Abstract: Methods and apparatus are provided in which a computed vector index (CVI) can be generated/computed based on an input value being searched for within an index vector of a lookup table. When the CVI is greater than a length of an index vector, the CVI can be re-computed to generate a re-computed vector index (RVI). When the value of the CVI is determined to be correct, or when the RVI is generated, an interpolation routine for a linearly indexed index vector can be executed using a presently computed vector index (e.g., either the CVI or the RVI) to determine an interpolated output value that corresponds to the input value. By contrast, when the value of the CVI is determined to be incorrect, an interpolation routine for a piecewise indexed index vector can be executed to determine the interpolated output value.

Abstract: Data rate conversion devices and methods are provided. A method for converting a first digital signal having a first sampling rate into a second digital signal having a sampling rate close to a predetermined second sampling rate comprises the following operations: when the ratio of the first sampling rate to the second sampling rate is a repeating infinite decimal, calculate at least two calibrating coefficient values and output the calibrating coefficient values according to a predetermined rule; conduct overflow operation on the output calibrating coefficient; and interpolate the first digital signal using the output calibrating coefficient and the result of the overflow operation to obtain the second digital signal such that during any period of a certain length along time axis, sampling times of the second digital signal equals to sampling times of the second sampling rate.

Abstract: A computer executable method of processing a representation of a modal interval polynomial is provided. A representation of a modal interval polynomial is generally provided as input, more particularly, a representation comprising a modal interval function variable and an array of modal interval coefficients. Each modal interval linear interpolation of each of the modal interval coefficients of the array are recursively processed until a single modal interval coefficient remains in the array. For each iteration of the recursive processing, a modal interval linear interpolation operation is executed.

Abstract: The present invention relates to a method for resampling time series data and to a telemetric device configured to resample measured time series data. A method for resampling time series data comprises the following steps: determining a first time series 10 comprising a sequence of data points Pi; determining a variation V of the data points Pi within a selected sequence of data points, wherein the variation V is determined by determining linearly interpolated data points Qi for the data points Pi of the selected sequence and by determining a maximum absolute difference V between the data point value Pi and the corresponding interpolated data point value Qi for the data points of the selected sequence.

Abstract: The present invention relates to a blind adaptive filter for narrowband interference cancellation, which includes an adaptive filter, a delay unit coupled to the adaptive filter for generating a delayed signal with a predetermined delay length from the output signal of the adaptive filter, and an error calculation unit coupled to the adaptive filter and the delay unit. The error calculation unit compares the output signal from the adaptive filter and the delayed signal from the delay unit to extract error information, and feedback the first error information to the adaptive filter. The first error information is formed of a transfer function including a number of coefficients, and used to adjust the adaptive filter and remove interference in the next input signal. The disclosed technique is also applicable in wideband receivers, as well as resisting multiple strong narrowband interferences having a frequency sweep rate of tens of milliseconds.

Abstract: Methods and an apparatus are provided for interpolation of pixels in a pixel array having rows and columns of pixels. The apparatus includes a shift register array to shift pixel values of the pixel array, the shift register array including two or more shift registers; an interpolation filter array interconnected to the shift register array, the interpolation filter array including one or more interpolation filters; and a controller configured to provide pixel values in columns of the pixel array from the shift register array to respective interpolation filters in a first mode and configured to provide pixel values in rows of the pixel array from the shift register array to respective interpolation filters in a second mode. The controller may be configured to supply vertical sub-pixel values from the shift register array to the interpolation filters to generate diagonal sub-pixel values.

Abstract: A signal processing system includes a digital sample rate converter to convert a signal sampled at a first sampling frequency into a corresponding signal sampled at a second sampling frequency. In at least one embodiment, the sample rate converter includes a digital sample rate conversion filter. The digital sample rate conversion filter includes a digital filter that models a continuous time filter such as a low pass RC filter and generates filtered samples. The digital sample rate conversion filter also includes an interpolation filter that determines samples between the digital filtered samples. A sample selector selects the samples generated by the interpolation filter at the second sampling frequency. In at least one embodiment, the sample selector determines when to generate interpolated samples and the amount of time offset from an adjacent sample generated by the digital filter.

Abstract: An embedded control system capable of ensuring precision in arithmetic with data in the floating-point format and also avoiding a shortage of the storage area of a memory is provided. According to an embedded control system in the present invention, when discrete data in the floating-point format is stored in a read-only memory, the discrete data in the floating-point format is converted into data in a significand-reduced floating-point format before being stored. Here, a significand-reduced floating-point number is a number obtained by deleting low-order bits of the significand of a floating-point number. Further, an interpolation search is performed using discrete data, the discrete data in the significand-reduced floating-point format stored in the read-only memory is brought back to the discrete data in the floating-point format before an interpolation search being performed.

