Extending the sGLOH descriptor

This paper proposes an extension of the sGLOH keypoint descriptor which improves its robustness and discriminability. The sGLOH descriptor can handle discrete rotations by a cyclic shift of its element thanks to its circular structure but its performances can decrease when the keypoint relative rotation is in between two sGLOH discrete rotations. The proposed extension couples together two sGLOH descriptor of the same patch with different rotations in order to cope with this issue and it can be also applied straightly to the sCOr and sGOr matching strategies of sGLOH. Experimental results show a consistent improvement of the descriptor discriminability while different setups can be used to reduce the running time according to the desidered task.