72 results about "Wave field synthesis" patented technology

Arrangement of a sound reproduction system (1), including at least one input (2), a sound field generator (4), a loudspeaker panel (10); the at least one input (2) connected to the sound field generator (4), and the sound field generator (4) connected to the loudspeaker panel (10); the at least one input (2) arranged for generating an audio signal; the sound field generator (4) including a wave field synthesizer (6) arranged for generating a spatially perceptible sound field for the audio signal and for outputting the spatially perceptible sound field to the loudspeaker panel (10), the loudspeaker panel (10) being a multi-exciter Distributed Mode Loudspeaker panel (10) consisting of a plate (12) and a plurality of transducers (16), arranged within an array (14) on the large plate (12) for reproducing the spatially perceptible sound field from the wave field synthesizer (6) by exciting bending waves in the plate (12).

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. Downstream to means for calculating the drive signal components for the relevant loudspeakers and for a virtual source, there is means for providing the drive signal components for the relevant loudspeakers for the virtual source to the relevant loudspeakers, wherein no drive signals for the virtual source are provided to loudspeakers of the loudspeaker array not belonging to the relevant loudspeakers. With this, artifacts in an area of the audience room due to a generation wave field are suppressed, so that in this area only the useful wave field is heard in artifact-free manner.

A perceptually motivated spatial decomposition for two-channel stereo audio signals, capturing the information about the virtual sound stage, is proposed. The spatial decomposition allows to re-synthesize audio signals for playback over other sound systems than two-channel stereo. With the use of more front loudspeakers, the width of the virtual sound stage can be increased beyond + / - 30 DEG and the sweet spot region is extended. Optionally, lateral independent sound components can be played back separately over loudspeakers on the two sides of a listener to increase listener envelopment. It is also explained how the spatial decomposition can be used with surround sound and wavefield synthesis based audio system. According to the main embodiment of the invention applying to multiple audio signals, it is proposed to generate multiple output audio signals (y1,..., yM) from multiple input audio signals (x1, ..., xL), in which the number of output is equal or higher than the number of input signals , this method comprising the steps of: by means of linear combinations of the input subbands (X1(i), ..., XL(i)), computing one or more independent sound subbands representing signal components which are independent between the input subbands, by means of linear combinations of the input subbands (X1(i), ..., XL(i)), computing one or more localized direct sound subbands representing signal components which are contained in more than one of the input subbands and direction factors representing the ratios with which these signal components are contained in two or more input subbands, generating the output subband signals (Y1(i)...YM(i)), where each output subband signal is a linear combination of the independent sound subbands and the localized direct sound subbands, converting the output subband signals (Y1(i)...YM(i)), to time domain audio signals (y1,..., yM).

A sound system obtains a desired sound field from an array of sound sources arranged on a panel. The desired sound field allows a listener to perceive the sound as if the sound were coming from a live source and from a specified location. Setup of the sound system includes arranging a microphone array adjacent the array of sound sources to obtain a generated sound field. Arbitrary finite impulse response filters are then composed for each sound source within the array of sound sources. Iteration is applied to optimize filter coefficients such that the generated sound field resembles the desired sound field so that multi-channel equalization and wave field synthesis occur. After the filters are setup, the microphones may be removed.

Disclosed are an apparatus and method of surround wave field synthesizing a multi-channel signal excluding sound image localization information. A wave field synthesis and reproduction apparatus may include a signal classification unit to classify an inputted multi-channel signal into a primary signal and an ambient signal, a sound image localization information estimation unit to estimate sound image localization information of the primary signal and sound image localization information of the ambient signal, and a rendering unit to render the primary signal and the ambient signal based on the sound image localization information of the primary signal, the sound image localization information of the ambient signal, and listener environment information.

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. The division into a central wave-field synthesis module and the plurality of distributed loudspeaker modules allows that audio reproduction systems that are scalable with regard to the price can be generated in order to offer systems of different size scalable in price particularly for cinema reproduction rooms varying strongly in size.

For simulating a wave field synthesis system, an audio scene description defining a temporal sequence of audio objects is provided, an audio object having an audio file for a virtual source or a reference to the audio file and information on a source position of the virtual source. Furthermore, an output condition the wave field synthesis system is to satisfy is given. Furthermore, a simulator for simulating the behavior of the wave field synthesis system for the audio scene description, using the audio data and the source positions as well as information on the wave field synthesis system, is provided. Finally a checker performs a check to determine if the simulated behavior of the wave field synthesis system satisfies the output condition. This achieves more flexible audio scene description creation as well as flexible portability of an audio scene description developed for one system to another wave field synthesis system.

For a level correction in a wave field synthesis system having a wave field synthesis module and an array of loudspeakers for providing sound to a presentation region, a correction value which is based on a set amplitude state in a presentation region is determined, the set amplitude state depending on a position of the virtual source or a type of the virtual source, and the actual amplitude state in the presentation region depending on the component signals for the loudspeakers due to the virtual source. The correction value determined is fed to a manipulator manipulating the audio signal associated to the virtual source before feeding to the wave field synthesis module, or the component signals for the individual loudspeakers due to the virtual source are manipulated to reduce a deviation between a set amplitude state and an actual amplitude state at one point or several in the presentation region.

An encoder / decoder for multi-channel audio data, and in particular for audio reproduction through wave field synthesis. The encoder comprises a two-dimensional filter-bank to the multi-channel signal, in which the channel index is treated as an independent variable as well as time, and and the resulting spectral coefficient are quantized according to a two-dimensional psychoacoustic model, including masking effect in the spatial frequency as well as in the temporal frequency. The coded spectral data are organized in a bitstream together with side information containing scale factors and Huffman codebook identifiers.

Provided are an apparatus and a method for reproducing a surround wave field using wave field synthesis. The apparatus includes an audio signal analyzer for analyzing a received multi-channel audio signal to check the number of audio signal channels, and extracting a sound source signal for each checked channel from the multi-channel audio signal; a wave field synthesis renderer for localizing the extracted sound source signal for each channel at a virtual sound image outside a narrow space using wave field synthesis so that the extracted sound source signal is suitable for the number of the checked audio signal channels; and an audio reproducer for reproducing the localized virtual sound source signal.

A method and device are provided for determining a reproduction position of a source of sound for audio-visual reproduction of a film scene from a plurality of individual pictures with regard to a reproduction surface having a predetermined width, and with regard to a projection source having a projection reference point. A recording position of the source of sound, a camera position during recording, and an aperture angle of the camera during recording are obtained and the determined recording position is transformed to a camera coordinate system. A reproduction position for the source of sound is calculated and used to produce sound-source positioning in a reproduction room using wave-field synthesis methods.