Abstract: A method for use in a digital frequency synthesizer, the method comprising phase to amplitude conversion of an output value of a phase accumulator in said synthesizer, said conversion being carried out as an approximation (y) of a phase value (x) which corresponds to said output amplitude value, the method being characterized in that the approximation comprises a combination of a linear interpolation value and a second order sinusoidal value, the second order sinusoidal value being used as an error term to correct for errors in the linear interpolation value.

Abstract: Methods for modeling a random variable with spatially inhomogenous statistical correlation versus distance, standard deviation, and mean by spatial interpolation with statistical corrections. The method includes assigning statistically independent random variable to a set of seed points in a coordinate frame and defining a plurality of test points at respective spatial locations in the coordinate frame. A equation for a random variable is determined for each of the test points by spatial interpolation from one or more of the random variable assigned to the seed points. The method further includes adjusting the equation of the random variable at each of the test point with respective correction factor equations.

Abstract: An audio data processing device and method includes selecting one multiple-S-curves, and running an interpolation arithmetic upon original points according to the selected multiple-S-curve. Selecting one multiple-S-curve includes selecting one of a plurality of S-curves corresponding to a current utilization ratio of a processor, obtaining audio data having a fixed length including sampling frequencies and the original points of the obtained audio data, and selecting the one multiple-S-curves corresponding to the selected S-curve and the obtained sampling frequencies.

Abstract: A method and circuit that gives a sequence pattern that represents directions of positive and negative transitions of the phase that continue over a predetermined number from a certain reference symbol to an adjoining next reference symbol; finds (heuristically) one or more interpolate symbols that meet conditions (such as standards for power spectra) of a predetermined frequency spectrum, i.e., band, and a predetermined (range of) amplitude with reference to the given sequence pattern; and stores the found sequence pattern and a phase value and an amplitude value corresponding to the found one or more interpolate symbols in a memory as a lookup table against the prepared memory area.

Abstract: A signal processing method that includes inputting sample values of a signal and considering the signal to have a plurality of portions. For each portion, a predetermined function is fitted to the sample values of that portion of the signal by calculating values of coefficients for that predetermined function. At least one statistical information function is evaluated for the signal to determine statistical information about the signal and the calculated coefficient values are used so that the form of the statistical information function has been determined for the predetermined function used to fit the signal portion and further includes using the statistical information obtained about the signal to process the signal.

Abstract: A noise reducing apparatus includes: a voice signal inputting unit inputting an input voice signal; a noise occurrence period detecting unit detecting a noise occurrence period; a noise removing unit removing a noise for the noise occurrence period; a generation source signal acquiring unit acquiring a generation source signal with a time duration corresponding to a time duration corresponding to the noise occurrence period; a pitch calculating unit calculating a pitch of an input voice signal interval; an interval signal setting unit setting interval signals divided in each unit period interval; an interpolation signal generating unit generating an interpolation signal with the time duration corresponding to the noise occurrence period and alternately arranging the interval signal in a forward time direction and the interval signal in a backward time direction; and a combining unit combining the interpolation signal and the input voice signal, from which the noise is removed.

Abstract: Method and systems are described for estimating signal impairments, in particular jitter that includes uncorrelated, non-periodic signal impairments. One system may take the form of an oscilloscope. The estimates may take the form of a probability density function (PDF) for uncorrelated signal impairments that has been modified to replace low probability regions with a known approximation and an extrapolation of the known approximation.

Abstract: The purpose of this invention is that the optimum approximation formula can be derived even if an analysis filter has non-linear characteristic in a discrete signal approximation system. The norm of source signal 1 is bounded. Analysis filters 2 of FIR filters yield the output signal that is expressed with polynomial of transformed source signal 1 through a unit filter. An interpolation function is calculated according to the filter characteristic based upon the multi-dimensional function transformed from the polynomial. The output signal of the analysis filter 2 is sampled after each constant interval to obtain a discrete signal. The approximation function of the power function of the source signal 1 is calculated with linear combination of the interpolation functions using the discrete signals as coefficients. The radical of this approximation function is calculated to derive the root approximation function of the source signal 1.

