Abstract: To realize virtual surround reproduction with small deterioration in the SN ratio of an entire reproduction system, in the case of adding together virtual surround signals and front-channel audio signals in an adder 1300, volume normalization is carried out in a volume normalizing section 1200 before the addition. In the case where the addition is not performed, the virtual surround signals and the front-channel audio signals are output independently of each other without being subjected to volume normalization in the volume normalizing section 1200.

Abstract: A spatial element is added to communications, including over telephone conference calls heard through headphones or a stereo speaker setup. Functions are created to modify signals from different callers to create the illusion that the callers are speaking from different parts of the room.

Abstract: The present invention is directed toward conference calls and methods, devices, and systems for facilitating a conference call. Specifically, the present invention allows participants of a conference call to selectively alter or mute other participants' voices in a conference call. More specifically, a number of participants may be associated with a single communication device and only a subset of those participants may have their voice signal altered or muted during the conference call.

Abstract: The estimation of an HRTF for a given individual is accomplished by means of a coupled model, which identifies the dependencies between one or more images of readily observable characteristics of an individual, and the HRTF that is applicable to that individual. Since the HRTF is highly influenced by the shape of the listener's outer ear, as well as the shape of the listener's head, images of a listener which provides this type of information are preferably applied as an input to the coupled model. In addition, dimensional measurements of the listener can be applied to the model. In return, the model provides an estimate of the HRTF for the observed characteristics of the listener.

Abstract: Audio loudspeaker and headphone virtualizers and cross-talk cancellers and methods use separate virtual speaker locations for different Bark frequency bands and a single reverberation filter for multi-channel virtualizer inputs.

Abstract: A sound localization apparatus capable of localizing a sound image at a given position, in a simple configuration is provided with: a first signal processor for convoluting an input audio signal with a first impulse response corresponding to a path from a reference sound source position to the listener's left ear to generate a left-channel audio signal for localization; a second signal processor for convoluting the input audio signal with a second impulse response corresponding to a path from the reference sound source position to the listener's right ear to generate a right-channel audio signal for localization; and a third signal processor for applying a third impulse response so as to localize a sound image obtained by reproducing the audio signals for localization at a position different from the reference sound source position.

Abstract: A compact audio reproduction system for two input signals includes at least four loudspeakers disposed at the vertices of a quadrilateral not more than two feet on any side and such that no two loudspeakers are located at a distance from one another which is less than one-fourth the greatest distance between any two loudspeakers. The two input signals are connected to alternate speakers such that no two loudspeakers at adjacent vertices of the quadrilateral produce the same signal such that a listener at an arbitrary location perceives a sound source larger than the quadrilateral and significant stereo image. The signals received by two loudspeakers located at adjacent vertices may receive signals which are equalized separately from the signals received by the other loudspeakers for the purpose of reducing comb filtering and improving the tolerance of the device to placement near walls and other obstructions.

Abstract: Loudspeakers in domestic or automotive environments are rarely placed ideally with respect to the sources supplying them, and the stereo and surround images are seldom satisfying. According to the invention there is provided a method and apparatus for combining a precise knowledge about the relative positions of the loudspeakers that were intended (the virtual loudspeakers) and a precise knowledge about the actual placement of listening loudspeakers into a vector space that enables calculation of running corrections to the signals used in order to simulate the presence of the virtual loudspeakers. Specifically the corrections may comprise gain/attenuations determined based on the distances in vector space between the virtual and actual loudspeakers and delays determined from these distances.

Abstract: A method of providing an audio signal to a headphone apparatus for a user is disclosed. The method comprises providing a headphone apparatus comprising at least one left speaker for a left ear of a user having a sound path from the left speaker to the left ear canal and at least one right speaker for a right ear of the user having a sound path from the right speaker to the right ear canal, wherein the sound path of the left speaker has a different length from the sound path of the right speaker. The method further comprises sending an audio signal simultaneously to the left speaker and right speaker thereby creating a timing difference in the time the signal is received by each ear canal based on the difference is the length of the sound path.

Abstract: An audio signal is supplied to a loudspeaker array to perform wavefront synthesis. A virtual sound source is produced at an infinite distance using wavefront synthesis.

