Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Corporation of America

Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Panasonic Intellectual Property Management Co., Ltd.

Nippon Telegraph and Telephone Corporation

Pansonic Corporation

Toshiyuki Morii

Kazutoshi Yasunaga

Hiroyuki Ehara

Tomofumi Yamanashi

Kaoru Sato

Masahiro Oshikiri

Taisuke Watanabe

Koji Yoshida

Yutaka Murakami

Masayuki Orihashi

Kiyotaka Kobayashi

Kaoru Satoh

Yusuke Hiwasaki

Kazunori Mano

Katsunori Daimou

Provided are a vector quantization device, a voice coding device, a vector quantization method, and a voice coding method which enable a reduction in the calculation amount of voice codec without deterioration of voice quality. In the vector quantization device, a first reference vector calculation unit () calculates a first reference vector by multiplying a target vector (x) by an auditory weighting LPC synthesis filter (H), and a second reference vector calculation unit () calculates a second reference vector by multiplying an element of the first reference vector by a filter having a high pass characteristic. A polarity preliminary selection unit () generates a polar vector by disposing a unit pulse having a positive or negative polarity, which is selected on the basis of the polarity of an element of the second reference vector, in the position of said element.

Vector quantization of algebraic codebook with high-pass characteristic for polarity selection

A band power computation device with which the amount of calculation required to compute channel power is reduced, and with which it is possible to obtain channel power with the same precision as when the channel power is obtained from the entire input signal. With this device, a subspace extraction unit () extracts a portion of the input signal. An FFT unit () performs a Fourier transformation on the extracted signal, generating a spectrum signal. A power computation unit () computes the channel power for each frequency from the spectrum signal. A power generation unit () expands the channel power to the same channel power as the channel power computed from the input signal, and smoothes the expanded channel power by performing a calculation sequentially from the highest frequency to the lowest frequency, said calculation using the expanded channel power and a prescribed constant.

Band power computation device and band power computation method

This encoding device () is provided with: a CELP encoding unit () that decodes CELP encoded data resulting from CELP encoding an input signal, generating a CELP decoded signal; a transform encoding unit () that generates a decoded signal spectrum by decoding transform encoded data resulting from using the spectrum of the input signal and the suppression spectrum of suppressing using a first suppression factor to transform encode the amplitude of the spectrum of the CELP decoded signal, and that outputs an index of the transform encoded frequency component; a pulse index recording unit () that forms and records an array using the index; and a CELP component suppression unit () that uses a second suppression factor and the array to suppress the amplitude of the spectrum resulting from adding the decoded signal spectrum and the suppression spectrum.

Encoding device and encoding method

Provided are a coding device, a communication processing device, and a coding method, whereby processing operation load (computational load) is significantly reduced for a configuration which computes either frame energy or sub-frame energy of an input signal, using auto-correlation operations, without causing a decline in the precision of either the frame energy or the sub-frame energy. In a coding device (), a sub-frame energy computation unit () computes the sub-frame energy by substituting the sum of input signal auto-correlation operations in a first range with the sum of auto-correlation operations in a second range which differs at least partially from the first range.

Coding device, communication processing device, and coding method

A pulse location search device () is equipped with: a first search unit () that obtains a first location where a first pulse is located by conducting a first preliminary selection with respect to a first candidate group, and conducting a first search; a second search unit () that obtains a second location where a second pulse is located by using the first location and conducting a second search with respect to all of the location candidates of a second candidate group of locations where the second pulse is located; and a third search unit () that obtains a third location where the first pulse is located by using the second location and conducting a second preliminary selection with respect to the first candidate group, and conducting a third search with respect to the result of the second preliminary selection.

Fixed codebook searching by closed-loop search using multiplexed loop

A coding apparatus is provided that improves the quality of a decoded signal in a hierarchical coding (scalable coding) scheme in which a coding target band is selected in each hierarchy (layer). The coding apparatus includes a first layer coding section that selects a first quantization target band of inputted spectrum and generates first layer coded information including first band information of the selected band. An adder generates a first layer difference spectrum using a first decoded signal generated using the first layer coded information and the inputted spectrum. A second layer coding section generates second layer coded information including second band information of the selected band, wherein first layer coding section determines a method of quantizing the gain of the inputted spectrum from a plurality of candidates based on the first band information and second band information.

