Three-dimensional ground truth reconstruction using 2D ISAR imagery

Since ISAR (inverse synthetic aperture radar) can convey information which may not be obtainable by other imaging means, research on applying ISAR to battle field awareness has been intensive. One highly desirable application of ISAR imagery is to reconstruct 3D ground truth, which provides depth information to enhance target recognition and tracking. This paper proposes a stereo vision approach to reconstruct 3D ground truth using ISAR imagery. The proposed approach includes three steps: multiscale feature extraction, stereo matching, and surface interpolation. The multiscale feature extraction is accomplished using a wavelet edge detector, which can smooth the signal and reduce noise at different levels. Stereo matching is implemented using an inverse filtering method, which provides the sparse disparity map for 3D depth information using extracted features. The surface interpolation takes the sparse data generated from stereo matching and interpolate to the dense surface data as the final output. Issues regarding where and how the stereo techniques used for ISAR differ from the ones for video images will be addressed. The initial test shows encouraging results. Future research directions and potential commercial applications are also discussed.