Dts, Inc.

Dolby Laboratories Licensing Corporation

Roger Wallace Dressler

Pierre-Anthony Stivell Lemieux

Michael C Ward

Jean-Marc Jot

Michael D Ward

Alan D Kraemer

Craig C Todd

Rhonda J Wilson

Kenneth James Gundry

Douglas E Mandell

Steven Joseph Venezia

John Iles

Steven Venezia

A bass management system and method for mitigating bass management errors by using explicit information available in the object audio rendering process and deriving the correct subwoofer contribution for each audio object. Embodiments of the bass management system and method are used to maintain the correct balance of the bass reproduced by the subwoofer relative to the sound coming out of the other speakers. The system and method are useful for a variety of different speaker configurations, including speaker configurations having different speaker sub-zones. Power-normalized gain coefficients for each speaker are combined and the power of the combined gain coefficients is computed and used to obtain a power-preserving subwoofer contribution coefficient. This subwoofer contribution coefficient is applied to the bass portion of the audio signal and audio objects to determine the contribution of a particular subwoofer.

Bass management for object-based audio

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.

System for dynamically creating and rendering audio objects

The invention relates to downmixing techniques by which output audio signals are obtained from input audio signals partitioned into subgroups. A variable common gain limiting factor is applied to all downmix coefficients that govern the contributions from the input signals in a subgroup. While preserving the proportions between signal values within a subgroup, the invention makes it possible to limit the gain of different input signal subgroups to different extents, so that relatively more perceptible signals can be limited relatively less. It then becomes possible to achieve a consistent dialogue level while transitioning in a less perceptible fashion between signal portions with and without gain limiting. Embodiments of the invention include a method, a mixing system and a computer-program product.

Downmix limiting

Methods and systems of reproducing object-based audio are disclosed. In some embodiments, vector base amplitude panning (VBAP) is used for playing back an object's audio. Using the positioning of sound reproduction devices and object's location information, rendering can determine which sound reproduction devices are used for playing back the object's audio. For example, a triangle in which the object is positioned at a given time can be identified. The triangle can have sound reproduction devices as vertices, and the object's audio can be rendered on the sound reproduction devices corresponding to the vertices of the triangle. In some embodiments, ambiguities associated with VBAP-based rendering are identified and resolved.

Object-based audio system using vector base amplitude panning

A single control determines both volume and the degree of compression in the reproduction of motion picture soundtracks. For some settings of the control, compression or limiting reduces the highest levels on a movie soundtrack, leaving the dialogue level substantially unchanged, thus removing the reason for complaints from the audience without the danger of making the dialogue too quiet for intelligibility.

Volume and compression control in movie theaters

The invention relates generally to transmitting and receiving multiple channels of information, particularly audio information which represents a multidimensional sound field. More particularly, the invention relates to devices and methods which provide signals that are compatible with multi-channel receivers and with matrix decoders such as the decode MP-Matrix used for many motion picture soundtracks. In a multi-channel transmitter, a network prepares intermediate signals which are encoded by signal analysis processors into a signal for subsequent transmission or storage. In a multi-channel receiver, information extracted from the received encoded signal is combined in a network and processed by signal synthesis processors to provide output signals which are compatible with a matrix decoder.

Multi-channel transmitter/receiver system providing matrix-decoding

The decoder of this invention decodes at least two channel signals in a directional information system where one or more input signals containing directional information have been encoded into the two or more channel signals. The decoder generates a first control signal substantially proportional to the logarithm of the ratio of the amplitudes of two of the channel signals to detect, as between two of the channel signals, whether the amplitude of one signal dominates that of the other. The decoder also generates a second control signal substantially proportional to the logarithm of the ratio of the amplitudes of the sum and the difference between two of the channel signals to detect the dominant signal in terms of amplitude. The decoder includes a matrix means responsive to the two or more channel signals and the two control signals for generating a number of output signals according to an algorithm. The control signals generated are used to steer the directional information systems in such manner through the matrix means that the directional effects of the output signals are enhanced. The matrix means generates three directional control signals from the two control signals.

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Bend, CA, United States of America

Roger Wallace Dressler