Abstract: A transceiver includes: a TV signal receiving unit for generating a first audio signal from a received broadcast wave; a decoder for decoding a reception signal received from the transceiver, to generate a second audio signal; an adding unit for transmitting the second audio signal to a speaker or adding up and transmit, to the speaker, the first audio signal and the second audio signal, and for outputting a reference signal; and an echo canceller for estimating a pseudo echo component from the reference signal, and cancels the pseudo echo component in a picked-up signal picked up by microphone a sound outputted from the speaker. The adding unit, when the TV signal receiving unit receives the broadcast wave, adds and transmits, to the speaker, the first audio signal and the second audio signal, and outputs a signal resulting from the addition as the reference signal to the echo canceller.

Abstract: A transceiver includes: a TV signal receiving unit for generating a first audio signal from a received broadcast wave; a decoder for decoding a reception signal received from the transceiver, to generate a second audio signal; an adding unit for transmitting the second audio signal to a speaker or adding up and transmit, to the speaker, the first audio signal and the second audio signal, and for outputting a reference signal; and an echo canceller for estimating a pseudo echo component from the reference signal, and cancels the pseudo echo component in a picked-up signal picked up by microphone a sound outputted from the speaker. The adding unit, when the TV signal receiving unit receives the broadcast wave, adds and transmits, to the speaker, the first audio signal and the second audio signal, and outputs a signal resulting from the addition as the reference signal to the echo canceller.

Abstract: An AV system includes a camera-equipped loudspeaker provided with a camera. The camera is united with a loudspeaker body, and captures an image in a direction in which the loudspeaker body outputs a sound. The recognition unit recognizes a location of a listener from an image of the camera, and detects an orientation of the loudspeaker body relative to the listener. The sound control unit performs signal processing on a given sound signal for generating an output signal, and outputs the output signal as an acoustic signal to the loudspeaker body.

Abstract: A sound image control device filters transfer functions H3 and H1 indicating transfer characteristics of a sound from an acoustic transducer (8) to entrances to respective ear canals (1) and (2) as well as filtering transfer functions H4 and H2 from an acoustic transducer (9) to the entrances to the respective ear canals (1) and (2) and generates second transfer functions H6 and H5 indicating transfer characteristics of a sound to the entrances to the respective ear canals (1) and (2) from a target sound source (11) at a location different from the sound sources, the sound image control device being equipped with correction filters (13) and (14) that (i) store characteristic functions E1 and E2 for performing filtering operations on the first transfer functions H1, H2, H3, and H4 and (ii) generate the second transfer functions H5 and H6 from the first transfer functions H1, H2, H3, and H4 using such characteristic functions E1 and E2.

Abstract: An audio encoder, generating a stereo signal based on a multi-channel signal, includes a downmix unit for downmixing a multi-channel signal exceeding two channels to a two-channel stereo signal, a first coding unit for generating a first coded signal by coding the downmixed stereo signal, a second coding unit for generating a second coded signal by coding information to restore the downmixed stereo signal to a multi-channel signal, a code size calculating unit for calculating a code size of the second coded signal, and a first multiplexing unit for multiplexing the calculated code size in either the first coded signal or the second coded signal. Accordingly a decoder is able to easily extract a coded signal of the multi-channel signal based on the code size, and the decoder reproducing only the downmixed signal can be configured inexpensively.

Abstract: A distribution system includes a distribution server device, an acquisition device, and an audio reproduction device, and distributes a program for decoding encoded audio data. The distribution server device sends the program for decoding the encoded audio data. The acquisition device is connected to the distribution server device via a network, and acquires the program and stores it in a removable memory unit. The audio reproduction device decodes the encoded audio data using the program stored in the removable memory unit, and outputs sounds.

Abstract: First and second coefficients are fed into a Fast Fourier Transform unit through real number input and imaginary number input portions thereof, respectively, to perform the Fast Fourier Transform of the entered first and second coefficients, thereby producing a frequency-domain coefficient vector. The Fast Fourier Transform of an input signal is performed to transform the input signal into a frequency-domain signal vector. Thereafter, the transformed signal vector is multiplied by the coefficient vector for each element, thereby providing a multiplication result. The Inverse Fast Fourier Transform of the multiplication result renders real number output and imaginary number output portions of the inverse transformation result as first and second series of output signals, respectively.

Abstract: An audio encoder, generating a stereo signal based on a multi-channel signal, includes a downmix unit (100) for downmixing a multi-channel signal exceeding two channels to a two-channel stereo signal, a first coding unit (101) for generating a first coded signal by coding the downmixed stereo signal, a second coding unit (102) for generating a second coded signal by coding information to restore the downmixed stereo signal to a multi-channel signal, a code size calculating unit (103) for calculating a code size of the second coded signal, and a first multiplexing unit (104) for multiplexing the calculated code size in either the first coded signal or the second coded signal. Accordingly a decoder is able to easily extract a coded signal of the multi-channel signal based on the code size, and the decoder reproducing only the downmixed signal can be configured inexpensively.

Abstract: A signal processing apparatus includes a decoder for decoding a stream signal so as to generate a digital audio signal of a low frequency effect channel and digital audio signals of first through n'th (n?2) channels; an adder section for adding the digital audio signal of the low frequency effect channel and the digital audio signal of a specified channel among the first through n'th channels, so as to generate an addition signal; an n number of D/A conversion sections for converting the digital audio signals of the first through n'th channels, excluding the digital audio signal of the specified channel, and the addition signal into n types of analog audio signals; a first signal processing section for generating a digital audio signal of the low frequency effect channel; and a second signal processing section for generating an analog audio signal of the specified channel.

