PROGRESSIVE REGISTRATION OF IMAGE FEATURES AND 3D VECTOR LINES FOR ORIENTATION MODELLING

摘要

This paper proposes a progressive method to register image features and three-dimensional (3D) vector lines for image orientation modelling. Directed at images acquired with an approximate direct-georeferencing capability, this study employed 3D vector lines extracted from a geographical information system (GIS) database as ground control. The major work comprises three steps: (1) straight lines were parameterised and applied as control in the collinearity condition equations to determine exterior orientation parameters (EOPs); (2) coarse registration employed quadrangle features formed from straight lines to modify the initial EOPs; and (3) a two-step fine registration, initially involving all line-feature candidates, followed by the selection of the most probable one from neighbouring lines. Experimental results indicate that the proposed methods can achieve an accuracy of about 2pixels (close to the accuracy of the employed GIS database) from initial EOPs with more than 800pixel errors. Accuracy improvements in each step of the proposed coarse-to-fine registration are also demonstrated.