Abstract: Embodiments of systems and methods are described for providing backwards compatibility for legacy devices that are unable to natively render non-channel based audio objects. These systems and methods can also be beneficially used to produce a reduced set of audio objects for compatible object-based decoders with low computing resources.

Abstract: Embodiments of systems and methods are described for providing backwards compatibility for legacy devices that are unable to natively render non-channel based audio objects. These systems and methods can also be beneficially used to produce a reduced set of audio objects for compatible object-based decoders with low computing resources.

Abstract: A method of adjusting a loudness of an audio signal may include receiving an electronic audio signal and using one or more processors to process at least one channel of the audio signal to determine a loudness of a portion of the audio signal. This processing may include processing the channel with a plurality of approximation filters that can approximate a plurality of auditory filters that further approximate a human hearing system. In addition, the method may include computing at least one gain based at least in part on the determined loudness to cause a loudness of the audio signal to remain substantially constant for a period of time. Moreover, the method may include applying the gain to the electronic audio signal.

Abstract: An adaptive audio system can be implemented in a communication device. The adaptive audio system can enhance voice in an audio signal received by the communication device to increase intelligibility of the voice. The audio system can adapt the audio enhancement based at least in part on levels of environmental content, such as noise, that are received by the communication device. For higher levels of environmental content, for example, the audio system might apply the audio enhancement more aggressively. Additionally, the adaptive audio system can detect substantially periodic content in the environmental content. The adaptive audio system can further adapt the audio enhancement responsive to the environmental content.

Abstract: A method for processing audio signals can include receiving left and right front audio signals, where the left and right front audio signals including information about front spatial position of sound sources relative to a listener. The method can also include receiving left and right rear audio signals, where the left and right rear audio signals include information about rear spatial position of sound sources relative to a listener. In addition, the method can include applying at least one front perspective filter to each of the left and right front audio signals to yield filtered left and right front output signals, where the left and right front output signals each drive a front speaker.

Abstract: A system and method for enhancement and management of streaming audio is disclosed. In one embodiment, the system provides a client-side decoder that is compatible with numerous audio formats, so that a user can enjoy relatively high-quality audio from various sources, even from sources that do not provide multi-channel or high-quality audio data. The system and method also include a management system for managing and controlling the use of licensed signal processing software to further enhance an audio stream. In one embodiment, the management system is used to manage a signal processing module that provides psychoacoustic audio processing to create a wider soundstage, an acoustic correction process to increase the perceived height and clarity of the audio image, and bass enhancement processing to create the perception of low bass from the small speakers or headphones typically used with multi-media systems and portable audio players.

Abstract: Systems and methods for audio signal processing are disclosed, where a discrete number of simple digital filters are generated for particular portions of an audio frequency range. Studies have shown that certain frequency ranges are particularly important for human ears' location-discriminating capability, while other ranges are generally ignored. Head-Related Transfer Functions (HRTFs) are examples response functions that characterize how ears perceive sound positioned at different locations. By selecting one or more “location-critical” portions of such response functions, one can construct simple filters that can be used to simulate heating where location-discriminating capability is substantially maintained. Because the filters can be simple, they can be implemented in devices having limited computing power and resources to provide location-discrimination responses that form the basis for many desirable audio effects.

Abstract: A system and method for enhancement and management of streaming audio is disclosed. In one embodiment, the system provides a client-side decoder that is compatible with numerous audio formats, so that a user can enjoy relatively high-quality audio from various sources, even from sources that do not provide multi-channel or high-quality audio data. The system and method also include a management system for managing and controlling the use of licensed signal processing software to further enhance an audio stream. In one embodiment, the management system is used to manage a signal processing module that provides psychoacoustic audio processing to create a wider soundstage, an acoustic correction process to increase the perceived height and clarity of the audio image, and bass enhancement processing to create the perception of low bass from the small speakers or headphones typically used with multi-media systems and portable audio players.

Abstract: Various embodiments of systems and methods for reducing audio noise are disclosed. One or more sound components such as noise and network tone can be detected based on power spectrum obtained from a time-domain signal. Results of such detection can be used to make decisions in determination of an adjustment spectrum that can be applied to the power spectrum. The adjusted spectrum can be transformed back into a time-domain signal that substantially removes undesirable noise(s) and/or accounts for known sound components such as the network tone.

Abstract: An acoustic correction apparatus processes a pair of left and right input signals to compensate for spatial distortion as a function of frequency when said input signals are reproduced through loudspeakers in a sound system. The sound-energy of the left and right input signals is separated and corrected in a first low-frequency range and a second high-frequency range. The resultant signals are recombined to create image-corrected audio signals having a desired sound-pressure response when reproduced by the loudspeakers in the sound system. The desired sound-pressure response creates an apparent sound image location with respect to a listener. The image-corrected signals can also be spatially-enhanced to broaden the apparent sound image and improve the low frequency characteristics of the sound when played on small loudspeakers.