Abstract: The sound image control device filters transfer functions H3 and H1 indicating transfer characteristics of a sound from an acoustic transducer (8) to entrances to respective ear canals (1) and (2) as well as filtering transfer functions H4 and H2 from an acoustic transducer (9) to the entrances to the respective ear canals (1) and (2) and generates second transfer functions H6 and H5 indicating transfer characteristics of a sound to the entrances to the respective ear canals (1) and (2) from a target sound source (11) at a location different from the sound sources, the sound image control device being equipped with correction filters (13) and (14) that (i) store characteristic functions E1 and E2 for performing filtering operations on the first transfer functions H1, H2, H3, and H4 and (ii) generate the second transfer functions H5 and H6 from the first transfer functions H1, H2, H3, and H4 using such characteristic functions E1 and E2.

Abstract: A sound reproduction device of the present invention includes: a first loudspeaker; a second loudspeaker; a first loudspeaker drive section for driving the first and second loudspeakers, the first loudspeaker drive section drives the first and second loudspeakers at substantially the same phase in a first frequency band, and the first loudspeaker drive section drives the first and second loudspeakers at substantially inverse phase and substantially different amplitude levels in a second frequency band higher than the first frequency band.

Abstract: A coding device includes: a decoder for decoding a first stream signal in which a first video stream including a first video stream information generated by coding a first video signal and a first audio stream including a first audio stream information generated by coding a first audio signal are multiplexed; and a re-encoder for generating, based on the decoded first stream signal, a second video stream including a second video stream information having a bit rate lower than the first video stream information and a second audio stream including a second audio stream information having a bit rate lower than the first audio stream information, and multiplexing the second video stream is and the second audio stream to generate a second stream signal.

Abstract: A reproduction apparatus includes a read section for reading a first data unit from a recording medium having the first data unit recorded thereon; a communication section for receiving a second data unit in accordance with a communication condition with a server; a synthesis section for, when the communication section cannot receive the second data unit in accordance with the communication condition, outputting the first data unit as a first output data unit, and when the communication section can receive the second data unit in accordance with the communication condition, synthesizing the first data unit and the second data unit so as to generate a synthesis data unit and outputting the synthesis data unit as a second output data unit; and a reproduction section for reproducing the first output data unit and the second output data unit.

Abstract: First and second coefficients are fed into a Fast Fourier Transform unit through real number input and imaginary number input portions thereof, respectively, to perform the Fast Fourier Transform of the entered first and second coefficients, thereby producing a frequency-domain coefficient vector. The Fast Fourier Transform of an input signal is performed to transform the input signal into a frequency-domain signal vector. Thereafter, the transformed signal vector is multiplied by the coefficient vector for each element, thereby providing a multiplication result. The Inverse Fast Fourier Transform of the multiplication result renders real number output and imaginary number output portions of the inverse transformation result as first and second series of output signals, respectively.

Abstract: This invention relates to a signal transmission apparatus and a signal transmission method both for transmitting a plurality of pieces of encoded audio information having a plurality of sampling frequencies of F or 1/N×F, which are encoded by the same encoding method, via a digital interface to a signal reception apparatus.

Abstract: An encoding device includes an encoding section for generating hit streams having a variable frame length from an input audio signal, a maximum frame length of the bit streams being fixed; a storage section for storing the bit streams generated by the encoding section; and a transfer section for transferring the bit streams at a prescribed transfer rate. The storage section includes a buffer having a capacity corresponding to at least a value which is obtained by subtracting an amount of the bit streams transferable in one frame time period at a minimum possible transfer rate from a value of twice the maximum frame length.

Abstract: According to the data amount and the nature of a video stream and an audio stream included in a program stream which is to be decoded, an audio and video processing apparatus performs processing while allocating higher priority to one or the other of the video and audio streams. Without any increase in circuit complexity or clock speed, this apparatus can reproduce streams in at least two formats, in which the ratios of the amounts of encoded signal data and of the amounts of calculation required for decoding for the video and the audio are very different.

Abstract: An audio decoding apparatus is provided for receiving a bit stream on a block-by-block basis, decoding one block of the bit stream to form decoded audio data for a plurality of channels, and storing the decoded audio data for each of the plurality of channels in a memory device, thereby down-mixing the decoded audio data for each of the plurality of channels. The audio decoding apparatus includes an operation section for down-mixing the decoded audio data for each of the plurality of channels corresponding to a first block of the bit stream in the memory section while a second block of the bit stream is decoded.

Abstract: When, through a multi-speaker of a DVD audio system, signals are recorded/reproduced using a sampling frequency different for every channel, the quantity of calculation of a filter circuit is reduced. Up-sampling information about whether or not the sampling is carried out before the up-sampling by up-sampling means (2a, 2b) is acquired by up-sampling information detecting means (6). The signal up-sampled is filtered by a halfband filter circuit (3), subjected to loss-less compression, and recorded on a recording medium (8).

Abstract: A decoding circuit, for receiving a bit stream including an encoded audio signal and header information used for-decoding the encoded audio signal, and decoding the encoded audio signal based on the header information, includes a header analysis section for outputting at least one decoding parameter obtained from the header information and decoding parameter change information indicating whether or not the at least one decoding parameter has been changed; a signal processing section for decoding the encoded audio signal, based on the at least one decoding parameter, into a decoded signal and outputting the decoded signal; an automatic mute processing section for executing automatic mute on the decoded signal after the at least one decoding parameter is changed; and an output section for outputting the decoded signal output from the automatic mute processing section.