A video coding system that codes video objects as scalable video object layers.
Data of each video object may be segregated into one or more layers. A base layer
contains sufficient information to decode a basic representation of the video object.
Enhancement layers contain supplementary data regarding the video object that,
if decoded, enhance the basic representation obtained from the base layer. The
present invention thus provides a coding scheme suitable for use with decoders
of varying processing power. A simple decoder may decode only the base layer of
video objects to obtain the basic representation. However, more powerful decoders
may decode the base layer data of video objects and additional enhancement layer
data to obtain improved decoded output. The coding scheme supports enhancement
of both the spatial resolution and the temporal resolution of video objects.