Abstract: A system can be provided for increasing loudness of an audio signal to present a perceived loudness to a listener that is greater than a loudness provided natively by a loudspeaker. The system can include one or more of the following: a frequency suppressor, a loudness adjuster, an equalizer, and a distortion control module. The frequency suppressor can increase headroom in the audio signal by filtering out low and/or high frequencies. The loudness adjuster can calculate a loudness of the audio signal and apply a gain to the audio signal to increase the loudness. The equalizer can further increase headroom by attenuating portions of a passband of the loudspeaker's frequency response. The distortion control module can induce partial harmonic distortion in the audio signal to further increase loudness.

Abstract: Systems and methods for providing object-oriented audio are described. Audio objects can be created by associating sound sources with attributes of those sound sources, such as location, velocity, directivity, and the like. Audio objects can be used in place of or in addition to channels to distribute sound, for example, by streaming the audio objects over a network to a client device. The objects can define their locations in space with associated two or three dimensional coordinates. The objects can be adaptively streamed to the client device based on available network or client device resources. A renderer on the client device can use the attributes of the objects to determine how to render the objects. The renderer can further adapt the playback of the objects based on information about a rendering environment of the client device. Various examples of audio object creation techniques are also described.

Abstract: Systems and methods for providing object-oriented audio are described. Audio objects can be created by associating sound sources with attributes of those sound sources, such as location, velocity, directivity, and the like. Audio objects can be used in place of or in addition to channels to distribute sound, for example, by streaming the audio objects over a network to a client device. The objects can define their locations in space with associated two or three dimensional coordinates. The objects can be adaptively streamed to the client device based on available network or client device resources. A renderer on the client device can use the attributes of the objects to determine how to render the objects. The renderer can further adapt the playback of the objects based on information about a rendering environment of the client device. Various examples of audio object creation techniques are also described.

Abstract: A system and method of remotely enabling sound enhancement techniques is disclosed. In an embodiment, a watermark is embedded in an encoded multi-channel audio stream to remotely enable an enhancement decoder portion of a multi-channel audio decoder.

Abstract: In an embodiment, a phase compensation system shifts the phase of an audio signal in a mid-range frequency band to compensate for phase distortion created when an electrical audio signal is converted to audio by an electronic transducer, such as a loudspeaker. An audio enhancement system mixes at least the phase compensated signal, an enhanced audio signal, and the left and right audio input signals to generated phase compensated left and right audio output signals.

Abstract: In certain embodiments, an improved audio equalization filter can be generated by frequency warping one or more digital filters having a plurality of frequency bands. Frequency warping can include, for example, transforming at least some of the frequency bands of the one or more digital filters into lower frequency bands. As a result, in various implementations the audio equalization filter may be more accurate than certain currently-available IIR equalization filters. The audio equalization filter may also be more computing-resource efficient than certain currently-available FIR equalization filters.

Abstract: Systems and methods of processing audio signals are described. The audio signals comprise information about spatial position of a sound source relative to a listener. At least one audio filter generates two filtered signals for each of audio signal. The two filtered signals are mixed with other filtered signals from other audio signals to create a right output audio channel and a left audio output channel, such that the spatial position of the sound source is perceptible from the right and left audio output channels.

Abstract: A stereo enhancement system processes the difference signal component generated from a pair of left and right input signals to create a broadened stereo image reproduced through a pair of speakers or through a surround sound system. Processing of the difference signal component occurs through equalization characterized by amplification of the low and high range of auditory frequencies. The processed difference signal is combined with a sum signal, generated from the left and right input signals, and the original left and right input signals to create enhanced left and right output signals.

Abstract: Systems and processes for transmission of multi-channel audio from a sender to one or more recipients. Multi-channel audio is encoded with a plurality of different dialog channels. The encoded multi-channel audio and dialog channels can be compressed to facilitate transmission with limited bandwidth. A recipient can select a desired dialog channel from the plurality of dialog channels transmitted. A receiver side decoder can reconstruct a multi-channel audio with the selected dialog for playback. The plurality of dialog options can include different languages, different dialects, different accents, and/or different viewpoints/biases.

Abstract: An acoustic correction apparatus processes a pair of left and right input signals to compensate for spatial distortion as a function of frequency when the input signals are reproduced through speakers in a sound system. The sound-energy of the left and right input signals is separated and corrected in a first low-frequency range and a second high-frequency range. The resultant signals are recombined to create image-corrected audio signals having a desired sound-pressure response when reproduced by the speakers in the sound system. The desired sound-pressure response creates an apparent sound image location with respect to a listener. The image-corrected signals may then be spatially enhanced to broaden the apparent sound image.