Map registration of image sequences using linear features

This paper proposes an automatic and fast algorithm for registering aerial image sequences to vector map data using linear features as control information. Our method is based on the extraction of linear features using active contour models (also known as, snakes), followed by the construction of a polygonal template upon which a matching process is applied. To accommodate more robust matching, this work presents both exact and inexact matching schemes for linear features. Additionally, in order to overcome the influence of the snakes-based extraction process on the matching results, a matching refinement process is suggested, Using the information derived from the matching process, we then determine the transformation parameters between overlapping images and generate a mosaic image sequence, which can then be registered to a map. The performance of the proposed scheme was tested on sequences of aerial imagery of 1 m resolution that were subjected to shifts and rotations using both the exact and inexact matching scheme, and was shown to produce angular accuracy of less than 0.7 degrees and positional accuracy of less than two pixels.