Abstract: The invention relates to a method of processing an input signal into a phantomized signal, including adding at least one attenuated delayed signal to the input signal, the phantomized signal having at least one delayed attenuated signal and the input signal. A phantomized signal according to the invention offers a new and impressive integration of a center channel signal of a multi channel audio system into the complete audio image provided by the system.

Abstract: The invention relates to a method and a device for reproducing a binaural output signal generated from a monaural input signal and comprising a first output signal and a second output signal via at least a first and a second speaker of a binaural headset particularly for VoIP applications.

Abstract: A method of audio scene management in a teleconference or other group sound telecommunication is presented, in which teleconference at least a first transmitting party, a second transmitting party and a receiving party participates. The method comprises receiving of signals representing sound of the first transmitting party and sound of the second transmitting party. The method further comprises obtaining of measures of sound activity for the first and second transmitting parties, respectively and selecting a first angle and/or a second angle based on the obtained measures of sound activity. The method further comprises processing of the received signals into processed signals such that sound from the first transmitting party is experienced by the receiving party as emanating from the first angle while sound from the second transmitting party is experienced as emanating from the second angle, with respect to the receiving party. Finally signals representing the processed signals are outputted.

Abstract: A method for headphone reproduction of at least two input channel signals is proposed. Said method comprises for each pair of input channel signals from said at least two input channel signals the following steps. First, a common component, an estimated desired position corresponding to said common component, and two residual components corresponding to two input channel signals in said pair of input channel signals are determined. Said determining is being based on said pair of said input channel signals. Each of said residual components is derived from its corresponding input channel signal by subtracting a contribution of the common component. Said contribution is being related to the estimated desired position of the common component. Second, a main virtual source comprising said common component at the estimated desired position and two further virtual sources each comprising a respective one of said residual components at respective predetermined positions are synthesized.

Abstract: A sound processing system for a vehicle includes a sound processor that is configured to mix at least one real audio input signal to form at least one virtual output signal. At least one audio signal that is available to drive at least one loudspeaker may be formed using the combination of the virtual output signal and the real audio input signal. The virtual output signal may be post processed to form a predetermined frequency range of the audio signal prior to being combined with the real audio input signal. The audio signal may be created by mixing the real audio input signal with the post processed virtual output signal. Alternatively, the audio signal may be formed by mixing the real audio input signal to form a real audio output signal, and then summing the real audio output signal with the post processed virtual output signal. Mixing may be performed with a crossbar mixer included in the sound processor.

Abstract: A system for providing a listener with an augmented audio reality in a geographical environment said system comprising a position locating system for determining a current position and orientation of a listener in.

Abstract: A surround sound virtualization apparatus and method. The surround sound virtualization apparatus may include an audio decoder to perform head-related transfer function (HRTF) filtering, and a time delay unit to provide a time delay to a plurality of output signals of the audio decoder.

Abstract: A sound image localization apparatus for localizing a reproduced sound image at a sound source position convolves an impulse response through each path from an optimal position of localization of a sound source to the left and right ears of the listener into an audio signal to generate an audio signal for localization on the left and right channels. The impulse response is convolved after down sampling the audio signal localized to the position of the sound source behind the listener and thereby the amount of operation required of a signal processor for convoluting the impulse response is greatly reduced without spoiling a spatial localization of the sound image.

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: An audio reproduction system is divided into a central wave-field synthesis module and a plurality of loudspeaker modules disposed in a distributed way, wherein synthesis signals for the individual loudspeakers as well as corresponding channel information associated to the synthesis signals are calculated in the central wave-field synthesis module. The synthesis signals for a loudspeaker as well as associated channel information will then be transmitted to respective loudspeaker modules via a transmission path, wherein every loudspeaker module obtains the synthesis signals and associated channel information intended for the loudspeaker associated to the loudspeaker module. A distributed audio rendering and digital/analog converting takes place in the loudspeaker module to generate the actually analog loudspeaker signals in a distributed way in spatial proximity to every loudspeaker.

Abstract: A stereophonic device for headphones to which a monophonic signal or a stereophonic signal is inputted comprises an uncorrelating processing unit for reducing the correlation between two signals obtained by dividing the inputted monophonic signal into two channels or two signals constituting the inputted stereophonic signal, a reflected sound adding processing unit for adding a reflected sound, and a sound image localizing processing unit for controlling the position where a sound image is localized.

