H.263+: Video coding at low bit rates

In this tutorial paper, we discuss the ITU-T H.263+ (or H,263 Version 2) lo w-bit-rate video coding standard. We first describe, briefly, the H,263 sta ndard including its optional modes. We then address the 12 new negotiable m odes of H.263+, Next, we present experimental results for these modes, base d on our public-domain implementation (see our Web site at http://spmg.ece. ubc.ca). Tradeoffs among compression performance, complexity, and memory re quirements for the H,263+ optional modes are discussed. Finally, results fo r mode combinations are presented.