Abstract: In general, techniques are described for psychoacoustic audio coding of ambisonic audio data. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may store the bitstream that includes an encoded audio object and a corresponding spatial component that defines spatial characteristics of the encoded foreground audio signal. The encoded foreground audio signal may include a coded gain and a coded shape. The one or more processors may perform a gain and shape synthesis with respect to the coded gain and the coded shape to obtain a foreground audio signal, and reconstruct, based on the foreground audio signal and the spatial component, the ambisonic audio data.

Abstract: In general, various aspects of the techniques described in this disclosure are directed to performing psychoacoustic audio coding based on operating conditions. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may be configured to store the encoded scene-based audio data. The one or more processors may be configured to obtain an operating condition of the device for decoding the encoded scene-based audio data and perform, based on the operating condition, psychoacoustic audio decoding with respect to the encoded scene-based audio data to obtain ambisonic transport format audio data. The one or more processors may also be configured to perform spatial audio decoding with respect to the ambisonic transport format audio data to obtain scene-based audio data.

Abstract: In general, techniques are described for quantizing spatial components based on bit allocations determined for psychoacoustic audio coding. A device comprising a memory and one or more processors may perform the techniques. The memory may store a bitstream including an encoded foreground audio signal and a corresponding quantized spatial component. The one or more processors may perform psychoacoustic audio decoding with respect to the encoded foreground audio signal to obtain a foreground audio signal, and determine, when performing the psychoacoustic audio decoding, a first bit allocation for the encoded foreground audio signal. The one or more processors may also determine, based on the first bit allocation, a second bit allocation, and dequantize, based on the second bit allocation, the quantized spatial component to obtain a spatial component. The one or more processors may reconstruct, based on the foreground audio signal and the spatial component, scene-based audio data.

Abstract: In general, techniques are described by which to code scaled spatial components. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may store a bitstream including an encoded foreground audio signal and a corresponding quantized spatial component. The one or more processors may perform psychoacoustic audio decoding with respect to the encoded foreground audio signal to obtain a foreground audio signal, and determine, when performing psychoacoustic audio decoding, a bit allocation for the encoded foreground audio signal. The one or more processors may dequantize the quantized spatial component to obtain a scaled spatial component, and descale, based on the bit allocation, the scaled spatial component to obtain a spatial component. The one or more processors may reconstruct, based on the foreground audio signal and the spatial component, scene-based audio data.

Abstract: In general, techniques are described by which to correlate scene-based audio data for psychoacoustic audio coding. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may store a bitstream including a plurality of encoded correlated components of a soundfield represented by scene-based audio data. The one or more processors may perform psychoacoustic audio decoding with respect to one or more of the plurality of encoded correlated components to obtain a plurality of correlated components, and obtain, from the bitstream, an indication representative of how the one or more of the plurality of correlated components were reordered in the bitstream. The one or more processors may reorder, based on the indication, the plurality of correlated components to obtain a plurality of reordered components, and reconstruct, based on the plurality of reordered components, the scene-based audio data.

Abstract: In general, techniques are described by which to provide priority information for higher order ambisonic (HOA) audio data. A device comprising a memory and a processor may perform the techniques. The memory stores HOA coefficients of the HOA audio data, the HOA coefficients representative of a soundfield. The processor may decompose the HOA coefficients into a sound component and a corresponding spatial component, the corresponding spatial component defining shape, width, and directions of the sound component, and the corresponding spatial component defined in a spherical harmonic domain. The processor may also determine, based on one or more of the sound component and the corresponding spatial component, priority information indicative of a priority of the sound component relative to other sound components of the soundfield, and specify, in a data object representative of a compressed version of the HOA audio data, the sound component and the priority information.

Abstract: In general, techniques are described for rendering metadata to control user movement based audio rendering. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may be configured to store audio data representative of a soundfield. The one or more processors may be coupled to the memory, and configured to obtain rendering metadata indicative of controls for enabling or disabling adaptations, based on an indication of a movement of a user of the device, of a renderer used to render audio data representative of a soundfield, specify, in a bitstream representative of the audio data, the rendering metadata, and output the bitstream.

Abstract: In general, techniques are described for performing codebook selection when coding vectors decomposed from higher-order ambisonic coefficients. A device comprising a memory and a processor may perform the techniques. The memory may be configured to store a plurality of codebooks to use when performing vector dequantization with respect to a vector quantized spatial component of a soundfield. The vector quantized spatial component may be obtained through application of a decomposition to a plurality of higher order ambisonic coefficients. The processor may be configured to select one of the plurality of codebooks.

Abstract: An example audio decoding device includes processing circuitry and a memory device coupled to the processing circuitry. The processing circuitry is configured to receive, in a bitstream, encoded representations of audio objects of a three-dimensional (3D) soundfield, to receive metadata associated with the bitstream, to obtain, from the received metadata, one or more transmission factors associated with one or more of the audio objects, and to apply the transmission factors to the one or more audio objects to obtain parallax-adjusted audio objects of the 3D soundfield. The memory device is configured to store at least a portion of the received bitstream, the received metadata, or the parallax-adjusted audio objects of the 3D soundfield.

Abstract: A device for processing coded audio is disclosed. The device is configured to store an audio object and audio object metadata associated with the audio object. The audio object metadata includes frequency dependent beam pattern metadata. The device may apply, based on the frequency dependent beam pattern metadata, a renderer to the audio object to obtain one or more speaker feeds and output the one or more speaker feeds.

