A powerline communications device comprises a powerline communications interface and at least one other communications interface configured to communicate over a computing network. The powerline communications interface is further configured to receive electrical power. The computing network may comprise mediums including powerlines, telephone lines, and/or coaxial cables. In some embodiments, the powerline communications interface may communicate with a network apparatus, such as a personal computer, via an Ethernet interface. The powerline interface, the telephone line interface, and/or the coaxial cable interface may all be associated with the same media access control (MAC) address. The powerline communications device may receive a message via a first medium and repeat the message via a second medium based on a quality of service (QoS) metric. In some embodiments, the powerline communications device may communicate using multiple frequency bands.

Multi-wideband communications over multiple mediums

A client device receives a broadcast content signal containing an interactive identifier over a managed network. The interactive identifier may be a trigger that is included in a header or embedded within the digital video data. In response to identification of the trigger, the client device sends a user request for interactive content over an unmanaged network. For example, the managed network may be a one-way satellite television network, IP-television network or cable television network and the unmanaged network may be the Internet. The client device switches between receiving data from the managed network to receiving data from the unmanaged network. Video encoding parameters of the interactive content are varied based on detected variations in the audio transmission bandwidth.

Providing Television Broadcasts over a Managed Network and Interactive Content over an Unmanaged Network to a Client Device

An audio signal processing apparatus includes: a division section that divides at least two or more channel audio signals into components in a plurality of frequency bands; a phase difference calculation section that calculates a phase difference between the two or more channel audio signals at each the frequency band; a level ratio calculation section that calculates a level ratio between the two or more channel audio signals at each the frequency band; a sound image localization estimation section that estimates, based on the level ratio or the phase difference, sound image localization at each the frequency band; and a control section that controls the estimated sound image localization at each the frequency band by adjusting the level ratio or the phase difference

Audio signal processing apparatus, audio signal processing method, and audio signal processing program

An acoustic echo canceller system having a filter with high suppression performance of acoustic echo, generated by using microphone array having a plurality of microphone elements, judging a band where only a speaker sound is present, based on phase difference among microphones, and carrying out adaptation of an adaptive filter for only such a band.

Acoustic echo canceller system

The present invention proposes a new method and apparatus for the improvement of digital filterbanks, by a complex extension of cosine modulated digital filterbanks. The invention employs complex-exponential modulation of a low-pass prototype filter and a new method for optimizing the characteristics of this filter. The invention substantially reduces artifacts due to aliasing emerging from independent modifications of subband signals, for example when using a filterbank as an spectral equalizer. The invention is preferably implemented in software, running on a standard PC or a digital signal processor (DSP), but can also be hardcoded on a custom chip. The invention offers essential improvements for various types of digital equalizers, adaptive filters, multiband companders and spectral envelope adjusting filterbanks used in high frequency reconstruction (HFR) systems.

Aliasing reduction using complex-exponential modulated filterbanks

An apparatus having a band-separating filter bank for separating a digital signal into a plurality of sub-band signals, to be processed or transmitted, and a band-combining filter bank for subsequently combining the resultant sub-band signals into a single digital signal, wherein each of the band-separating filter bank and band-combining filter bank incorporates a FIR low pass filter having an asymmetric impulse response, as the prototype filter of the filter bank. A significant reduction can thereby be achieved in the amount of overall group delay that results from the processing performed by these filter banks.

Digital signal sub-band separating / combining apparatus achieving band-separation and band-combining filtering processing with reduced amount of group delay

An input digital audio signal is divided into sub-band signals in respective sub-bands. Scale factors of the respective sub-bands are determined on the basis of the sub-band signals for every frame. Calculation is made as to differences between the determined scale factors for a first frame and the determined scale factors for a second frame preceding the first frame. Absolute values of the calculated scale-factor differences are calculated, and data representative of the calculated absolute values are generated. The data representative of the calculated absolute values are encoded into data of a Huffman code. Sign bits are generated which represent signs of the calculated scale-factor differences. The sub-band signals are quantized in response to the determined scale factors for every frame to generate quantized samples of the sub-band signals. The Huffman-code data, the generated sign bits, and the quantized samples of the sub-band signals are combined into a bit stream.

Method and apparatus for sub-band coding and decoding

PROBLEM TO BE SOLVED: To reduce the delay quantity of a system by adopting an FIR low pass filter where impulse responses become asymmetric for a basic filter and reducing group delay. SOLUTION: A PCM digital signal x(n) is inputted to a band division filter bank 001. Band division filters H0 to HM-1 010 to 01n execute convolution operation by each band. Down samplers 020 to 02n execute thinning. A prescribed signal processing is executed on a thinned signal by a processing 003. In a band synthesis filter bank 002, up samplers 040 to 04n execute an interpolation processing and band synthesis filters F0 to FM-1 030 to 03n execute the convolution operation by each band. An adder 004 adds the signals, and the signal is outputted as a reproduced PCM digital signal y(n). The filters H0 and F0 are basic filters, and an FIR low-pass filter where impulse responses are asymmetric is used.

Low delay sub-band division and synthesis device

An audio signal encoding method, an audio signal decoding method, a transmitter, a receiver, and a wireless microphone system, wherein a high compression efficiency can be achieved with a high quality and a low delay maintained. There are included a sub-band dividing filter bank (4a) for dividing an audio signal into a plurality of sub-bands and down-sampling them to produce a plurality of sub-band signals; LD-CELP quantizers (20a-20d) for encoding, based on LD-CELP, the plurality of sub-band signals; and a multiplexer (4c) for producing a bitstream from the encoded sub-band signals.

Audio signal encoding method, audio signal decoding method, transmitter, receiver, and wireless microphone system

The present invention provides a hearing aid capable of detecting contact vibration noise from a sound collecting signal. A hearing aid (100) is provided with two microphones (110-1, 110-2), a vibration component extracting unit (120) which extracts from sound collecting signals respectively obtained by the two microphones (110-1, 110-2) an uncorrelated component between these two sound collecting signals as a vibration component for each frequency band, a vibration noise identifying unit (130) which determines whether or not a contact noise occurs on the basis of the vibration component for each frequency band extracted by the vibration component extracting unit (120), an acoustic signal processing unit (140) which, when generating an acoustic signal by hearing aid processing of the above-mentioned two sound collecting signals, processes the acoustic signal depending on the presence or absence of the occurrence of the contact vibration noise, and a receiver (150) which converts the acoustic signal to sound.

Yutaka Banba

Papers

Digital signal sub-band separating / combining apparatus achieving band-separation and band-combining filtering processing with reduced amount of group delay

Method and apparatus for sub-band coding and decoding

Low delay sub-band division and synthesis device

Audio signal encoding method, audio signal decoding method, transmitter, receiver, and wireless microphone system

Hearing aid and method of detecting vibration