Dolby Laboratories

About: Dolby Laboratories is a company organization based out in Amsterdam, Netherlands. It is known for research contribution in the topics: Audio signal & Audio signal flow. The organization has 956 authors who have published 1726 publications receiving 29456 citations.

Method and apparatus for improving noise discrimination using enhanced phase difference value

Abstract: Noise discrimination in signals from a plurality of sensors is conducted by enhancing the phase difference in the signals such that off-axis pick-up is suppressed while on-axis pick-up is enhanced. Alternatively, attenuation/expansion are applied to the signals in a phase difference dependent manner, consistent with suppression of off-axis pick-up and on-axis enhancement. Nulls between sensitivity lobes are widened, effectively narrowing the sensitivity lobes and improving directionality and noise discrimination.

Loudness Modification of Multichannel Audio Signals

Abstract: Scaling, by a desired amount sm, the overall perceived loudness Lm of a multichannel audio signal, wherein perceived loudness is a nonlinear function of signal power P, by scaling the perceived loudness of each individual channel Lc by an amount substantially equal to the desired amount of scaling of the overall perceived loudness of all channels sm, subject to accuracy in calculations and the desired accuracy of the overall perceived loudness scaling sm. The perceived loudness of each individual channel may be scaled by changing the gain of each individual channel, wherein gain is a scaling of a channel's power. Optionally, in addition, the loudness scaling applied to each channel may be modified so as to reduce the difference between the actual overall loudness scaling and the desired amount of overall loudness scaling

Dual panel display with cross BEF collimator and polarization-preserving diffuser

Abstract: A display including an image-generating panel and at least one contrast-enhancing panel, a cross BEF collimator between a backlight and one of the panels, and a polarization-preserving diffuser (e.g., holographic diffuser) between the panels. Typically, the contrast panel is upstream of the image panel, and a reflective polarizer is positioned between the cross BEF collimator and contrast panel, with the reflective polarizer oriented relative to an initial polarizer of the contrast panel. Polarization of light transmitted by the reflective polarizer matches that transmitted by the initial polarizer. Collimated light propagating from the cross BEF collimator toward the contrast-enhancing panel is given a polarization bias by the reflective polarizer, which reflects incorrectly polarized light back toward the cross BEF collimator. Alternatively, the reflective polarizer may be positioned between the cross BEF collimator and the image-generating panel when the image-generating panel is upstream of the contrast-enhancing panel.

Content-based Video Signatures based on Projections of Difference Images

Abstract: We propose a novel video signature extraction method based on projections of difference images between consecutive video frames. The difference images are projected onto random basis vectors to create a low dimensional bitstream representation of the active content (moving regions) between two video frames. A sequence of these signatures serves to identify the underlying video content in a robust manner. Our experimental results show that the proposed video signature is robust to most common signal processing operations on video content such as compression, resolution scaling, brightness scaling.

Coded signal formatting for encoder and decoder of high-quality audio.

Abstract: An encoder applies a digital filterbank such as a transform or subband filterbank to an input signal to generate frequency subband information, encodes the resultant subband information using adaptive bit allocation to generate fixed-length values represented by fixed numbers of bits and variable-length values represented by variable numbers of bits, and formats the subband information into an encoded signal in which the fixed-length values are assembled into preestablished positions within the encoded signal. In response to an encoded signal including subband information represented by fixed-length values and variable-length values, a decoder extracts fixed-length values represented by fixed numbers of bits from preestablished positions within the encoded signal, extracts variable-length values represented by variable numbers of bits, wherein the variable numbers of bits are established in response to fixed-length values, and generates an output signal by applying an inverse filterbank to the extracted subband information.