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: A three-dimensional audio processing method for use in reproducing three-dimensional audio using an augmented reality (AR) device includes: obtaining change information indicating change occurring in a space in which the AR device is located when content that includes a sound is being output in the AR device; selecting, based on the change information, one or more audio processes among a plurality of audio processes for rendering sound information indicating the sound; executing only the one or more audio processes selected among the plurality of audio processes; and rendering the sound information based on a first processing result of each of the one or more audio processes executed.

Abstract: An information processing method includes: obtaining a position of a user within the three-dimensional sound field; determining a virtual boundary that includes two or more lattice points surrounding the user, based on the position of the user which has been obtained, the two or more lattice points being among a plurality of lattice points set at predetermined intervals within the three-dimensional sound reading field; the propagation characteristics of the sound from the sound source to the two or more lattice points included in the virtual boundary determined; calculating transfer functions of the sound from the two or more lattice points included in the virtual boundary determined to the position of the user; and generating the output sound signal by processing the sound information using the propagation characteristics read and the transfer functions calculated.

Abstract: A sound signal processing method includes: obtaining a sound signal; determining, for each of a plurality of sound processes executed in a pipeline, whether to execute the sound process on the sound signal, based on priority information indicating a priority associated with the sound signal; and executing each sound process determined to be executed in the determining, on the sound signal.

Abstract: In an acoustic processing method, (i) sound information related to a sound including a predetermined sound and (ii) metadata including information related to a space in which the predetermined sound is reproduced are obtained; based on the sound information and the metadata, sound image localization enhancement processing of generating a first sound signal expressing a sound including a sound image localization enhancement reflected sound for localization as a sound arriving from a predetermined direction is performed; based on the sound information and the metadata, acoustic processing of generating a second sound signal expressing a sound including a sound other than a direct sound that reaches a user directly from a sound source object is performed; and an output sound signal obtained by compositing the first sound signal and the second sound signal is output.

Abstract: An acoustic processing method includes: obtaining (i) sound information related to a sound including a predetermined sound and (ii) metadata including information related to a space in which the predetermined sound is reproduced; performing, based on the sound information and the metadata, acoustic processing of generating a sound signal expressing a sound including an early reflection that reaches a user after a direct sound that reaches the user directly from a sound source object; and outputting an output sound signal including the sound signal. The acoustic processing includes: determining parameters for generating the early reflection, the parameters including a position, in the space, of a virtual sound source object that generates the early reflection; and generating the early reflection based on the parameters determined. The parameters include at least a parameter that varies over time according to a predetermined condition.

Abstract: An encoding device comprising: a quantization circuit that generates a quantization parameter that includes information about a vector quantization codebook; and a control circuit that sets the number of available bits according to conditions for encoding based on the difference between the number of bits available for encoding of the target sub-vector and the number of bits for the quantization parameter of the target sub-vector.

Abstract: Each of one or more audio objects includes: sound data of a sound emitted from an object that corresponds to the audio object; and metadata that includes position information indicating a position of the object in a virtual sound space. A sound signal processing device includes: a selector that selects an audio object as a conversion target from among the one or more audio objects; and an fluctuation imparter that converts the audio object selected as the conversion target to impart, to the audio object selected, a fluctuation effect of fluctuating a sound emitted from an object that corresponds to the audio object converted when the sound signal is reproduced. The selector does not select an audio object that corresponds to an object whose position is moving in the virtual sound space based on a transition over time of the position information included in the metadata.

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: An encoding apparatus includes: a quantization circuit that generates a quantization parameter including first information related to a codebook of vector quantization and second information related to code vectors included in the codebook; and a control circuit that determines which one of first encoding of the first information for the target sub-vector and second encoding of a second number of bits based on the difference between an allocated number of bits for vector quantization and the number of bits of the quantization parameter is to be executed, in accordance with the number of bits available for encoding sub-vectors including at least a target sub-vector among a plurality of sub-vectors in the vector quantization.

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: This encoding device comprises: a downmix circuit that switches mixing processing according to the characteristic of an input stereo signal to generate either a first stereo signal or a second stereo signal obtained by mixing processing of a left channel signal and a right channel signal; a first encoding circuit that encodes the first stereo signal; and a second encoding circuit that encodes two signals included in the second stereo signal. The second encoding circuit performs monaural encoding on the basis of the encoding mode of the first encoding circuit in a first section in which switching from the first stereo signal to the second stereo signal is performed and/or a second section in which switching from the second stereo signal to the first stereo signal is performed.

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.