Abstract: This signal processing device is provided with a detection circuit for detecting a temporal variation in a time difference between channels of a stereo signal, and a control circuit for controlling the degree of smoothing of an inter-channel cross correlation function on the basis of the temporal variation in the time difference between the channels.

Abstract: A coding apparatus includes: a first coding circuit that codes an input signal selectively using coding in a time domain or a frequency domain according to the characteristic of the input signal in a core layer; and a second coding circuit that codes an error in coding by the first coding circuit using a coding method corresponding to the domain type of coding used in the core layer in an extension layer for the core layer.

Abstract: An encoding device is provided with: a quantizing circuit which generates quantization parameters including first information on a vector quantization codebook, and second information on code vectors included in the codebook; and a control circuit which employs the second number of bits based on the difference between the first number of bits available for encoding of a sub-vector in the vector quantization, and the number of bits for the sub-vector quantization parameters, to control encoding of the first information with respect to the sub-vector.

Abstract: A method that generates binaural headphone playback signals given multiple audio source signals with an associated metadata and binaural room impulse response (BRIR) database, wherein the audio source signals are channel-based, object-based, or a mixture of both channel-based and object-based signals. The method includes parameterizing BRIR to be used for rendering, dividing each audio source signal to be rendered into a number of blocks and frames, and averaging the parameterized BRIR sequences. The method also includes downmixing the divided audio source signals using the diffuse blocks of BRIRs, and performing late reverberation processing on the downmixed version of the previous blocks of the audio source signals.

Abstract: A communication method supports Enhanced Voice Services (EVS) codec performed by a communication terminal apparatus. The method includes performing negotiation to use an EVS codec for communication between a communication terminal apparatus and a counterpart terminal, using an IP multimedia subsystem (IMS) signaling including one of a session description protocol (SDP) offer and an SDP answer, and performing negotiation to specify one or more audio-bandwidths of input signals in Hertz (Hz) or kilohertz (kHz) for the EVS codec. In a communication session after the codec negotiation session, the processor causes the receiver to receive a signaling for changing an audio-bandwidth of an input signal to the EVS codec from a network node, changes the audio-bandwidth of the input signal to the EVS codec to another audio-bandwidth without changing the EVS codec based on the signaling, and causes the transmitter to transmit encoded data in the changed audio-bandwidth.

Abstract: This encoding device is provided with a control circuit that, on the basis of information relating to the capability to convert the signal form of a sound signal in a decoding device for decoding encoded data of the sound signal, controls the conversion of the signal form of the sound signal, and an encoding circuit that encodes the sound signal in accordance to the conversion control.

Abstract: This quantization scale factor determination device is provided with a correction circuit which corrects an initial value of a quantization scale factor on the basis of whether or not an audio signal spectrum is sparse, and a search circuit which searches for a quantization scale factor on the basis of the initial value.

Abstract: This encoding device is able to encode an S signal efficiently in MS prediction encoding. An M signal encoding unit generates first encoding information by encoding a sum signal indicating a sum of a left channel signal and a right channel signal that constitute a stereo signal. An energy difference calculation unit calculates a prediction parameter for predicting a difference signal indicating a difference between the left channel signal and the right channel signal by using a parameter regarding an energy difference between the left channel signal and the right channel signal. An entropy encoding unit generates second encoding information by encoding the prediction parameter.

Abstract: An audio signal coding apparatus includes a time-frequency transformer that outputs sub-band spectra from an input signal; a sub-band energy quantizer; a tonality calculator that analyzes tonality of the sub-band spectra; a bit allocator that selects a second sub-band on which quantization is performed by a second quantizer on the basis of the analysis result of the tonality and quantized sub-band energy, and determines a first number of bits to be allocated to a first sub-band on which quantization is performed by a first quantizer; the first quantizer that performs first coding using the first number of bits; the second quantizer that performs coding using a second coding method; and a multiplexer.

Abstract: In the acoustic object extraction device, beam forming processing units generate a first acoustic signal by beam forming in an arrival direction of a signal from an acoustic object with respect to a microphone array and generate a second acoustic signal by beam forming in an arrival direction of a signal from the acoustic object with respect to a microphone array, and a common component extraction unit extracts, on the basis of a similarity between the spectrum of the first acoustic signal and the spectrum of the second acoustic signal and from the first acoustic signal and the second acoustic signal, a signal containing a common component corresponding to the acoustic object. The common component extraction unit divides the spectrums of the first acoustic signal and the second acoustic signal into a plurality of frequency sections and calculates a similarity for each of the frequency sections.

Abstract: A method that generates binaural headphone playback signals given multiple audio source signals with an associated metadata and binaural room impulse response (BRIR) database, wherein the audio source signals are channel-based, object-based, or a mixture of both channel-based and object-based signals. The method includes parameterizing BRIR to be used for rendering, dividing each audio source signal to be rendered into a number of blocks and frames, and averaging the parameterized BRIR sequences. The method also includes downmixing the divided audio source signals using the diffuse blocks of BRIRs, and performing late reverberation processing on the downmixed version of the previous blocks of the audio source signals.