Abstract: To provide a surround sound reproducing system capable of obtaining high realistic sensation even in the case where an integral surround speaker cannot be installed rearward of a listening position. A surround system 100 is constructed by: a sound source output device 110 for outputting bit stream data of a predetermined format; a signal processor 120 for performing a signal process on every audio signal of each channel; and a speaker system 130 made of various speakers corresponding to various channels and including an integral surround speaker. The signal processor 120 has a signal processing unit 200 including: a switch control unit 203 for selecting one of right and left surround signals amplified from a surround speaker; a frequency correcting circuit 204 for correcting the frequency characteristic of the surround signal selected by the switch control unit 203; and an adder 205 for adding the surround signal whose frequency characteristic was corrected to a main signal.

Abstract: Techniques are disclosed for sound source localization based on joint learning and evaluation of ITD and ILD representations that are measured in a complementary, correlation-based way using binaural time-frequency spectrums. According to one embodiment, from these measurements and learned representatives, which may, for example, be created by combinations of measurements from signals belonging to the same class, i.e., the same azimuthal location, probability distributions over frequency and class are computed. These probability distributions can be combined over cue and frequency using information-theoretic approaches to get a robust classification of the location and additionally a confidence measure for the quality of the classification result.

Abstract: The invention describes a method for processing sound signals for a surround left channel (SL) and a surround right channel (SR). Thereby, a continually varying delay between the resulting signals of the surround right (SR) and surround left channels (SL) is generated. Furthermore the invention describes a delay management unit, a sound processing system, an acoustic system comprising such a sound processing system, a mixing unit for such an acoustic system and a studio system comprising such a sound processing system.

Abstract: In a wave field synthesis apparatus for driving an array of loudspeakers with drive signals, the loudspeakers being arranged at different defined positions, a drive signal for a loudspeaker being based on an audio signal associated with a virtual source having a virtual position with reference to the loudspeaker array and on the defined position of the loudspeaker, at first relevant loudspeakers of the loudspeaker array are determined on the basis of the position of the virtual source, a predefined listener position, and the defined positions of the loudspeakers, so that artifacts due to loudspeaker signals moving opposite to a direction from the virtual source to the predefined listener position are reduced.

Abstract: A sound reproducing apparatus for providing an optimal virtual sound source and a sound reproducing method therefor are provided. The sound reproducing apparatus includes a virtual sound signal generation unit for generating more than one virtual sound signal corresponding to locations and the number of target virtual sound sources on the basis of more than one inputted sound signal, and a virtual sound signal downmix unit for downmixing said more than one virtual sound signal to virtual sound signal outputs corresponding to a predetermined number of output channels. The number and locations of diversely variable virtual sound sources are provided, thereby obtaining an effect of providing an optimal virtual sound source adaptively depending on each different environment.

Abstract: A sound processing apparatus includes: sound image localization processing means for performing a sound image localization process on a sound signal to be reproduced; a speaker section placeable over an ear of a user and supplied with the sound signal to emit sound in accordance with the sound signal; turning detection means provided in the speaker section to detect turning of the head of the user; inclination detection means provided in the speaker section to detect inclination of the turning detection means; turning correction means for correcting detection results from the turning detection means on the basis of detection results of the inclination detection means; and adjustment means for controlling the sound image localization processing means so as to adjust the localized position of a sound image on the basis of the detection results from the turning detection means corrected by the turning correction means.

Abstract: A digital wireless earphone device with stereo or multiple-channel sound effect automatic detection and switching functions is provided. The multiple-channel digital wireless earphone device uses a signal processing and transmitting device to decode multiple-channel signal sources. After the decoding is completed, the multiple-channel signal sources are concurrently transmitted to a wireless earphone end through a radio. After being directly digital-to-analog converted and amplified, the multiple-channel signals are connected to a plurality of speakers to generate a multiple-channel surround sound field. The wireless earphone at a receiving end further has an automatic detection function for detecting a 6CH or 2CH sound source and automatically selects an earphone playing mode accordingly.

