Three-dimensional building model simplifying method based on roof contour line

Abstract

A three-dimensional building model simplification method based on a roof contour line comprises the following steps: step 1, firstly, extracting a triangular patch of a roof surface, then carrying outcontour line rough extraction by using an Alpha Shapes algorithm, and then simplifying and regularizing a rough contour line; step 2, carrying out roof clustering segmentation by adopting an improvedRANSAC algorithm, and then obtaining an adjacency relation between roof surfaces through an inner contour line extraction method; step 3, correcting each feature line segment according to the relationship of vertex superposition, virtual intersection and over intersection between the inner and outer contour lines, and sequentially and orderly connecting the feature line segments to obtain a planeelement; step 4, for the non-planar primitives, processing and simplifying the non-planar primitives into rectangular isoplanar primitives through an integrity detection method; and step 5, finally,restoring elevation values of vertexes of all planar primitives and non-planar primitives, respectively projecting each vertex to the ground, and then connecting the corresponding vertexes to form a final simplified model. According to the invention, the data volume can be reduced.

Description

technical field [0001] The present invention relates to the field of computer graphics, in particular to an automatic simplification method for a three-dimensional building model using computer technology, which can automatically simplify the three-dimensional building model reconstructed by oblique photogrammetry into a regular building without relying on other prior information . Background technique [0002] With the popularity of UAVs, tilt photogrammetry technology has been widely used in the field of surveying and mapping. The technology uses the Structure of Motion (SfM) and Multi-View Stereo (MVS) methods in graphics to reconstruct a high-precision 3D city model through multiple sets of drone aerial photos, which greatly promotes the development of smart cities. Typical SfM and MVS methods first automatically extract and match the features between each pixel of the input image geometry, then restore the internal and external camera parameters in the picture, and the...

AI Technical Summary

Problems solved by technology

A large number of semi-automatic and fully automatic simplified systems have achieved certain results in recent years, but semi-automatic systems require too much human intervention, while fully automatic systems either rely on prior information (images and videos, etc.), or have strict assumptions about simplified models , such as strict requirements on shape, precision, etc., it is difficult to promote on a large scale

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