Shape retrieval with robustness against partial occlusion

Object shape features are powerful when used in similarity search-&-retrieval and object recognition because object shape is usually strongly linked to object functionality and identity. Many applications, including those concerned with visual object retrieval or indexing, are likely to use shape features. Those systems have to cope with scaling, rotation, deformation and partial occlusion of the objects to be described. The ISO standard MPEG-7 contains different shape descriptors; we focus especially on the region-shape descriptor. Since we have found the region-shape descriptor not to be very robust against partial occlusion, we propose a slightly changed feature extraction method, which is based on central-moments. Further, we compare our method with the original region-shape implementation and show that, by applying the proposed changes, the robustness of the region-shape descriptor against partial occlusions can be significantly increased.