention, shielding detection is carried out by use of the method, and he problems of fake shielding and fake visibility existing in a conventional shielding detection method are eliminated. In the detection process, the building roofs in the whole images are firstly extracted, then gray processing is performed on the shielding areas, and the problem of coverage of the shielding areas when a part of the building roofs are re-detected after detection is avoided. The operation is simple, the shielding detection speed is improved, and the detection cost is decreased.

Description

technical field [0001] The present invention relates to the field of aerial photogrammetry, in particular to the technology and method in the field of real orthophoto generation, which is to deepen the use of traditional orthorectification results, so that ghost images can achieve the effect of real orthophotos. Background technique [0002] The ghost image described is: in the process of digital differential correction of aerial images using traditional ortho-rectification methods, since the building walls do not have a digital ground model, there are roof ghosts in the image generated by ortho-rectification phenomenon, such incomplete orthophotos are called ghost images; the roofs of buildings produced through traditional orthocorrection in ghost images are called ghost roofs. [0003] Urban digital orthophoto maps have the advantages of high precision, rich information, intuitive and realistic, and can be used as background information for building digital cities. It pro...

AI Technical Summary

Problems solved by technology

[0007] The present invention proposes a method for occlusion detection using ghost images to solve the problems of false visibility, false occlusion and buildings occluding buildings in previous occlusion detection methods.

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