City Documentation: Creation and Visualization of High Resolution Panoramic Image Mosaics

Abstract

We present a novel system for 2D city documentation utilizing panoramic image mosaics. Current panoramic stitching methods often produce poor results and available visualization tools are not able to deal with high resolution panoramic image mosaics. For the construction of a full view high resolution panorama, we introduce a rotational mosaic representation, which includes the rotation parameters, the focal length and the principal point with each input image. A local registration algorithm is developed to quickly align two images exclusively from the image data. In order to reduce accumulated errors a global registration algorithm is performed to simultaneously minimize the misregistration between all overlapping pairs of images. By combining both registration techniques, we improve the quality of full view panoramic image mosaics. Finally we introduce a weighted blending algorithm to generate spherical or cylindrical panoramas. Furthermore we present an efficient visualization tool to display our produced high resolution panoramas. We developed a method to warp panoramas by utilizing the OpenGL graphic system to overcome the restriction of common panorama viewers, which are only allowing the visualization of small panoramas. The panoramic image is digitally warped on-the-fly to simulate camera panning and zooming. Walking through the virtual environment is currently accomplished by jumping to different panoramic points. The presented documentation system provides the creation as well as the efficient visualization of high resolution panoramic image mosaics to document important areas in urban environments.