A mobile computing device that provides location information through directional sound is described herein. The mobile computing device includes a location detection system that provides location signals corresponding to a user location and a destination location, such as a vehicle location or a vertex of a predefined travel route, to a spatial audio generation system to define a spatial audio signal based on a direction from the user location to the destination location. The spatial audio signal is provided to an audio device of the mobile computing device that outputs the spatial audio signal as directional sound having a locus at the destination location.

3D audio virtualization within headphone-type sound reproduction devices, comprises: deriving an HRTF, comprising a PRTF, that includes acoustical effects due to pinnae and ear canals, and a remainder HRTF, that includes acoustical effects due to head, shoulders, torso and other body parts while excluding acoustical effects from pinnae and ear canals; wherein the remainder HRTF is electronically implemented and omits acoustical effects due to pinnae and ear canal effects; and wherein the PRTF is acoustically implemented and personalized to the user through use of two or more transducers positioned such that a front plane of the transducer, the front plane of the transducer's diaphragm, the transducer's mechanical center or the transducer's acoustical center point are 25 mm or more from a user's ear canal entrance, and/or oriented so the 0° axis of acoustical output is aligned with the acoustical output axes of typical external loudspeakers positioned in the acoustical far-field.

3D audio virtualization within headphone-type sound reproduction devices, comprises: deriving an HRTF, comprising a PRTF, that includes acoustical effects due to pinnae and ear canals, and a remainder HRTF, that includes acoustical effects due to head, shoulders, torso and other body parts while excluding acoustical effects from pinnae and ear canals; wherein the remainder HRTF is electronically implemented and omits acoustical effects due to pinnae and ear canal effects; and wherein the PRTF is acoustically implemented and personalized to the user through use of two or more transducers positioned such that a front plane of the transducer, the front plane of the transducer's diaphragm, the transducer's mechanical center or the transducer's acoustical center point are 25 mm or more from a user's ear canal entrance, and/or oriented so the 0° axis of acoustical output is aligned with the acoustical output axes of typical external loudspeakers positioned in the acoustical far-field.

In various applications, the system provides a method for processing audio signals, including: receiving, by a processor, a digital audio signal from a recorded audio file; analyzing, by the processor, the digital audio signal to identify pitch distortion caused by changes in momentary sound level; determining, by the processor, an amount of compensation of the audio signal to correct the identified pitch distortion; dynamically adjusting, by the processor, the digital audio signal by the compensation amount to correct the identified pitch distortion; and outputting, by the processor, the digital audio signal to an audio transducer device of a listener to improve a listening experience for the listener of the recorded audio file.

In various applications, the system provides a method for processing audio signals, including: receiving, by a processor, a digital audio signal from a recorded audio file; analyzing, by the processor, the digital audio signal to identify pitch distortion caused by changes in momentary sound level; determining, by the processor, an amount of compensation of the audio signal to correct the identified pitch distortion; dynamically adjusting, by the processor, the digital audio signal by the compensation amount to correct the identified pitch distortion; and outputting, by the processor, the digital audio signal to an audio transducer device of a listener to improve a listening experience for the listener of the recorded audio file.

A method and apparatus for reconstructing N audio channels from M audio channels is disclosed. The method includes receiving a bitstream containing an encoded audio signal representing the M audio channels and decoding the encoded audio signal to obtain a frequency domain representation of the M audio channels. The method further includes extracting a parameter from the bitstream and reconstructing at least one of the N audio channels using the parameter. The parameter represents an angle between two signals, at least one of which is included in the M audio channels.

A method and apparatus for reconstructing N audio channels from M audio channels is disclosed. The method includes receiving a bitstream containing an encoded audio signal representing the M audio channels and decoding the encoded audio signal to obtain a frequency domain representation of the M audio channels. The method further includes extracting a parameter from the bitstream and reconstructing at least one of the N audio channels using the parameter. The parameter represents an angle between two signals, at least one of which is included in the M audio channels.

A method for audio processing, the method comprising: determining at least one input audio object that includes an input audio object signal and an input audio object location, wherein the input audio object location includes a distance and a direction relative to a listener location; depending on the distance, applying a delay, a gain, and/or a spectral modification to the input audio object signal to produce a first dry signal; depending on the direction, panning the first dry signal to the locations of a plurality of speakers around the listener location to produce a second dry signal; depending on one or more predetermined room characteristics, generating an artificial reverberation signal from the input audio object signal; mixing the second dry signal and the artificial reverberation signal to produce a multichannel audio signal; and outputting each channel of the multichannel audio signal by one of the plurality of speakers.

A method for audio processing, the method comprising: determining at least one input audio object that includes an input audio object signal and an input audio object location, wherein the input audio object location includes a distance and a direction relative to a listener location; depending on the distance, applying a delay, a gain, and/or a spectral modification to the input audio object signal to produce a first dry signal; depending on the direction, panning the first dry signal to the locations of a plurality of speakers around the listener location to produce a second dry signal; depending on one or more predetermined room characteristics, generating an artificial reverberation signal from the input audio object signal; mixing the second dry signal and the artificial reverberation signal to produce a multichannel audio signal; and outputting each channel of the multichannel audio signal by one of the plurality of speakers.

A networked speaker system communicates using Li-Fi. The LEDs implementing the Li-Fi may also have modes in which they are used to map the walls of a room in which the speakers are located, detect the locations of speakers in the room, and detect and classify listeners in the room. Based on this, waveform analysis may be applied to input audio to establish equalization and delays that are optimal for the room geometry, speaker locations, and listener locations.