Encoding and decoding method and device

An encoding device, comprising:

• a first encoding unit configured to encode each sample of an input signal to generate an encoded signal of a core layer;
• a second encoding unit configured to compare residuals of all or a part of the samples of the input signal with encoding thresholds, wherein the residuals are generated by core layer encoding, and perform encoding according to comparison results to generate an encoded signal of an enhancement layer;
• and
• a generating unit configured to write the encoded signal of the core layer generated by the first encoding unit and the encoded signal of the enhancement layer generated by the second encoding unit into a bitstream to generate an encoded signal of the input signal.

A computer-readable storage medium, comprising computer program codes which when executed by a computer processor cause the computer processor to execute the steps of:

• encoding each sample of an input signal to generate an encoded signal of a core layer;
• comparing residuals of all or a part of the samples of the input signal with encoding thresholds, wherein the residuals are generated by core layer encoding, and performing encoding according to comparison results to generate an encoded signal of an enhancement layer;
• and
• writing the encoded signal of the core layer and the encoded signal of the enhancement layer into a bitstream to generate an encoded signal of the input signal.