Codec method and system for multi-channel three-dimensional audio

Abstract

The invention discloses an encoding and decoding method and system for multi-channel three-dimensional voice frequency. The encoding and decoding system comprises a time-frequency transform module, a sub-band division module, a sub-band energy calculation module, a transform module, a sub-band energy reducing module, a sub-band compositing module and a frequency-time transform module. At an encoding end, time-domain signals inputted into sound channels are transformed into frequency-domain signals, the frequency-domain signals of all the sound channels into sub-bands, and the sub-band energy is calculated; corresponding sub-band energy of the three adjacent sound channels is combined into sound channel units; the sub-band energy in the sound channel units is analyzed, and the transformational matrix is selected according to the analysis result; at a decoding end, the sound channel units are reduced through indexing the transformational matrix, the frequency-domain signals of all the sound channels are obtained, and the domain signals of all the sound channels are obtained through the frequency-time transformation, so that the reduction of the original sound channel signal is completed to the great extent, without distortion. The method and the system can achieve the redundant information removal among sound channels, have the characteristics of low complexity and high efficiency, and are suitable for direct broadcasting, communication and transmission requirements of the three-dimensional voice frequency.

Description

technical field [0001] The invention belongs to the field of encoding and decoding for multi-channel audio, in particular to a encoding and decoding method and system for multi-channel three-dimensional audio. Background technique [0002] With the great success of the 3D film and television market, 3D audio technology has received widespread attention and developed rapidly. Three-dimensional audio systems are increasingly being introduced into audio-related applications to replace traditional surround sound systems because they can provide audiences with better sound positioning and presence. Wave Field Synthesis (WFS), Ambisonics (holographic sound) and vector based amplitude panning (VBAP) are the three most well-developed multi-channel 3D audio theories. [0003] In the future, three-dimensional audio technology will gradually mature and replace the existing stereo and surround sound technologies. A major feature of current 3D audio systems is their large channel count...

AI Technical Summary

Problems solved by technology

In 2009, Hellerud used inter-channel predictive coding to remove redundant information between Ambisonics channels. This method has low algorithm delay, but high computational complexity.

The above model and parameter encoding method can provide a higher compression ratio, but in practical applications, audio encoders must take into account both algorithm complexity and encoding efficiency, and parameter encoding can only improve the encoding sound quality at low bit rates

Images