A technique wherein the number and position of a quantization parameter
node is determined in response to the quantization parameters and a
preselected error. The size of scene graph and the corresponding amount
of memory required to store the scene graph can be reduced by selective
placement of quantization parameter nodes in a scene graph. The scene
graph is traversed depth first to establish an order and then traversed
in reverse. At each node, a calculation relating to (1) the relative cost
of inserting a quantization parameter node and (2) the relative savings
that result from insertion of a quantization node is performed.
Quantization parameter nodes are selectively placed in response to a
result of these calculations. The maximum degree of acceptable error
value is chosen for each quantization type. This error value limits the
number of quantization parameter nodes that can be placed in a scene
graph.