Automatic Pose Estimation Using Contour Information from X-Ray Images
An automatic approach to model-based pose estimation is presented that only uses given, segmented contours in X-ray images. The pose estimation based on Fourier Descriptors is extended to an arbitrary, calibrated stereo setup and eliminates the need for a manually given initialization. To further refine the pose, local and global optimization schemes that minimize the distance between the segmentation and the projected object over the six pose parameters are compared. Experiments show that a sampling-based optimization outperforms gradient-based methods and the sampling can be further improved to fit the given imaging setup and the object of interest. Simulated data shows that the pose can be estimated nearly perfect in stereo setups and yields highly accurate results on single-view setups. Clinical data supports these findings.
KeywordsPose estimation Fourier descriptors Simulated Annealing
We would like to thank the Laboratory for Biomechanics and Biomaterials, Dept. of Orthopaedics, Hannover Medical School for providing the models and the clinical data used in the evaluation.
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