Niigata Seimitsu Co., Ltd.

Other

Agency of Industrial Science and Technology

Alpine Electronics, Inc.

Ministry of International Trade & Industry

Kazuo Toraichi

Ryoichi Mori

Yukio Koyanagi

Kouichi Wada

Masaru Kamada

Koichi Endo

Nobuyuki Otsu

Takashi Tokuyama

Youichi Hashimoto

Motomu Suzuki

An image processing circuit capable of carrying out high-speed processing and improving the horizontal and vertical resolutions even with its simple structure. The pixel values a to i of a total of nine pixels, three pixels in the horizontal direction along a scanning line by three pixels in the vertical direction in which the line and adjacent lines are abreast, are extracted by a pixel value extracting section. The pixel values Ato Aof four pixels Qto Qgenerated additionally around the center pixel Pare determined by calculation by a pixel value calculation section. These pixel values are outputted in units of one scanning line by correlating them with two scanning lines by a pixel value output section.

Image processing circuit

A digital-to-analog converter for generating output waveforms with less distortion without the need for high-speed components. The digital-to-analog converter comprises a D/A converter, four voltage holding sections, four step function waveform generators, a voltage summing section, two integrators and a timing controller. The voltages corresponding to four sequential digital data inputs are held in the voltage holding sections, respectively, and the step function generators generate step function waveforms at the voltage levels corresponding to the held voltages. The voltage summing section combines the step function waveforms generated in the step function waveform generators, and two integrators integrate this combined waveform two times, thus producing a continuous analog voltage composed of the input digital data.

Digital-to-analog converter with plural voltage holding sections, plural step function generators, voltage summing section and integrator

A data interpolating system by which the operating quantity can be decreased and no truncation error is produced. A data processor comprises a discrete value extracting section a sampling function operating section and a convolution operating section so as to perform interpolation between discrete values. The discrete value extracting section extracts just previous four value from successively inputted discrete data, and the sampling function operating section calculates, when the data interpolating position is specified, the value of the interpolating position based on the distances between the data interpolating position and the discrete values by using a sampling function of local support which can be differentiated only once over the whole region. The convolution operating section multiplies the values of the four sampling functions by the discrete values, and adds up the products, thus performing convolution operation and outputting the interpolation value.

Data interpolating system

A data interpolating method capable of reducing an operation volume without the occurrence of a truncation error. Each of four step function generators generates a preset step function. Multipliers each multiply step function values output from relative step function generators by discrete data values held cyclically in data holding sections. An adding unit adds together the multiplied results output from respective multipliers in response to the respective four discrete data and the added values is integrated twice by integrators, an interpolation value between the discrete data being then output from the second-stage integrator.

Data interpolation method

A digital-analog converter for producing less distorted output waveforms without the need for an increase in the operating speed of components. A D/A converter comprises a memory , an address counter , a B spline function generation circuit , four sampling function generation circuits , three delay circuits , four amplifiers , and three adding circuits and . Four items of digital data supplied one after another in the predetermined time interval T are stored in the memory . The gain of each of the four amplifiers is set according to the corresponding digital data. The four sampling function generation circuits generate signal waveforms of the sampling function, which appear individually in points a time T away from one another. The signal waveforms are amplified in the amplifier and added to produce an analog signal associated with the interpolation value.

Digital to analog converter using B spline function

A digital-to-analog converter for generating output waveforms with less distortion without the need for high-speed components. The digital-to-analog converter comprises four data holding sections, four step function generators, an adding section, a D/A converter, two integrators and a timing controller. Four digital data successively inputs are held in the data holding sections, respectively, and the step function generators generate step function whose values corresponding to the held data. The adding section sums the step functions generated in the step function generators, and the D/A converter generates the analog stepwise voltage corresponding to the summed value. The two integrators integrate this combined waveform two times, thus producing a continuous analog voltage that connects the input digital data smoothly.

Digital to analog converter with step voltage generator for smoothing analog output

A sampling function generator capable of providing continuous output corresponding to a sampling function. The sampling function generator comprises a B spline function generation circuit delay circuits and inverting amplifiers and and adding circuits and The B-spline function generation circuit continuously produces signal waveforms according to a third order B spline function. After delayed by predetermined time or attenuated to 1/4 amplitude and inverted, the signal waveforms are combined in the adding circuits and to form a signal waveforms of a sampling function that is differentiable once over the range and has values of local support.

