| Patent application number | Description | Published |
|---|
| 20080212797 | BASS BOOST FILTERING TECHNIQUES - Bass frequencies of audio can be boosted using various techniques and tools. The described techniques and tools can be applied separately or in combination. For example, bass frequencies of audio can be boosted using an integer bass boost filter by receiving user-settable parameters, such as “c” and “s” coefficients, and implementing the integer bass boost filter using a coupled form structure implementation and the user-settable parameters. Bass frequencies of audio can also be boosted using an integer bass boost filter that is configured to use any of plural coupled form structure implementations. Bass frequencies of audio can be also be boosted using a linear combination of an input audio signal and output of a high-pass filter. | 09-04-2008 |
| 20080267427 | LOUDNESS-BASED COMPENSATION FOR BACKGROUND NOISE - Loudness-based compensation systems and techniques are described which provide audio compensation in noisy environments. Loudness approximations are determined for an audio block both by itself and in the presence of background noise. These approximations utilize compression of audio intensity within frequency bands in order to better reflect listeners' hearing perception. From these loudness approximations, a gain is determined for the audio block and then applied in such a manner that the effect is not jarring to listeners. | 10-30-2008 |
| 20090060236 | LOUDSPEAKER ARRAY PROVIDING DIRECT AND INDIRECT RADIATION FROM SAME SET OF DRIVERS - An array loudspeaker includes a plurality of drivers arranged in an array configuration. A digital signal processor-based control system processes direct audio signal and indirect audio signal inputs for the loudspeaker to simultaneously produce direct sound in the form of a directed beam or wavefront, and indirect sound as a perceptually diffuse soundfield. | 03-05-2009 |
| 20090080632 | SPATIAL AUDIO CONFERENCING - Audio in an audio conference is spatialized using either virtual sound-source positioning or sound-field capture. A spatial audio conference is provided between a local and remote parties using audio conferencing devices (ACDs) interconnected by a network. Each ACD captures spatial audio information from the local party, generates either one, or three or more, audio data streams which include the captured information, and transmits the generated stream(s) to each remote party. Each ACD also receives the generated audio data stream(s) transmitted from each of the remote parties, processes the received streams to generate a plurality of audio signals, and renders the signals to produce a sound-field that is perceived by the local party, where the sound-field includes the spatial audio information captured from the remote parties. A sound-field capture device is also provided which includes at least three directional microphones symmetrically configured about a center axis in a semicircular array. | 03-26-2009 |
| 20090080675 | DYNAMIC BASS BOOST FILTER - Bass frequencies of audio can be dynamically boosted using various techniques and tools. The described techniques and tools can be applied separately or in combination. Bass frequencies of audio can be boosted using a linear combination of an input audio signal and output of a high-pass filter. For example, bass frequencies of audio can be boosted by applying a high-pass filter to an input audio signal to produce an output of the high-pass filter, determining a current level, determining a target gain amount, dynamically adjusting the input audio signal and the output of the high-pass filter, and combining the gain-adjusted signals to produce an output signal. A dynamic bass boost filter can comprise a high-pass filter and a dynamic boost module. | 03-26-2009 |
| 20090116664 | PERCEPTUALLY WEIGHTED DIGITAL AUDIO LEVEL COMPRESSION - The level of an audio signal can be compressed by receiving an input audio signal, determining a measure of loudness of the signal using a perceptually derived filter, determining a target gain amount, determining a current gain amount using piecewise linear attack/release logic, and producing an output audio signal by adjusting the input audio signal by the current gain amount. An audio compression filter for compressing the level of audio can comprise a loudness measuring module configured to determine a measure of loudness using a perceptually derived filter, and a compression module configured to determine a target gain amount, determine a current gain amount using piecewise linear attack/release logic, and adjust an input audio signal by the current gain amount. Audio level compression can be implemented using integer calculations. | 05-07-2009 |
| 20090136066 | STEREO IMAGE WIDENING - A stereo image can be widened by converting a stereo audio signal into a sum-difference audio signal, applying HRTF processing to the difference channel, and producing an output stereo audio signal. A stereo image can also be widened by receiving a stereo signal, converting the stereo signal into a sum-difference signal, applying HRTF processing to only the difference channel, upsampling the sum-difference signal, applying distortion, downsampling the sum-difference signal, and converting the sum-difference signal into a stereo signal. A system for widening a stereo image can comprise an input module configured to convert a stereo audio signal into a sum-difference audio signal, an HRTF module configured to apply HRTF processing to only the difference channel, a distortion module configured to apply a first distortion to the sum channel and a second different distortion to the difference channel, and an output module configured to produce an output stereo audio signal. | 05-28-2009 |
| 20090185693 | MULTICHANNEL SOUND RENDERING VIA VIRTUALIZATION IN A STEREO LOUDSPEAKER SYSTEM - A speaker virtualization system provides virtual surround sound using a pair of physical loudspeakers. A multiple surround audio channels input is processed using a combination of head related transfer functions and shaped reverberation to provide widening and front/back auditory clues without requiring any kind of interaural path cancellation. The system uses a 360 degree power-response head related transfer function to provide perceptual separation of the reverberant and direct paths, along with discrete, different reverberation for left and right rendering channels to provide envelopment. By eliminating interaural path cancellation, the speaker virtualization system also produces a wider virtual surround sound effect, without dependency on head position and facing. | 07-23-2009 |
| 20090310802 | VIRTUAL SOUND SOURCE POSITIONING - Systems and methods for determining a virtual sound source position by determining an output for loudspeakers by the position of the loudspeakers in relation to a listener. The output of respective loudspeakers is generated using aural cues to give the listener knowledge of the virtual position of the virtual sound source. Both a gain in intensity and a delay are simulated. | 12-17-2009 |
| 20100040243 | Sound Field Widening and Phase Decorrelation System and Method - A system for decorrelating signals including a first all pass filter, having a first delay length, processing a first signal. A second all pass filter, having a second delay length, is connected to the first all pass filter and processes the first signal after processing by the first all pass filter. A third all pass filter, having a third delay length, processes a second signal. A fourth all pass filter, having a fourth delay length, is connected to the third all pass filter and processes the second signal after processing by the third all pass filter. The first delay length, the second delay length, the third delay length and the fourth delay length each have a unique value, and the sum of the first delay length and the second delay length is equal to the sum of the third delay length and the fourth delay length. | 02-18-2010 |
| 20100054482 | Interaural Time Delay Restoration System and Method - An apparatus for processing audio data comprising an interaural time delay correction factor unit for receiving a plurality of channels of audio data and generating an interaural time delay correction factor. An interaural time delay correction factor insertion unit for modifying the plurality of channels of audio data as a function of the interaural time delay correction factor. | 03-04-2010 |