Abstract: A method generates binaural headphone playback signals given multiple audio source signals with associated metadata and a binaural room impulse response (BRIR) database, where the audio source signals can be channel-based, object-based, or a mixture of both signals. The method groups the audio source signals according to positions of the audio sources, divides BRIR into blocks and frames, where the BRIR is divided into a direct block and diffuse blocks, and divides each audio source signal into blocks and frames, wherein the source signal is divided into a current block and previous blocks, and the current block is further divided into the frames. The method further averages, for each of previous frames of the source signals, the divided BRIR identified with the grouping result by downmixing the previous frames of the source signals according to the grouping result, and performs a convolution with the downmixed previous frame.

Abstract: An encoding device according to the disclosure includes a first encoder, which in operation, encodes a low-band signal from a voice or audio input signal to generate a first encoded signal; a decoder, which in operation, decodes the first encoded signal to generate a low-band decoded signal; a second encoder, which in operation, encodes, on the basis of the low-band decoded signal, a high-band signal comprising a band from the voice or audio input signal, the band being higher than that of the low-band signal to generate a high-band encoded signal; an energy calculator, which in operation, calculates an energy of the voice or audio input signal for each subband of a plurality of subbands of the voice or audio input signal to acquire a calculated energy for each subband of the plurality of subbands of the voice or audio input signal, quantizes the calculated energy for each subband of the plurality of subbands of the voice or audio input signal to acquire a quantized band energy for each subband of the plurali

Abstract: Provided is a direction of arrival estimation device wherein: a calculation circuit calculates a frequency weighting factor for each of a plurality of frequency components of signals recorded in a microphone array, on the basis of the differences among unit vectors indicating the directions of the sound sources of each of the plurality of frequency components; and an estimation circuit estimates the direction of arrival of a signal from the sound source, on the basis of the frequency weighting factors.

Abstract: In an encoder, a signal analysis unit performs signal analysis on an L channel signal and an R channel signal that constitute a stereo signal and generates a parameter used to determine a coding mode for each of an L channel and an R channel. A DMA stereo encoding unit encodes the L channel signal and the R channel signal by using a coding mode common to the L channel signal and the R channel signal. At this time, the DMA stereo encoding unit determines the common coding mode by selecting, out of the L channel and the R channel, the one that has a lower ratio of energy of an environmental sound component to the entire energy of the channel and using the parameter of the selected channel.

Abstract: A decoding device includes: a separating unit separating first encoded data, a spectrum including a low-band spectrum of audio signals having been encoded, and second encoded data, a high-band spectrum of a higher band having been encoded, based on the first encoded data; a first decoding unit decoding the first encoded data and generating a first decoded spectrum; a first amplitude normalizer dividing amplitude of the first decoded spectrum into sub-bands, normalizing the spectrum of each sub-band by the largest amplitude of the first decoded spectrum within each sub-band, and generating a normalized spectrum; an addition unit adding noise spectrum to the normalized spectrum and generating a noise-added normalized spectrum; a second decoding unit decoding the second encoded data using the noise-added normalized spectrum, and generating a second noise-added spectrum; and a converter performing time-frequency conversion regarding a spectrum coupled based on the first decoded spectrum and second noise-added spe

Abstract: An encoding device according to the disclosure includes a first encoding unit that generates a first encoded signal in which a low-band signal having a frequency lower than or equal to a predetermined frequency from a voice or audio input signal is encoded, and a low-band decoded signal; a second encoding unit that encodes, on the basis of the low-band decoded signal, a high-band signal having a band higher than that of the low-band signal to generate a high-band encoded signal; and a first multiplexing unit that multiplexes the first encoded signal and the high-band encoded signal to generate and output an encoded signal. The second encoding unit calculates an energy ratio between a high-band noise component, which is a noise component of the high-band signal, and a high-band non-tonal component of a high-band decoded signal generated from the low-band decoded signal and outputs the ratio as the high-band encoded signal.

Abstract: An inter-channel correlation calculation unit calculates an inter-channel correlation between a left channel and a right channel by using a left channel signal and a right channel signal that constitute a stereo signal. A DMA stereo encoding unit and a DM stereo encoding unit encode the left channel signal and the right channel signal by using a common coding mode when the inter-channel correlation is greater than a threshold value, and individually encode the left channel signal and the right channel signal by using a coding mode determined for each of the left channel signal and the right channel signal when the inter-channel correlation is less than or equal to the threshold value.

Abstract: This encoding device is able to encode an S signal efficiently in MS prediction encoding. An M signal encoding unit generates first encoding information by encoding a sum signal indicating a sum of a left channel signal and a right channel signal that constitute a stereo signal. An energy difference calculation unit calculates a prediction parameter for predicting a difference signal indicating a difference between the left channel signal and the right channel signal by using a parameter regarding an energy difference between the left channel signal and the right channel signal. An entropy encoding unit generates second encoding information by encoding the prediction parameter.

Abstract: In the acoustic object extraction device, beam forming processing units generate a first acoustic signal by beam forming in an arrival direction of a signal from an acoustic object with respect to a microphone array and generate a second acoustic signal by beam forming in an arrival direction of a signal from the acoustic object with respect to a microphone array, and a common component extraction unit extracts, on the basis of a similarity between the spectrum of the first acoustic signal and the spectrum of the second acoustic signal and from the first acoustic signal and the second acoustic signal, a signal containing a common component corresponding to the acoustic object. The common component extraction unit divides the spectrums of the first acoustic signal and the second acoustic signal into a plurality of frequency sections and calculates a similarity for each of the frequency sections.