Sampling function generator

A method of compressing inputting two-dimensional object, compressing the two-dimensional data in a short time to a small amount of data and reproducing in any size at any position. This invention reads two dimensional object, e.g. characters, figures, drawings or Illustrations optically, extracts peripheral points from a binary image, approximates the peripheral lines by Fluency functions, reckons curvatures at all points, and finds joints. The peripheral points series are divided by the joints. The lines between two neighboring joints are approximated by straight lines, arcs and free curves in this order. The free curves are approximated by linear combinations of Fluency functions. Adoption of joints greatly alleviates the quantity of data. Approximation by Fluency functions heightens the quality of the reproduced objects.

Apparatus and method for inputting, compressing and outputting

A video signal processing system improves the image quality displayed in a CRT or printed by a video printer. In order to produce natural and fine video signals, pixel data corresponding to an intermediate position between two neighboring pixels, are produced from pixel data of the neighboring two pixels. The pixel data corresponding to the intermediate position is produced by a convolution operation with respect to the pixel data of the two neighboring pixels and a quantized value of an impulse response signal.

Video signal processing system for producing intermediate pixel data

A signal modification circuit receives an input signal and produces an output having a modified characteristic. When the signal modification circuit is embodied in an audio circuit receiving an analog audio signal having a first variant level at its input, the audio circuit produces an output signal having a second variant level in which a frequency characteristic in a high frequency range is modified so that the second variant level decreases in accordance with a function of l/fm (f being frequency and m being an integer determined depending upon the nature of the audio signal) relative to the first variant level while being trapped in selected discrete frequencies. For this purpose a combination of a low-pass filter and a plurality of trap filters connected in series with one another, or a combination of a low-pass filter and a plurality of band-pass filters connected in parallel to one another. Instead, a convolution operating circuit is used which performs a convolution operation between an input digital signal and a unitary impulse response signal. In accordance with such audio circuit, the local position of musical sounds is stabilized and the articulation of spoken words is improved. The signal modification circuit according to the invention is also applicable to digital-to-analog converting circuit.

Signal modification circuit

A data generator generates digital data at a sampling time interval .sub..DELTA. T (sampling frequency f.sub.s =1/.DELTA.T), and the three latest items of digital data V.sub.-1, V.sub.0, V.sub.+1 are repeatedly latched successively in three latch circuits every 3.multidot..sub..DELTA. T. A pulse response signal generator outputs unit pulse response signals of period 3.multidot..sub..DELTA. T at the time interval .multidot..sub..DELTA. T, and three multiplying-type DA converters multiply these three unit pulse response signals .phi..sub.0 (t+.sub..DELTA. T), .phi..sub.0 (t), .phi..sub.0 (t-.sub..DELTA. T) by the digital data V.sub.-1, V.sub.0, V.sub.+1, respectively, at a speed of a.multidot.f.sub.s (a times in time .sub..DELTA. T). The outputs of these multiplying-type DA converters are combined into an analog signal S.sub.A, which is delivered as an output.

Digital-analog converter for converting digital audio signals

A continuous analog signal is produced by successively generating digital data V.sub.K (K=. . . , -4, -3, -2, -1, 0, 1, 2, 3, . . . ) every predetermined sampling period T, repeatedly generating, successively at a period 3T, signals .phi.(t+T), .phi.(t), .phi.(t-T), where a unit pulse response signal .psi.(t) is expressed by

Digital-analog converting method, and apparatus therefor

An image processor which can accurately and promptly obtain information about a ventricle of a living body, such as the boundary diagram, the volume, the centroid movement view and a three-dimensional view. An X-ray projection of a part to be diagnosed is quantized. The boundary and centroid of the part are obtained from the optimal ternary data using the variance of the gray-level of the image and the separation degree of a histogram. The volume and three-dimensional view of the part are obtained from this data using the gray-level method.

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Sayama, Japan

Kazuo Toraichi