Abstract: A sound image control device filters transfer functions H3 and H1 indicating transfer characteristics of a sound from an acoustic transducer (8) to entrances to respective ear canals (1) and (2) as well as filtering transfer functions H4 and H2 from an acoustic transducer (9) to the entrances to the respective ear canals (1) and (2) and generates second transfer functions H6 and H5 indicating transfer characteristics of a sound to the entrances to the respective ear canals (1) and (2) from a target sound source (11) at a location different from the sound sources, the sound image control device being equipped with correction filters (13) and (14) that (i) store characteristic functions E1 and E2 for performing filtering operations on the first transfer functions H1, H2, H3, and H4 and (ii) generate the second transfer functions H5 and H6 from the first transfer functions H1, H2, H3, and H4 using such characteristic functions E1 and E2.

Abstract: The method and apparatus described herein generates realistic audio for a virtual reality simulation based on the position (location and orientation) of a participant's head. The audio may be generated based on independent and dependent audio profiles. The independent audio profile represents the participant-independent propagation of sound from a virtual source to each of one or more virtual objects in the simulation. The dependent audio profile represents the propagation of the sound from each of the one or more virtual objects to the head or ears of the participant based on a position of the participant's head or ears. An audio processor generates the desired audio signal at the head of the participant by combining the dependent and independent audio profiles to determine a total audio profile for the virtual source, and filtering an audio wave corresponding to the virtual source based on the total audio profile.

Abstract: The input signal X of one channel is divided by a multi-stage delay processing device Z?1 and each of the outputs is superimposed by a specified coefficient by a coefficient processing device W0, W1, . . . , Wk. The results are added by an adder, thereby providing a correlation eliminating filter for extracting a signal component from the input signal X of one channel having a high correlation with the input signal Y of the other channel. There is provided a coefficient updating processing device 5 for successively changing the feature of the correlation eliminating filter according to an error signal e obtained from the output signal RES and the input signal Y from the other channel, and the input signal X of one channel. A surround signal is obtained from a difference between the output RES from the correlation eliminating filter and the input signal Y of the other channel.

Abstract: A method to process audio signals, an apparatus accepting audio signals, a carrier medium that carried instructions for a processor to implement the method to process audio signals, and a carrier medium carrying filter data to implement a filter of audio signals. The method includes filtering a pair of audio input signals by a process that produces a pair of output signals corresponding to the results of: filtering each of the input signals with a HRTF filter pair, and adding the HRTF filtered signals. The HRTF filter pair is such that a listener listening to the pair of output signals through headphones experiences sounds from a pair of desired virtual speaker locations.

Abstract: A method to process audio signals, an apparatus accepting audio signals, a carrier medium that carried instructions for a processor to implement the method to process audio signals, and a carrier medium carrying filter data to implement a filter of audio signals. The method includes filtering a pair of audio input signals by a process that produces a pair of output signals corresponding to the results of: filtering each of the input signals with a HRTF filter pair, and adding the HRTF filtered signals. The HRTF filter pair is such that a listener listening to the pair of output signals through headphones experiences sounds from a pair of desired virtual speaker locations.

Abstract: A personal listening device used in connection with the amplification of signals for enhancing the perceived quality and ambiance of sound heard by listener using stereo headphones or small speaker systems utilizes a difference signal that is cross-fed between stereo channels. The invention provides a perception of spatial presence in music sound when used with either stereo headphones or small speaker systems. The circuitry, wiring and packaging provide for multiple output jacks allowing for convenient sharing of the enhanced output signal from a personal listening device with other persons using headphones. The invention provides effects similar to stereo enhancement, surround sound, and psychoacoustic imagery in a small, inexpensive package for enhancing a user's audio experience.

Abstract: A frequency-domain method for format conversion or reproduction of 2-channel or multi-channel audio signals such as recordings is described. The reproduction is based on spatial analysis of directional cues in the input audio signal and conversion of these cues into audio output signal cues for two or more channels in the frequency domain.

Abstract: An audio processing apparatus has converting means for converting n-channel (positive integral number: n?1) audio signals input from at least one sound source into two-channel signals, a pair of correcting filter means to which a pair of two-channel signals converted by the converting means are supplied and which corrects a difference of the sense of hearing due to a difference of headphone characteristics, and an output section for supplying a pair of output signals from the pair of correcting filter means to right and left speaker units of a headphone.

