Motion Hooks for the Multiview Extension of HEVC

MV-HEVC refers to the multiview extension of High Efficiency Video Coding (HEVC). At the time of writing, MV-HEVC was being developed by the Joint Collaborative Team on 3D Video Coding Extension Development (JCT-3V) of International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) Moving Picture Experts Group and ITU-T VCEG. Before HEVC itself was technically finalized in January 2013, the development of MV-HEVC had already started and it was decided that MV-HEVC would only contain high-level syntax changes compared with HEVC, i.e., no changes to block-level processes, to enable the reuse of the first-generation HEVC decoder hardware as is for constructing an MV-HEVC decoder with only firmware changes corresponding to the high-level syntax part of the codec. Consequently, any block-level process that is not necessary for HEVC itself but on the other hand is useful for MV-HEVC can only be enabled through so-called hooks. Motion hooks refer to techniques that do not have a significant impact on the HEVC single-view version 1 codec and can mainly improve MV-HEVC. This paper presents techniques for efficient MV-HEVC coding by introducing hooks into the HEVC design to accommodate inter-view prediction in MV-HEVC. These hooks relate to motion prediction, hence named motion hooks. Some of the motion hooks developed by the authors have been adopted into HEVC during its finalization. Simulation results show that the proposed motion hooks provide on average 4% of bitrate reduction for the views coded with inter-view prediction.