An audio processing apparatus comprises a receiver (705) which receives audio data including audio components and render configuration data including audio transducer position data for a set of audio transducers (703). A renderer (707) generating audio transducer signals for the set of audio transducers from the audio data. The renderer (7010) is capable of rendering audio components in accordance with a plurality of rendering modes. A render controller (709) selects the rendering modes for the renderer (707) from the plurality of rendering modes based on the audio transducer position data. The renderer (707) can employ different rendering modes for different subsets of the set of audio transducers the render controller (709) can independently select rendering modes for each of the different subsets of the set of audio transducers (703). The render controller (709) can select the rendering mode for a first audio transducer of the set of audio transducers (703) in response to a position of the first audio transducer relative to a predetermined position for the audio transducer. The approach may provide improved adaptation, e.g. to scenarios where most speakers are at desired positions whereas a subset deviate from the desired position(s).

The invention discloses rendering sound field signals, such as Higher-Order Ambisonics (HOA), for arbitrary loudspeaker setups, where the rendering results in highly improved localization properties and is energy preserving. This is obtained by rendering an audio sound field representation for arbitrary spatial loudspeaker setups and/or by a decoder that decodes based on a decode matrix (D). The decode matrix (D) is based on smoothing and scaling of a first decode matrix {circumflex over (D)} with smoothing coefficients. The first decode matrix {circumflex over (D)} is based on a mix matrix G and a mode matrix {tilde over (Ψ)}, where the mix matrix G was determined based on L speakers and positions of a spherical modelling grid related to a HOA order N, and the mode matrix {tilde over (Ψ)} was determined based on the spherical modelling grid and the HOA order N.

A voice output corresponding to a fixed position of a wide viewing angle image is easily obtained. A transmission unit configured to transmit spatial voice data and information regarding a predetermined number of registered viewpoints is included. For example, the spatial voice data is data of scene-based audio. Then, for example, the data of the scene-based audio is each component of an HoA format. For example, the information regarding a viewpoint includes information regarding an azimuth angle (azimuth information) and an elevation angle (elevation angle information) that indicate a position of this viewpoint. For example, the data of the scene-based audio and the information regarding the predetermined number of registered viewpoints are transmitted with being included in a packet of object audio.

The invention improves HOA sound field representation compression and decompression. A decoder decodes compressed dominant directional signals and compressed residual component signals so as to provide decompressed dominant directional signals and decompressed time domain signals representing a residual HOA component in a spatial domain. A re-correlator re-correlates the decompressed time domain signals to obtain a corresponding reduced-order residual HOA component. A processor determines a decompressed residual HOA component based on the corresponding reduced-order residual HOA component, and determines predicted directional signals based on at least a parameter. The processor is further configured to determine an HOA sound field representation based on the decompressed dominant directional signals, the predicted directional signals, and the decompressed residual HOA component.

An example device includes a memory configured to store audio data and location data associated with a plurality of audio streams and one or more processors coupled to the memory. The one or more processors are configured to obtain a first location of a first audio stream that includes an audio source and obtain a second location of a second audio stream that includes the audio source. The one or more processors are configured to generate direction vectors originating at the first location and the second location, based on a location of the audio source and the first location, and the location of the audio source and the second location, respectively. The one or more processors are also configured to determine parameters that describe a vector field based on the first direction vector and the second direction vector.

The present technology relates to a signal processing device, a signal processing method, and a program that enable more efficient sound reproduction.

A signal processing device includes an order determination unit that determines an order for limiting an operation amount of an operation related to a rotation matrix corresponding to head rotation of a listener, a rotation operation unit that rotates a head-related transfer function of a spherical harmonic domain by the operation in which the rotation matrix is limited by the order, and a synthesis unit that generates a headphone drive signal by synthesizing the head-related transfer function after rotation obtained by the operation with a sound signal in the spherical harmonic domain. The present technology can be applied to an audio processing device.

Systems and methods for rendering spatial audio in accordance with embodiments of the invention are illustrated. One embodiment includes a spatial audio system, including a primary network connected speaker, including a plurality of sets of drivers, where each set of drivers is oriented in a different direction, a processor system, memory containing an audio player application, wherein the audio player application configures the processor system to obtain an audio source stream from an audio source via the network interface, spatially encode the audio source, decode the spatially encoded audio source to obtain driver inputs for the individual drivers in the plurality of sets of drivers, where the driver inputs cause the drivers to generate directional audio.

Provided is a sound image localization device capable of flexibly controlling directivity with a short calculation time. A sound image localization device that reflects, on a reflector 50, a sound signal radiated from a speaker array 40 arranged with a plurality of speakers SP.sub.1 to SP.sub.Q on a straight line to localize a sound image includes an expansion coefficient calculation unit 10 configured to analytically calculate expansion coefficients by performing a spherical harmonic function expansion on a window function representing desired directivity, a filter coefficient generation unit 20 configured to convert the expansion coefficients into filter coefficients corresponding to each of the speakers SP.sub.1 to SP.sub.Q, and a speaker drive unit 30 configured to generate a speaker drive signal for driving each of the speakers SP.sub.1 to SP.sub.Q by convolving the filter coefficients in a voice signal.

A method for interpolating a sound field captured by a plurality of N microphones each outputting the encoded sound field in a form including at least one captured pressure and an associated pressure gradient vector. Such a method includes an interpolation of the sound field at an interpolation position outputting an interpolated encoded sound field as a linear combination of the N encoded sound fields each weighted by a corresponding weighting factor. The interpolation includes an estimation of the N weighting factors at least from: the interpolation position; a position of each of the N microphones; the N pressures captured by the N microphones; and an estimated power of the sound field at the interpolation position.

A virtual reproduction signal generation unit generates a virtual reproduction signal based on a sound pickup signal of a stereophonic sound at a listening position in a compartment, assuming that virtual speakers are respectively located at portions of Np positions in a vehicle, the virtual reproduction signal causing the virtual speakers of the Np positions to reproduce the stereophonic sound. A virtual prediction signal generation unit generates a virtual prediction signal based on the virtual reproduction signal and an information representing a change of acoustic characteristics when at least part of the portions of the Np positions is changed, the virtual prediction signal causing the virtual speakers of the Np positions to output a predicted sound at the listening position. An output signal generation unit generates an output signal based on the virtual prediction signal, the output signal causing speakers of a plurality of positions to output the predicted sound.