Encoder apparatus, decoder apparatus, and related methods that use plural coding layers

A quantization device and quantization method are provided that reduce coding distortion with a small degree of calculation and achieve adequate coding performance thereby. A multistage vector quantization unit treats a number of candidates N that are designated prior to operation in the first-stage vector quantization unit, decrements the number of candidates by one beginning with the second-stage vector quantization unit and continuing with each stage thereafter. If the number of candidates is three or less, the multistage vector quantization unit assesses the quantization distortion at each stage, treating the number of candidates at the following stage as a predetermined value P if the quantization distortion is greater than a prescribed threshold, and treating the number of candidates at the following stage as a value Q that is less than the predetermined value P if the quantization distortion is less than or equal to the predetermined threshold.

Quantization device and quantization method

Disclosed is an encoding device that improves the quality of a decoded signal in a hierarchical coding (scalable coding) method, wherein a band to be quantized is selected for every level (layer). The encoding device () is equipped with a second layer encoding unit () that selects a first band to be quantized of a first input signal from among a plurality of sub-bands, and that generates second layer encoding information containing first band information of said band; a second layer decoding unit () that generates a first decoded signal using the second layer encoding information; an addition unit () that generates a second input signal using the first input signal and the first decoded signal; and a third layer encoding unit () that selects a second band to be quantized of the second input signal using the first decoded signal, and that generates third layer encoding information.

Encoding device, decoding device, and methods therefor

Disclosed is an encoding device which can accurately specify a band having a large error among all the bands by using a small calculation amount. A first position identifier uses a first layer error conversion coefficient indicating an error of a decoding signal for an input signal so as to search for a band having a large error in a relatively wide bandwidth in all the bands of the input signal and generates first position information indicating the identified band. A second position identifier searches for a target frequency band having a large error in a relatively narrow bandwidth in the band identified by the first position identifier and generates second position information indicating the identified target frequency band. An encoder encodes a first layer decoding error conversion coefficient contained in the target frequency band.

Encoding device, decoding device, and method thereof for secifying a band of a great error

Encoding device, decoding device, and method thereof for specifying a band of a great error

An encoding apparatus includes a first layer encoder that encodes an input signal, a first layer decoder that decodes the first layer encoded data, a weighting filter that filters a first layer error signal to acquire a weighted first layer error signal, a first layer error transform coefficient calculator that transforms the weighted first layer error signal into a frequency domain, and a second layer encoder that encodes the first layer error transform coefficient. The second layer encoder includes a first shape vector encoder that refers the first layer error transform coefficient to generate a first shape vector and first shape encoded information. A target gain calculator calculates a target gain using the first layer error transform coefficient and the first shape vector, a gain vector generator generates a gain vector, and a gain vector encoder encodes the gain vector to acquire gain encoded information.

Encoding apparatus, decoding apparatus, encoding method and decoding method

An encoding apparatus includes a first layer encoder that encodes a signal, a first layer decoder that decodes first layer encoded data, a first layer error transform coefficient calculator that transforms a first layer error signal into a frequency domain and a second layer encoder that encodes the first layer error transform coefficient to acquire second layer encoded data. The second layer encoder includes a band determiner that determines a band to be encoded by the second layer encoder, and a first shape vector encoder that refers the first layer error transform coefficient included in the band to generate a first shape vector and first shape encoded information, a target gain calculator calculates target gain per subband, a gain vector generator generates a gain vector using a plurality of target gains, and a gain vector encoder encodes the gain vector to acquire gain encoded information.

There is disclosed an encoder apparatus whereby, when a band expanding technique for encoding, based on the spectral data of a lower frequency portion, the spectral data of a higher frequency portion is applied to a lower layer in a hierarchical encoding/decoding system, an efficient encoding can be performed in an upper layer as well, thereby improving the decoded-signal quality. In an encoder apparatus (), a second layer decoder unit () calculates a spectrum (differential spectrum), which is to be encoded in a third layer encoder unit () that is an upper layer of the second layer decoder unit (), by applying such an ideal gain (first gain parameter a) that minimizes the energy of the differential spectrum.

Growing community of inventors

Kanagawa, Japan

Toshiyuki Morii