The paper describes a three-layer video coder based on spatiotemporal scalability and data partitioning. The base layer represents video sequences with reduced spatial and temporal resolution. Decoding of a middle layer gives full resolution images but with lower quality as compared to those obtained from the enhancement layer also. The bitrate overhead measured relative to the single layer MPEG-2 bitstream varies about 5% – 25% for progressive television test sequences. The base layer is fully MPEG-2 compatible and the whole structure exhibits high level of compatibility with individual building blocks of MPEG-2 coders. The paper reports experimental results that prove useful properties of the coder proposed.