Abstract: The user (2) of a binaural hearing aid or communication system (1A, 1B) is to be provided with an easier assignment or identification of acoustic signals generated in the system for keeping a user (2) informed about current settings or states of the system. To this end the signal is emitted by the hearing aid or communication system (1A, 1B) in such a way that for the user (2) the signals appear to come from different signal sources (3 to 6; 8 to 11) in the space (7) surrounding the user. In this way the acoustic signals carry additional information perceived consciously or unconsciously by the user (2).

Abstract: A digital audio signal processing system and method transforms two-channel stereo time-domain data into the frequency domain. Vector operations are performed upon the frequency-domain data by which signal components unique to one of the input channels are routed to one of the output channels, signal components unique to the other of the input channels are routed to another of the output channels, and signal components common to both channels are routed to a third and optionally to a fourth output channel. The frequency-domain output channels are then transformed back into the time-domain, forming an equivalent number of channels of output audio data. The vector operations are performed in a manner that preserves the overall information content of the input data.

Abstract: An apparatus for creating, utilizing a pair of oppositely opposed headphone speakers, the sensation of a sound source being spatially distant from the area between the pair of headphones, the apparatus comprising: (a) a series of audio inputs representing audio signals being projected from an idealised sound source located at a spatial location relative to the idealised listener; (b) a first mixing matrix means interconnected to the audio inputs and a series of feedback inputs for outputting a predetermined combination of the audio inputs as intermediate output signals; (c) a filter system of filtering the intermediate output signals and outputting filtered intermediate output signals and the series of feedback inputs, the filter system including separate filters for filtering the direct response and short time response and an approximation to the reverberant response, in addition to the feedback response filtering for producing the feedback inputs; and (d) a second matrix mixing means combining the filtered

Abstract: An apparatus for creating, utilizing a pair of oppositely opposed headphone speakers, the sensation of a sound source being spatially distant from the area between the pair of headphones, the apparatus comprising: (a) a series of audio inputs representing audio signals being projected from an idealised sound source located at a spatial location relative to the idealised listener; (b) a first mixing matrix means interconnected to the audio inputs and a series of feedback inputs for outputting a predetermined combination of the audio inputs as intermediate output signals; (c) a filter system of filtering the intermediate output signals and outputting filtered intermediate output signals and the series of feedback inputs, the filter system including separate filters for filtering the direct response and short time response and an approximation to the reverberant response, in addition to the feedback response filtering for producing the feedback inputs; and (d) a second matrix mixing means combining the filtered

Abstract: In a short range radio communication headset, signals transmitted by the short range radio communications are received while direct sounds propagated from an external are detected. Then, a digital signal adaptation processing using either received signals or the direct sounds as reference signals are applied, and a ratio between the received signals and the direct sounds is controlled by correlating the reference signals and another one of the received signals and the direct sounds that are not used as the reference signals and extracting necessary components.

Abstract: A distributing circuit distributes audio signals of a predetermined number of channels to audio signals of a predetermined number of channels. A first signal processing circuit processes audio signals that are output from the distributing circuit in parallel, reproduces the resultant signals with a plurality of speakers, and localizes sound images of the individual audio signals at predetermined positions. A second signal processing circuit inputs audio signals that are output to the plurality of speakers and performs signal processes equivalent to the transfer functions from the individual speakers to both the ears of the listener. The output signals of the second signal processing circuit are reproduced with the headsets.

Abstract: A binaural technology method includes: determining positions related to position of both ears of a listener, receiving a wireless RF signal including binaural audio data is received, and presenting the binaural audio data to the listener By determining ear positions of a listener e.g. in 3D, information of the listener's position e.g. in a virtual environment is known, and further by wireless transmitting binaural audio signals to the listener, it becomes possible to transmit 3D audio data matching the listener's position and movements accordingly. Further, since the position of both ears is known, it is possible to individually match the binaural audio data to the listener, since it is possible to derive from the ear positions a distance between the listener's ears, and hereby a valuable parameter is known that can be used to generate binaural signals that individually fits the listener. Thus, the listener can be provided with a better 3D audio experience.

