Dts, Inc.

Hewlett-packard Development Company, L.P.

Future Wei Technologies, Inc.

Antonius A Kalker

Albert Chau

Michael M Goodwin

Gadiel Seroussi

Alan Hersh Karp

Elias Nemer

Jean-Marc Jot

Ashwin Deepak Swaminathan

Onur Gonen Guleryuz

Amir Said

Gregory William Cook

Themis George Katsianos

Zoran Fejzo

Guangji Shi

Daekyoung Noh

Jeffrey Kenneth Thompson

William Knox Carey

Jacek Stachurski

Vlad Ionut Ursachi

Petronel Bigioi

An audio signal encoding method is provided comprising: receiving first and second audio signal frames; processing a second portion of the first audio signal frame and a first portion of the second audio signal frame using an orthogonal transformation to determine in part a first intermediate encoding result; and processing the first intermediate encoding result using an orthogonal transformation to determine a set of spectral coefficients that corresponds to at least a portion of the first audio signal frame.

Audio coder window and transform implementations

A method of encoding an audio signal is provided comprising: applying multiple different time-frequency transformations to an audio signal frame; computing measures of coding efficiency across multiple frequency bands for multiple time-frequency resolutions; selecting a combination of time-frequency resolutions to represent the frame at each of the multiple frequency bands based at least in part upon the computed measures of coding efficiency; determining a window size and a corresponding transform size; determining a modification transformation; windowing the frame using the determined window size; transforming the windowed frame using the determined transform size; modifying a time-frequency resolution within a frequency band of the transform of the windowed frame using the determined modification transformation.

Audio coder window sizes and time-frequency transformations

A frequency domain long-term prediction system and method for estimating and applying an optimum long term predictor. Embodiments of the system and method include determining parameters of a single-tap predictor using a frequency-domain analysis having an optimality criteria based on spectral flatness measure. Embodiments of the system and method also include determining parameters of the long-term predictor by accounting for the performance of the vector quantizer in quantizing the various subbands. In some embodiments other encoder metrics (such as signal tonality) are used as well. Other embodiments of the system and method include determining the optimal parameters of the long-term predictor by accounting for some of the decoder operation. Other embodiments of the system and method include extending a 1-tap predictor to a k-th order predictor by convolving the 1-tap predictor with a pre-set filter and selecting from a table of such pre-set filters based on a minimum energy criteria.

System and method for long term prediction in audio codecs

Systems and methods discussed herein can provide three-dimensional audio virtualization with sweet spot adaptation. In an example, an audio processor circuit can be used to update audio signals for sweet spot adaptation based on information from at least one depth sensor or camera about a listener position in a listening environment.

Sweet spot adaptation for virtualized audio

An audio encoder can parse a digital audio signal into a plurality of frames, each frame including a specified number of audio samples, perform a transform of the audio samples of each frame to produce a plurality of frequency-domain coefficients for each frame, partition the plurality of frequency-domain coefficients for each frame into a plurality of bands for each frame, each band having a reshaping parameter that represents a time resolution and a frequency resolution, and encode the digital audio signal to a bit stream that includes the reshaping parameters. For a first band, the reshaping parameter can be encoded using a first alphabet size. For a second band, the reshaping parameter can be encoded using a second alphabet size different from the first alphabet size. Using different alphabet sizes can allow for more compact compression in the bit stream.

Encoding and decoding of digital audio signals using variable alphabet size

A transform-based codec and method with energy smoothing for mitigating vector quantization errors (such as 'birdies') during the encoding process. Embodiments of the codec and method use an encoder to apply in combination an orthogonal transformation and a vector permutation to frequency transform coefficients. In some embodiments the transformation is performed first followed by the permutation and in other embodiments the order is reversed. The order used is reversed at the decoder. A smoothing parameter containing the level of energy smoothing to be applied is passed from the encoder to the decoder and used by both to compute a transform matrix and an inverse transform matrix. In some embodiments the transform matrix is a fraction Hadamard matrix that is invertible, energy preserving, controllable, and stable.

Transform-based audio codec and method with subband energy smoothing

Lossy compression and transmission of a downmixed composite signal having multiple tracks and objects, including a downmixed signal, is accomplished in a manner that reduces the bit-rate requirement as compared to redundant transmission or lossless compression, while reducing upmix artifacts. A compressed residual signal is generated and transmitted along with a compressed total mix and at least one compressed audio objects. In the reception and upmix aspect the invention decompresses a downmixed signal and other compressed objects, calculates an approximate upmix signal, and corrects specific base signals derived from the upmix, by subtracting a decompressed residual signal. The invention thus allows lossy compression to be used in combination with downmixed audio signals for transmission through a communication channel (or for storage). Upon later reception and upmix, additional base signals are recoverable in capable systems providing multi-object capability (while legacy systems can easily decode a total mix without upmix).

Residual encoding in an object-based audio system

A method for designing microstructures for a light shaping reflector for use in a light field display is provided. A mathematical function is derived to reflect light uniformly from an incident light beam. Curved elements shaped by the mathematical function are combined to design the microstructures. The microstructures are formed in a reflective surface to provide the light shaping reflector for use in the light field display.

Surface microstructures for light shaping reflectors

To encode an arbitrary shape, a processor is configured to generate a rectangular block of transform coefficients by applying a discrete separable unitary transform to a rectangular boundary block of a video object. The boundary block includes a masked pixel and an unmasked pixel, the transform coefficients include a number of zero-valued transform coefficients greater than or equal to a number of masked pixels, and the transform coefficients include at least one non-zero-valued transform coefficient. The processor is also configured to generate an encoded output by compressing only the non-zero-valued transform coefficients.

Image transform zero coefficient selection and zero-skip transmission for arbitrary shape transform coding

An apparatus comprising a processor configured to receive a video teleconferencing image, wherein the video teleconferencing image has a background and at least one foreground, wherein the foreground has a boundary, determine the boundary of the foreground, overlay the boundary of the foreground with a drawing area, wherein the drawing area obscures the boundary, and replace the background of the image with a new background.

Visual conditioning for augmented-reality-assisted video conferencing

Various embodiments of the present invention are directed to methods and systems for distributing digitally encoded information. In one embodiment of the present invention, a licensee desiring to purchase digitally encoded information from a copyright owner posts collateral with a third party entity. The third party entity then provides authentication information to the licensee. The licensee transmits proof of knowledge of authentication information to the copyright owner. The copyright owner sends proof of the licensee's knowledge of authentication information and digital media to the third-party entity. The third-party entity embeds the authentication information in the digitally encoded information, and delivers the digitally encoded information with embedded authentication information to the licensee.

Methods and systems for distributing digitally encoded information

Embodiments of the present invention pertain to determining whether a digital rights management system's native license is valid. According to one embodiment, a value of a decision indicator is accessed at a digital rights management system. The decision indicator is set by a trusted entity other than the digital rights management system because the digital rights management system does not have sufficient information to determine how to set the decision indicator. The value of the decision indicator is used at the decision rights management system to determine whether the native license associated with the digital rights management system is valid.

Determining whether a digital rights management system's native license is valid

A method for controlling transfer of data is provided. The method includes accessing data at a first device and accessing a time attribute associated with the data at the first device. The method further includes comparing the time attribute to a data transfer time threshold and in response to the time attribute associated with the data at the first device is less than the data transfer time threshold, the method further includes restricting access of the data at a second device.

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Carmel, CA, United States of America

Antonius A Kalker