Point Pair Features Based Object Detection and Pose Estimation Revisited

We present a revised pipe-line of the existing 3D object detection and pose estimation framework [ 10] based on point pair feature matching. This framework proposed to represent 3D target object using self-similar point pairs, and then matching such model to 3D scene using efficient Hough-like voting scheme operating on the reduced pose parameter space. Even though this work produces great results and motivated a large number of extensions, it had some general shortcoming like relatively high dimensionality of the search space, sensitivity in establishing 3D correspondences, having performance drops in presence of many outliers and low density surfaces. In this paper, we explain and address these drawbacks and propose new solutions within the existing framework. In particular, we propose to couple the object detection with a coarse-to-fine segmentation, where each segment is subject to disjoint pose estimation. During matching, we apply a weighted Hough voting and an interpolated recovery of pose parameters. Finally, all the generated hypothesis are tested via an occlusion-aware ranking and sorted. We argue that such a combined pipeline simultaneously boosts the detection rate and reduces the complexity, while improving the accuracy of the resulting pose. Thanks to such enhanced pose retrieval, our verification doesn't necessitate ICP and thus achieves better compromise of speed vs accuracy. We demonstrate our method on existing datasets as well as on our scenes. We conclude that via the new pipe-line, point pair features can now be used in more challenging scenarios.