A SYSTEM AND METHOD FOR EFFICIENT NOISE INJECTION FOR LOW BITRATE AUDIO COMPRESSION

摘要

The present invention provides a device, method (400, 500), and system (100) of noise injection to maximize compressed audio quality while enabling bitrate scalability. It includes at least one of an encoder and a decoder. The encoder includes a zero detection unit, coupled to receive a frequency domain quantized signal, for determining a control signal that indicates whether noise injection is implemented and a normalization computation unit, coupled to receive at least unquantized signal values and the control signal, for determining a normalization term in accordance with the control signal. The decoder includes a zero detection unit, coupled to receive a frequency domain quantized signal, for determining a control signal that indicates when noise injection is active and a noise generation and normalization unit, coupled to receive a normalization term and the control signal, for generating, normalizing, and injecting a predetermined noise signal where indicated by the control signal.