Motion vector prediction with reference frame consideration

In this paper, we introduce a new motion vector prediction method that could be used within multiple picture reference codecs, such as the H.264 (MPEG-4 AVC) video coding standard. Our method considers for each candidate motion vector the temporal distance of its corresponding reference picture compared to the current one for the generation of the predictor motion vector. This allows for more accurate motion vector prediction, and better exploitation of the temporal correlation that may exist within a video sequence. Furthermore, we also introduce a modification to the SKIP motion vector macroblock mode, according to which not only the motion vectors but also the reference indices are adaptively generated. Simulation results suggest that our proposed methods, combined with an improved Rate Distortion optimization strategy, if implemented within the existing H.264 codec, can allow for a considerable performance improvement of up to 8.6% bitrate reduction compared to the current H.264 standard.