This paper describes novel motion mapping algorithms aimed for low-complexity MPEG-2 to AVC transcoding. The proposed algorithms efficiently map incoming MPEG-2 motion vectors to outgoing AVC motion vectors regardless of the block sizes that the motion vectors correspond to. Extensive simulation results show that our proposed transcoder incorporating the proposed algorithms achieves very good rate-distortion performance with low complexity. Compared with the cascaded decoder-encoder solution, the proposed approach could achieve similar coding efficiency while significantly reduce the complexity. IEEE International Symposium on Circuits and Systems, May 2007 This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of M...