Method and apparatus for adaptive entropy encoding/decoding of quantized transform coefficients in a video compression system

DETAILED DESCRIPTION The present invention is a method and apparatus for adaptive entropy encoding/decoding of a plurality of quantized transform coefficients in a video/image compression system.
For encoding, first, a predetermined number of quantized transform coefficients are received in a predetermined order, giving a generally decreasing average power.
Then the quantized transform coefficients are parsed into a plurality of coefficient groups.
When the last coefficient group comprises all zero quantized coefficients, it is discarded.
The coefficient groups are then converted into a plurality of parameter sets in the predetermined order.
A current parameter set is obtained from the parameter sets in the reverse order of the predetermined order.
A current entropy encoder is selected adaptively based on the previously selected entropy encoder and the previous parameter set.
The current parameter set is encoded by the current entropy encoder to provide entropy encoded information bits.