Abstract: In one example, a device for retrieving audio data includes one or more processors configured to receive availability data representative of a plurality of available adaptation sets, the available adaptation sets including a scene-based audio adaptation set and one or more object-based audio adaptation sets, receive selection data identifying which of the scene-based audio adaptation set and the one or more object-based audio adaptation sets are to be retrieved, and provide instruction data to a streaming client to cause the streaming client to retrieve data for each of the adaptation sets identified by the selection data, and a memory configured to store the retrieved data for the audio adaptation sets.

Abstract: An example audio decoding device includes processing circuitry and a memory device coupled to the processing circuitry. The processing circuitry is configured to receive, in a bitstream, encoded representations of audio objects of a three-dimensional (3D) soundfield, to receive metadata associated with the bitstream, to obtain, from the received metadata, one or more transmission factors associated with one or more of the audio objects, and to apply the transmission factors to the one or more audio objects to obtain parallax-adjusted audio objects of the 3D soundfield. The memory device is configured to store at least a portion of the received bitstream, the received metadata, or the parallax-adjusted audio objects of the 3D soundfield.

Abstract: In general, techniques are described by which to provide priority information for higher order ambisonic (HOA) audio data. A device comprising a memory and a processor may perform the techniques. The memory stores HOA coefficients of the HOA audio data, the HOA coefficients representative of a soundfield. The processor may decompose the HOA coefficients into a sound component and a corresponding spatial component, the corresponding spatial component defining shape, width, and directions of the sound component, and the corresponding spatial component defined in a spherical harmonic domain. The processor may also determine, based on one or more of the sound component and the corresponding spatial component, priority information indicative of a priority of the sound component relative to other sound components of the soundfield, and specify, in a data object representative of a compressed version of the HOA audio data, the sound component and the priority information.

Abstract: A device and method for backward compatibility for virtual reality (VR), mixed reality (MR), augmented reality (AR), computer vision, and graphics systems. The device and method enable rendering audio data with more degrees of freedom on devices that support fewer degrees of freedom. The device includes memory configured to store audio data representative of a soundfield captured at a plurality of capture locations, metadata that enables the audio data to be rendered to support N degrees of freedom, and adaptation metadata that enables the audio data to be rendered to support M degrees of freedom. The device also includes one or more processors coupled to the memory, and configured to adapt, based on the adaptation metadata, the audio data to provide the M degrees of freedom, and generate speaker feeds based on the adapted audio data.

Abstract: In general, techniques are described for obtaining audio rendering information from a bitstream. A method of rendering audio data includes receiving, at an interface of a device, an encoded audio bitstream, storing, to a memory of the device, encoded audio data of the encoded audio bitstream, parsing, by one or more processors of the device, a portion of the encoded audio data stored to the memory to select a renderer for the encoded audio data, the selected renderer comprising one of an object-based renderer or an ambisonic renderer, rendering, by the one or more processors of the device, the encoded audio data using the selected renderer to generate one or more rendered speaker feeds, and outputting, by one or more loudspeakers of the device, the one or more rendered speaker feeds.

Abstract: In general, techniques are described for modeling occlusions when rendering audio data. A device comprising a memory and one or more processors may perform the techniques. The memory may store audio data representative of a soundfield. The one or more processors may obtain occlusion metadata representative of an occlusion within the soundfield in terms of propagation of sound through the occlusion, the occlusion separating the soundfield into two or more sound spaces. The one or more processors may obtain a location of the device, and obtain, based on the occlusion metadata and the location, a renderer by which to render the audio data into one or more speaker feeds that account for propagation of the sound in one of the two or more sound spaces in which the device resides. The one or more processors may apply the renderer to the audio data to generate the speaker feeds.

Abstract: One or more processors may obtain a first distance between a first audio zone of the two or more audio zones associated with the one or more interest points within the first audio zone, and a first device position of a device, obtain a second distance between a second audio zone of the two or more audio zones associated with the one or more interest points within the second audio zone, and the first device position of the device, and obtain an updated first distance and updated second distance after movement of the device has changed from the first device position to a second device position. The one or more processor(s) may independently control the first audio zone and the second audio zone, such that the audio data within the first audio zone and the second audio zone are adjusted based on the updated first distance and updated second distance.

Abstract: Disclosed are techniques and devices which include a memory configured to store audio data within a first audio zone, or a second audio zone in a layered soundfield. The memory is coupled to one or more processors and the memory is configured to store the audio data in the first audio zone and the second audio data in the layered soundfield. The one or more processors are configured to receive an interaction command to control the audio data in the first audio zone and the second audio zone in the layered soundfield, and generate one or more indicators that the interaction command was received to control the audio data, in the first audio zone or the second audio zone of the layered soundfield.

Abstract: In general, techniques are described by which to embed enhanced audio transports in backward compatible bitstreams. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may store the backward compatible bitstream, which conforms to a legacy transport format. The processor(s) may obtain, from the backward compatible bitstream, legacy audio data that conforms to a legacy audio format, and obtain, from the backward compatible bitstream, extended audio data that enhances the legacy audio data. The processor(s) may also obtain, based on the legacy audio data and the extended audio data, enhanced audio data that conforms to an enhanced audio format, and output the enhanced audio data to one or more speakers.

Abstract: In general, techniques are described by which to synchronize enhanced audio transports with backward compatible audio transports. A device comprising a memory and one or more processors may be configured to perform the techniques. The memory may store a backward compatible bitstream conforming to a legacy transport format. The processor may obtain, from the backward compatible bitstream, a first audio transport stream, and obtain, from the backward compatible bitstream, a second audio transport stream. The processor(s) may also obtain, from the backward compatible bitstream, indications representative of synchronization information for the first audio transport stream and the second audio transport stream. The processor(s) may synchronize, based on the indications, the first audio transport stream and the second audio transport to obtain synchronized audio data stream.