Patent ID: 6693645
Filing Date: 2004-02-17
Classification: H04N

Abstract:
A method of processing a data file, the method comprising:determining a range of values assumed by node parameters in a hierarchy of nodes wherein a grouping node at the top of the hierarchy is followed by one or more child nodes, wherein the nodes are specified by the data file; determining a quantization parameter that indicates a desired number of bits with which to represent the value range of one or more of the node parameters for the nodes in the hierarchy; examining each node in the hierarchy and determining if a change in quantization parameter for a node is desirable and, if so, determining a quantization parameter value with the desired change and inserting it into the hierarchy at the node, thereby producing a quantized hierarchy; examining the quantization parameter at each node of the quantized hierarchy and determining if one or more quantization parameters at a child node of the node being examined can be subsumed under the examined node quantization parameter and, if so, deleting the child node quantization parameter from the quantized hierarchy; and wherein the quantization parameters are used to determine the number of bits used to represent data parameters during data compression.