Abstract:
A device includes an encoder and a transmitter. The encoder is configured to generate a first high-band portion of a first signal based on a left signal and a right signal. The encoder is also configured to generate a set of adjustment gain parameters based on a high-band non-reference signal. The high-band non-reference signal corresponds to one of a left high-band portion of the left signal or a right high-band portion of the right signal as a high-band non-reference signal. The transmitter is configured to transmit information corresponding to the first high-band portion of the first signal. The transmitter is also configured to transmit the set of adjustment gain parameters corresponding to the high-band non-reference signal.
Abstract:
A device for signal processing includes a memory and a processor. The memory is configured to store a parameter associated with a bandwidth-extended audio stream. The processor is configured to select a plurality of non-linear processing functions based at least in part on a value of the parameter. The processor is also configured to generate a high-band excitation signal based on the plurality of non-linear processing functions.
Abstract:
Systems and methods of performing blind bandwidth extension are disclosed. In an embodiment, a method includes receiving, at a decoder of a speech vocoder, a set of low-band parameters as part of a narrowband bitstream. The set of low-band parameters are received from an encoder of the speech vocoder. The method also includes predicting a set of high-band parameters based on the set of low-band parameters.
Abstract:
Systems and methods of performing blind bandwidth extension are disclosed. In an embodiment, a method includes determining, based on a set of low-band parameters of an audio signal, a first set of high-band parameters and a second set of high-band parameters. The method further includes generating a predicted set of high-band parameters based on a weighted combination of the first set of high-band parameters and the second set of high-band parameters.
Abstract:
The present document relates to audio encoding and decoding. In particular, the present document relates to audio coding schemes which make use of high frequency reconstruction (HFR) methods. A system configured to determine a master scale factor band table of a highband signal (105) of an audio signal is described. The highband signal (105) is to be generated from a lowband signal (101) of the audio signal using a high frequency reconstruction (HFR) scheme. The master scale factor band table is indicative of a frequency resolution of a spectral envelope of the highband signal (105).
Abstract:
Audio signal bandwidth extension is performed on a narrow bandwidth signal received from a remote source over the audio communication network. The narrow band signal bandwidth is extended such that the bandwidth is greater than that of the audio communication network. The signal is extended by synthesizing an audio signal having spectral values within an extended bandwidth from synthetic components. The synthetic components may be generated using parameters derived from original narrowband audio signal. The audio signal may be synthesized in the form of an excitation signal and vocal tract envelope. The excitation signal and vocal tract may be extended independently. In various embodiments, excitation components may be derived from constrained synthesis using a constraint filter with nulls in regions where the extension is desired.
Abstract:
본 발명은 음성 또는 오디오 신호의 신호 대역을 확장하는 방법 및 장치에 관한 것으로서, 본 발명에 따른 대역 확장 방법은 입력 시그널을 MDCT(Modified Discrete Cosine Transform) 하여 제1 변환 신호를 생성하는 단계, 상기 제1 변환 신호를 기반으로 제2 변환 신호 및 제3 변환 신호를 생성하는 단계, 상기 제1 변환 신호, 제2 변환 신호, 제3 변환 신호로부터 각각의 정규 성분 및 에너지 성분을 생성하는 단계, 상기 각각의 정규 신호로부터 확장 정규 성분을 생성하고, 상기 각각의 에너지 성분으로부터 확장 에너지 성분을 생성하는 단계, 상기 확장 정규 성분과 상기 확장 에너지 성분을 기반으로 확장 변환 신호를 생성하는 단계 및 상기 확장 변환 신호를 IMDCT(Inverse MDCT)하는 단계를 포함한다.
Abstract:
IIn accordance with an embodiment, a method of decoding an encoded audio bitstream at a decoder includes receiving the audio bitstream, decoding a low band bitstream (207) of the audio bitstream to get low band coefficients (209) in a frequency domain, and copying a plurality of the low band coefficients to a high frequency band location to generate high band coefficients (213). The method further includes processing the high band coefficients (213) to form processed high band coefficients (214). Processing includes modifying an energy envelope of the high band coefficients (213) by multiplying modification gains to flatten or smooth the high band coefficients (213), and applying a received spectral envelope decoded from the received audio bitstream to the high band coefficients (213). The low band coefficients (209) and the processed high band coefficients (214) are then inverse-transformed to the time domain to obtain a time domain output signal (215).