Our work focuses on the encoding of two-dimensional (2-D) graphics animated cartoons with MPEG-4. This stems from a need to stop encoding cartoons as videos and to start using methods more adapted to animated 2-D vector graphics sequences. We expected this could be an efficient coding with good versatility for various types of terminals. First, we present some technical specification for such cartoons. Next, we give an overview of MPEG-4 BIFS encoding methods. Then, we analyze how to optimize the use of these methods; some of our proposals could be useful for 2-D graphics applications other than animated cartoon. Last, we show some results with significantly better encoding efficiency over simple BIFS encoding.