Abstract: An audio output apparatus has a measuring circuit which measures the levels of at least two sound signals, a sound level adjusting module (a sound level adjusting circuit and a gain control circuit) which adjusts a sound level so as to equal the levels of the sound signals based on the levels measured at the measuring circuit, and an array speaker unit (a delay circuit, a multiplier, an adder, an amplifier and a speaker unit) which emits sounds in accordance with the sound signals outputted from the sound level adjusting module in different directivities respectively.

Abstract: An audio characteristic correction system adapted to an audio surround system in which a sound emitted from a directional speaker (an array speaker) is reflected on a wall surface or a sound reflection board so as to create a virtual speaker, at least one of frequency-gain characteristics, frequency-phase characteristics, and gain of an audio signal input to the directional speaker is corrected such that the sound reflected on the wall surface or the sound reflection board has desired audio characteristics at a desired listening position.

Abstract: Input audio signals are divided into low-frequency components and high-frequency components, both of which are subjected to delay processing in correspondence with desired positions of focal points with respect to speaker units respectively. Delayed low-frequency components are further subjected to weighting using a first window function. Delayed high-frequency components are subjected to weighting using a second window function (e.g., a Hamming window function). Weighted high-frequency components and weighted low-frequency components are added together with respect to the speaker units, which are thus driven respectively. The first window function applied to low-frequency components is made moderate in weighting in comparison with the second window function applied to high-frequency components; thus, it is possible to reduce differences of sound directivities between low-frequency components and high-frequency components of audio signals.

Abstract: An array speaker system, in which a plurality of speaker units are arranged in an array and are supplied with signals having prescribed time differences so as to perform directivity control on audio signal beams emitted therefrom, includes a delay memory (e.g., a shift register) having plural delay taps for outputting an input signal thereof with different delay times, which are set in units of the sampling period, and an interpolation processing means for performing interpolation processing on the output of the delay memory. A control means calculates distances between a focal point of audio signal beams and the speaker units so as to produce delay times, and it also sets interpolation coefficients with respect to the speaker units respectively. The interpolation processing means performs linear interpolation on the outputs of the delay memory. Alternatively, an FIR low-pass filter is formed using the delay memory and interpolation processing means, thus performing delay and interpolation processing.

Abstract: In a directional speaker control system for realizing good sound localization by correcting the directivity of a directional speaker, adapted to an audio surround system in which a desired sound is reflected on a wall surface or a sound reflection board so as to produce a virtual speaker, a first directional speaker emits a first sound toward the wall surface or sound reflection board so that the reflected sound reaches a prescribed listening position, and a second directional speaker emits a second sound, which comes to have an inverse phase with respect to an audio element of the first sound reaching the listening position directly, toward the listening position. Thus, it is possible to adequately dampen the audio element (particularly, low-frequency components) emitted directly toward the listening position from the first directional speaker; hence, it is possible to realize good sound localization.

Abstract: An optical disk recording apparatus operates on an optical disk having circular tracks which are provisionally written with an index signal used for securing a constant linear velocity of the optical disk from an innermost circular track to an outermost circular track, and records data along the circular tracks at different linear densities on different annular zones of the optical disk. In the apparatus, a disk drive section rotates the optical disk while synchronizing the index signal successively read from the rotated optical disk with a predetermined reference clock signal to thereby maintain the constant linear velocity of the circular tracks. A clock generating section multiples or divides the reference clock signal by different rates to generate different writing clock signals in correspondence to the different annular zones of the optical disk.

Abstract: An optical disk recording apparatus operates on an optical disk having circular tracks which are provisionally written with an index signal used for securing a constant linear velocity of the optical disk from an innermost circular track to an outermost circular track, and records data along the circular tracks at different linear densities on different annular zones of the optical disk. In the apparatus, a disk drive section rotates the optical disk while synchronizing the index signal successively read from the rotated optical disk with a predetermined reference clock signal to thereby maintain the constant linear velocity of the circular tracks. A clock generating section multiples or divides the reference clock signal by different rates to generate different writing clock signals in correspondence to the different annular zones of the optical disk.

Abstract: A visible image is formed on an optical disk by using an optical disk recording apparatus that forms a pit with a length defined by recording data (EFM-modulated data) by applying a laser beam onto the optical disk. At least a part of the recording data are replaced with the visible image forming data to generate the recording data containing visible image forming data. When the recording data containing the visible image forming data are recorded on the optical disk, the visible image forming data are extracted from the recording data to act as a gate signal. The visible image is formed by forming a pit defined by the recording data in an area of the gate signal.

Abstract: An optical disk recording apparatus operates on an optical disk having circular tracks which are provisionally written with an index signal used for securing a constant linear velocity of the optical disk from an innermost circular track to an outermost circular track, and records data along the circular tracks at different linear densities on different annular zones of the optical disk. In the apparatus, a disk drive section rotates the optical disk while synchronizing the index signal successively read from the rotated optical disk with a predetermined reference clock signal to thereby maintain the constant linear velocity of the circular tracks. A clock generating section multiples or divides the reference clock signal by different rates to generate different writing clock signals in correspondence to the different annular zones of the optical disk.

Abstract: A visible image forming method is performed for forming a visible image on an optical disk by an optical disk recording apparatus, which is designed for applying a laser beam onto an optical disk according to first recording data of a predetermined format to form pits having lengths specified by the first recording data. First, a generating step is performed for generating second recording data by embedding image formation data of a visible image in a part of a predetermined format which is the same as predetermined for the first recording data. Second, an extracting step is performed for extracting the image formation data of the visible image from the second recording data of the predetermined format. Then, a forming step is performed for forming pits in the optical disk according to the extracted image formation data so as to form the visible image on the optical disk.

Abstract: An optical disk recording apparatus operates on an optical disk having circular tracks which are provisionally written with an index signal used for securing a constant linear velocity of the optical disk from an innermost circular track to an outermost circular track, and records data along the circular tracks at different linear densities on different annular zones of the optical disk. In the apparatus, a disk drive section rotates the optical disk while synchronizing the index signal successively read from the rotated optical disk with a predetermined reference clock signal to thereby maintain the constant linear velocity of the circular tracks. A clock generating section multiples or divides the reference clock signal by different rates to generate different writing clock signals in correspondence to the different annular zones of the optical disk.

Abstract: A digital signal processing circuit has a coefficient storing portion, a computing portion, a coefficient selection control portion and a coefficient transfer portion. The coefficient storing portion stores multiplier coefficients used for a convolution computation, in which a value of each multiplier coefficient can be arbitrarily changed. The computing portion stores a series of input data to be inputted thereto sequentially during certain period to be previously passed, so that the computing portion carries out the convolution computation on the series of input data by use of the multiplier coefficients. In addition, the coefficient selection control portion controls a selection of a data input/output manner, i.e., either a data first-in-first-out manner or a data circulation manner is selected. The coefficient transfer portion inputs the multiplier coefficients to the storing portion from a external device, or outputs the coefficients to the external device.

Abstract: A signal processing large scale integrated circuit for carrying out convolution calculations includes multiple delay stages serially connected to thereby form an input data path for a first input signal, a first calculation circuit wherein predetermined calculations are carried out using the output of each of the above mentioned delay stages and a second calculation circuit connected to a convolution path wherein predetermined calculations are carried out using the output of the above mentioned first calculation circuit and a second input signal output from another large scale integrated circuit. The problem of a prolonged delay when multiple LSI circuits are cascade-connected together is eliminated by outputting the first output signal from an intermediate delay element and supplying it as the input to the next stage large scale integrated circuit.