Panasonic Intellectual Property Corporation of America

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Huan Zhou

Takeshi Norimatsu

Tomokazu Ishikawa

Kok Seng Chong

Haishan Zhong

Zhong Hai Shan

Takeshi Narimatsu

To provide a bandwidth extension method which allows reduction of computation amount in bandwidth extension and suppression of deterioration of quality in the bandwidth to be extended. In the bandwidth extension method: a low frequency bandwidth signal is transformed into a QMF domain to generate a first low frequency QMF spectrum; pitch-shifted signals are generated by applying different shifting factors on the low frequency bandwidth signal; a high frequency QMF spectrum is generated by time-stretching the pitch-shifted signals in the QMF domain; the high frequency QMF spectrum is modified; and the modified high frequency QMF spectrum is combined with the first low frequency QMF spectrum.

Bandwidth extension method, bandwidth extension apparatus, program, integrated circuit, and audio decoding apparatus

A new hybrid audio decoder and a new hybrid audio encoder having block switching for speech signals and audio signals are provided. Currently, very low bitrate audio coding methods for speech and audio signals are proposed. These audio coding methods cause very long delays. Generally, in coding an audio signal, an algorithm delay tends to be long to achieve higher frequency resolution. In coding a speech signal, the delay needs to be reduced because the speech signal is used for telecommunication. To balance fine coding quality for speech and audio input signals with very low bitrate, a combination of a low delay filter bank like AAC-ELD and a CELP coding method is provided.

Hybrid audio encoder and hybrid audio decoder which perform coding or decoding while switching between different codecs

A coding apparatus which suppresses an extreme increase in a bit rate, includes: a downmixing and coding unit () that downmixes audio signals that have been provided, to reduce the number of channels to be fewer than the number of the provided audio signals, and to code the downmix signals; an object parameter extracting unit () that extracts parameters indicating correlation between the audio signals; and a multiplexing circuit () that multiplexes the extracted parameters with the generated downmix coded signals. The object parameter extracting unit () includes: an object classifying unit () that classifies each of the provided audio signals into a predetermined one of types based on audio characteristics; and an object parameter extracting circuit () that extracts parameters using a temporal granularity and a frequency granularity each of which is determined for a corresponding one of the types.

Coding apparatus and decoding apparatus

To provide an audio signal processing apparatus which can perform, with low operation amount, audio signal processing that is either time stretch and/or compression processing or frequency modulation processing. The audio signal processing apparatus is intended to transform an input audio signal sequence using a predetermined adjustment factor. The audio signal processing apparatus includes a filter bank () which transforms the input audio signal sequence into Quadrature Mirror Filter (QMF) coefficients using a filter for Quadrature Mirror Filter analysis (a QMF analysis filter) and an adjusting unit () which adjusts the QMF coefficients based on a predetermined adjustment factor.

Audio signal processing apparatus, audio coding apparatus, and audio decoding apparatus

Provided is an encoding device () including: a pitch contour analysis unit () which detects information, a dynamic time-warping unit () which generates, based on the information, pitch change ratios (Tw_ratio in FIG.) within a range () including a range () of the pitch change ratios corresponding to absolute pitch differences of 42 cents or larger; a first lossless coding unit () which codes the generated pitch parameters (); a time-warping unit () which shifts a pitch of a signal according to the information; and a second encoding unit which codes a signal () obtained by the shifting.

Audio encoding device, decoding device, method, circuit, and program

An object decoding unit receives a plurality of pieces of coded acoustic information coded on an object basis and decodes the received coded acoustic information on an object basis to generate object signals. A rendering unit positions, for each acoustic signal resulting from synthesizing the object signals, a virtual sound source of each of the object signals resulting from the object-based decoding, in a listening space, and priority information indicating a priority of the acoustic signal is multiplexed with the coded acoustic information. The rendering unit determines, with reference to the priority indicated in the priority information or the number of object signals included in the acoustic signal, a size of an area of the listening space which is allocated to the acoustic signal, and positions, within the area, the virtual sound source of each of the object signals included in the acoustic signal.

Decoding device, coding and decoding device, and decoding method

A combination device () according to the present invention includes: a detection unit () that detects active coded bitstreams that are effective coded bitstreams from a plurality of coded bitstreams () within a predetermined time period; a first combining unit () that combines, from a plurality of downmix sub-streams () included in the coded bitstreams (), only downmix sub-streams () included in the active coded bitstreams so as to generate a combined downmix sub-stream (); and a second combining unit () that combines, from a plurality of parameter sub-streams () included in the coded bitstreams (), only parameter sub-streams () included In the active coded bitstreams so as to generate a combined parameter sub-stream ().

Combination device, telecommunication system, and combining method

The delay in a multi-channel audio coding apparatus and a multi-channel audio decoding apparatus is reduced. The audio coding apparatus includes: a downmix signal generating unit that generates, in a time domain, a first downmix signal that is one of a 1-channel audio signal and a 2-channel audio signal from an input multi-channel audio signal; a downmix signal coding unit that codes the first downmix signal; a first t-f converting unit that converts the input multi-channel audio signal into a multi-channel audio signal in a frequency domain; and a spatial information calculating unit that generates spatial information for generating a multi-channel audio signal from a downmix signal.

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Singapore, Singapore

Huan Zhou