LOW BITRATE AUDIO ENCODING/DECODING SCHEME HAVING CASCADED SWITCHES

摘要

An audio encoder has a first information sink oriented encoding branch, a second information source or SNR oriented encoding branch, and a switch for switching between the first encoding branch and the second encoding branch, wherein the second encoding branch has a converter into a specific domain different from the spectral domain, and wherein the second encoding branch furthermore has a specific domain coding branch, and a specific spectral domain coding branch, and an additional switch for switching between the specific domain coding branch and the specific spectral domain coding branch. An audio decoder has a first domain decoder, a second domain decoder for decoding a signal, and a third domain decoder and two cascaded switches for switching between the decoders.

主权项

1. Audio encoding apparatus for encoding an audio input signal, the audio input signal being in a first domain, comprising:
a first coding branch for encoding an audio signal using a first coding algorithm to acquire a first encoded signal; a second coding branch for encoding an audio signal using a second coding algorithm to acquire a second encoded signal, wherein the first coding algorithm is different from the second coding algorithm; and a first switch for switching between the first coding branch and the second coding branch so that, for a portion of the audio input signal, either the first encoded signal or the second encoded signal is in an encoder output signal, wherein the second coding branch comprises:
a converter for converting the audio signal into a second domain different from the first domain,a first processing branch for processing an audio signal in the second domain to acquire a first processed signal;a second processing branch for converting a signal into a third domain different from the first domain and the second domain and for processing the signal in the third domain to acquire a second processed signal; anda second switch for switching between the first processing branch and the second processing branch so that, for a portion of the audio signal input into the second coding branch, either the first processed signal or the second processed signal is in the second encoded signal.