Abstract: In a situation where a plurality of virtual sound sources are fixedly located, a mixing system allows a listener to increase or decrease the sound volumes of the virtual sound sources with a simple operation. Directional angle difference detection means 24 detects a directional angle difference between a predetermined reference directional angle and an indicated directional angle which is determined by the listener by pointing with an operation unit 7 a certain direction in a virtual space where the virtual sound sources exist. Mixing means 5 mixes a plurality of audio signals supplied from a plurality of audio channels and outputs a mixed audio signal without adjustment, when the directional angle difference is zero degrees.

Abstract: An apparatus and a method for providing music file search function. The apparatus includes an input unit that receives an input of an attribute of a music file to be played, an extract unit that extracts a characteristic segment from the music file according to the input attribute, a 3D-sound generating unit that generates 3D sound from the characteristic segment of the music file along a spatial axis corresponding to the attribute, and an output unit that outputs the 3D sound. The method includes the steps of inputting an attribute of a music file to be played, searching a characteristic segment of the music file according to the input attribute, generating 3D sound from the characteristic segment of the music file along a spatial-axis corresponding to the attribute, and outputting the 3D sound.

Abstract: The present invention provides an audio information transforming method, a program product, a device, an encoder, and an video/audio format utilized therein, which are capable of providing an audio information by adjusting the Doppler effect caused by movement of the object, in response to change of the listening point. In the invention, a virtual listening point is set at a position different from a basic listening point where a listener listens to a sound of an object, then a velocity of the object observed from the virtual listening point is calculated based on position information of the virtual listening point and position information of the object. Then, an audio frequency of an audio heard at the virtual listening point is changed based on the calculated velocity. For example, the frequency of the sound is increased if the object approaches the virtual listening point, and the frequency is decreased if opposite.

Abstract: A headphone for sound-source compensation and sound-image positioning and recovery is provided, including a left speaker device for playing to a left ear of a user left channel sound and right channel sound originating from at least a sound signal, and a right speaker device for playing to a right ear of the user left channel sound and right channel sound originating from the sound signal. A user wearing the headphone of the invention perceives stereo sound field and sound image positioning seemingly provided by a loudspeaker.

Abstract: A data processing apparatus is designed for simulating an acoustic characteristic of an acoustic space which contains a sound source for generating a sound and a sound receiving point for receiving the sound. In the apparatus, each of a plurality of characteristic control sections processes sound data and outputs the processed sound data. The characteristic control sections correspond to transmission paths which must exist in the acoustic space such that the sound generated from the sound source travels to the sound receiving point through the respective transmission paths. An instruction section provides a processing instruction of the sound data to each characteristic control section such that each characteristic control section processes the sound data according to the provided processing instruction to thereby execute the simulation of the sound traveling through the corresponding transmission path.

Abstract: Input digital sound signals are subjected to filtering for convolution of respective impulse responses, and the resulting signals are supplied to time delay setting circuits. In each of the time delay setting circuits, output signals from two adjacent stages of the time delay setting circuits, which correspond to a direction closest to a detected facing direction of a listener, are taken out as two pairs of signals. In crossfade processing circuits, the signals in each pair are added at a proportion depending on the detected facing direction of the listener. Output signals of the crossfade processing circuits are taken out through correction filters for compensating frequency characteristic changes in a high frequency range. As a result, when listening to sound with headphones and localizing a sound image at an arbitrary fixed position outside the listener's head, noises generated upon a change in the facing direction of the listener are reduced.

Abstract: A sound processing system for a vehicle includes a sound processor that is configured to mix at least one real audio input signal to form at least one virtual output signal. At least one audio signal that is available to drive at least one loudspeaker may be formed using the combination of the virtual output signal and the real audio input signal. The virtual output signal may be post processed to form a predetermined frequency range of the audio signal prior to being combined with the real audio input signal. The audio signal may be created by mixing the real audio input signal with the post processed virtual output signal. Alternatively, the audio signal may be formed by mixing the real audio input signal to form a real audio output signal, and then summing the real audio output signal with the post processed virtual output signal. Mixing may be performed with a crossbar mixer included in the sound processor.