Apparatus and method of processing an audio signal, utilizing unique offsets associated with each coded-coefficients

A method of processing an audio signal, the method comprising:

• calculating a prediction coefficient value for a block of digital audio data;
• first entropy coding the prediction coefficient value for transmission based on an entropy parameter table, the entropy parameter table being selected from a plurality of entropy parameter tables, each entropy parameter table including offset values and entropy parameters, each offset having a corresponding entropy parameter, wherein each offset is associated with a coded-coefficient and is different for each coded-coefficient if the coded-coefficient is less than 20;
• adding table index information into the digital audio data, the table index information identifying the entropy parameter table;
• converting the coded-coefficient values into linear predictive coding (LPC) coefficients;
• predicting current data samples in the block based on the LPC coefficients;
• obtaining a prediction residual based on the predicted current data sample and a current data sample;
• second entropy coding the prediction residual based on another entropy parameter;
• and multiplexing the entropy coded prediction residual with the entropy coded prediction coefficient value.

An apparatus for decoding an audio signal, the apparatus comprising:

• a demultiplexer configured to demultiplex a prediction residual and a prediction coefficient value from a received audio signal, and to demultiplex table index information from the received audio signal, the table index information identifying a table to select from a plurality of entropy parameter tables;
• a first entropy decoder configured to decode the prediction coefficient value by selecting an entropy parameter table from the plurality of entropy parameter tables based on the table index information and entropy decoding the prediction coefficient value based on the selected entropy parameter table, each entropy parameter table including offset values and entropy parameters, each offset having a corresponding entropy parameter, wherein each offset is associated with a coded-coefficient and is different for each coded-coefficient if the coded-coefficient is less than 20;
• a coefficient converting part configured to convert the coded-coefficient values into linear predictive coding (LPC) coefficients;
• a predictor configured to predict current data samples in the block based on the LPC coefficients;
• a second entropy decoder configured to decode the prediction residual based on another entropy parameter;
• and an adder configured to add the predicted current data samples to the prediction residual from the second entropy decoder.

An apparatus for encoding an audio signal, the apparatus comprising:

• a buffer configured to store a block of digital audio data;
• a coefficient estimator configured to calculate a set of prediction coefficient values for the block of digital audio data;
• a first entropy encoder configured to first entropy code the prediction coefficient values for transmission based on a selected entropy parameter table, and to add table index information into the digital audio data, the table index information identifying the selected entropy parameter table from a plurality of entropy parameter tables, each entropy parameter table including offset values and entropy parameters, each offset having a corresponding entropy parameter, wherein each offset is associated with a coded-coefficient and is different for each coded-coefficient if the coded-coefficient is less than 20;
• a coefficient converter configured to convert the coded-coefficient values into linear predictive coding (LPC) coefficients;
• a predictor configured to predict current data samples in the block based on the LPC coefficients;
• a subtracter configured to obtain a prediction residual based on the predicted current data sample and a current data sample;
• a second entropy encoder configured to encode the predicted residual based on another entropy parameter;
• and a multiplexer configured to multiplex the entropy coded prediction residual with the entropy coded prediction coefficient values.