“…All these properties make local descriptor algorithms be widely applied in many fields, such as, content-based large-scale retrieval [2], video analysis, copy detection, object recognition, photo tourism, and 3D reconstruction [3]. A good local descriptor algorithm should have following characteristics: no necessity of pre-segmenting images [4], high repeatability of feature detector, low dimension of feature descriptor, robustness to partial occlusion, and invariance against image transformations, such as, illumination, rotation, scale, blur, and affine.…”