Bit allocation method, encoding device and decoding device

Abstract

The invention provides a bit allocation method, comprising the following steps of: carrying out quantization encoding on spectrum envelops of each subband of a low-frequency signal and on spectrum envelops of each subband of a high-frequency signal; carrying out absolute hearing threshold weighing on a quantization value of each spectrum envelop; carrying out perception sequencing on all of the subbands according to the quantization values of the spectrum envelops after the absolute hearing threshold weighing; and allocating bit sources according to the sequence of the perception sequencing. The invention also provides an encoder, an encoding method, a bit allocation method, a decoder and a decoding method. The invention can ensure the reasonability of the perception sequencing so that the bit sources can be self-adaptively allocatedto the subband with important perception. Meanwhile, the invention effectively reduces the calculation complexity, and has the advantages of little realization time delay and little source consumption.

Description

technical field [0001] The present invention relates to codec technology, in particular to bit allocation technology. Background technique [0002] The sub-band coding technology is one of the commonly used coding and decoding technologies at present. Audio signals can be divided into multiple frequency bands from low to high in the frequency domain. A frequency band is called a sub-band, and subsequent encoding, decoding, and other work are performed on the basis of sub-bands. In embedded audio coding, the 0-7k frequency domain range is called wideband (WB, Wideband), and the 7-14k frequency domain range is called super wideband (SWB, Super Wideband). In the process of encoding and decoding, broadband signals and ultra-wideband signals need to be quantized and coded, wherein, compared to ultra-wideband signals, broadband signals are low-frequency signals, and ultra-wideband signals are high-frequency signals compared to broadband signals. The coder's bit rate (Bit Rate) d...

AI Technical Summary

Problems solved by technology

[0011] The inventors of the present invention found that in the process of implementing the present invention: in the bit allocation scheme 1, the limited bit resources cannot be reasonably allocated to the perceptually more important sub-bands in all sub-bands when the code rate is high, so that the coding The quality of the audio signal output by the

In the bit allocation scheme 2, the obtained perceptual ranking is unreasonable, and the quality balance of the high-frequency signal and low-frequency signal output by the encoder cannot be guaranteed, which in turn affects the overall quality of the encoder

Bit allocation scheme 3 has the problems of high computational complexity, large resource occupation, and large algorithm delay

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