Abstract: A method for deformable registration of 2 digital images includes providing a pair of digital images, including a fixed image and a moving image, extracting a set of edge images from each image of the pair of images, each edge set being extracted at a different resolution, selecting a pair of edge images with a lowest resolution, determining a mapping from edge points of the fixed image to edge points of moving image using a geodesic thin plate spline interpolation, applying the mapping to a next higher resolution edge point image of the moving image, selecting a pair of edge images at a next higher resolution, where a moving edge image is the moving edge image to which the mapping has been applied, repeating the steps at a next higher resolution for all edge images in the set of edge images, and applying the mapping to an entire moving image.

Abstract: A method to increase the accuracy of the interpolation of railroad mileposts is disclosed. Based upon image data and data provided in customer track charts, reference points are selected along the track, and their location is verified using GPS data. Once verified, the locations of various points between the reference points are determined using mathematical interpolation.

Abstract: Multipurpose arithmetic functional units can perform planar attribute interpolation and unary function approximation operations. In one embodiment, planar interpolation operations for coordinates (x, y) are executed by computing A*x+B*y+C, and unary function approximation operations for operand x are executed by computing F2(xb)*xh2+F1(xb)*xh+F0(xb), where xh=x?xb. Shared multiplier and adder circuits are advantageously used to implement the product and sum operations for both classes of operations.

Abstract: A tool-path calculation apparatus for a numerical controlled system and a method for operating the same are applied to a CNC tool machine. The tool-path calculation apparatus includes an upper controller and a servo driver. Firstly, an interpreter is provided to interpret the tool paths to produce a plurality of executable instructions. Afterward, the executable instructions are sent from the upper controller to the servo driver through a serial communication interface and stored in a queue buffer. Finally, the executable instructions are received and calculated by a tool path calculator to produce a plurality of points along the tool paths.

Abstract: For controlling a motion sequence of a machine element, with which the control of the motion sequence of the machine element is carried out based on a functional relationship between a master shaft and a slave shaft, the functional relationship IS ascertained with consideration for several conditions of this motion sequence. The functional relationship includes at least one first section, which is defined by an nth-order polynomial, and at least one second section, which is at least partially separated from the first section, and which is defined by an ath-order polynomial. In this case, “a” is less than “n”.

Abstract: A color conversion apparatus includes a plurality of color conversion units configured to perform color conversion using a conversion table with different algorithms, a weighting unit configured to set weightings applied to the plurality of color conversion units, and a mixing unit configured to mix a plurality of color conversion results obtained by the plurality of color conversion units using the weightings calculated by the weighting unit.

Abstract: An image processing apparatus obtains color image data by performing an interpolation processing for an image signal output from a color image pickup element having color filters arranged like a mosaic, by using a filter. The apparatus includes an interpolation processing unit which selectively modifies an interpolation processing according to a kind of layout pattern of a spatial center position of gravity of each color component signal included the image signal in an image area to be interpolated, so that the spatial center position of gravity of each color component signal after the interpolation processing becomes identical in any layout pattern, if there are a plurality of kinds of layout pattern of a spatial center position of gravity of each color component signal included the image signal in an image area to be interpolated.

Abstract: An OFDM (Orthogonal Frequency Division Multiplexing) demodulator includes: an FFT (Fast Fourier Transform) circuit for performing a fast Fourier transform on an OFDM signal; a circuit for extracting an SP (Scattered Pilot) signal from the fast Fourier transformed signal; a circuit for adding a positive or negative sign to the extracted SP signal; a memory for temporarily storing the signed SP signal and an information transmission signal; a carrier interpolation circuit for performing time axis interpolation and frequency axis interpolation on the signed SP signal by a plurality of methods; a complex division circuit for performing a complex division of the information transmission signal by interpolated data; and a memory interface for detecting a timing a prescribed number of signed SP signals have been obtained and an output timing of the interpolated data according to the interpolation method.

Abstract: Circuits and methods for providing zero-gap playback of consecutive data streams in portable electronic devices, such as media players, are described. In some embodiments, a circuit includes a decoder circuit configured to receive encoded audio data and to output decoded audio data including data streams associated with a data file and a subsequent data file. Moreover, a predictive circuit, which is electrically coupled to the decoder circuit, is configured to selectively generate additional samples based on samples in the data file, where the additional samples correspond to times after the end of a data stream associated with the data file. Additionally, a filter circuit, which is electrically coupled to the decoder circuit and selectively electrically coupled to the predictive circuit, is configured to selectively combine or blend samples at a beginning of the subsequent data file with the additional samples. Note that the circuit may be included in an integrated circuit.

Abstract: A multipurpose arithmetic functional unit selectively performs planar attribute interpolation, unary function approximation, double-precision arithmetic, and/or arbitrary filtering functions such as texture filtering, bilinear filtering, or anisotropic filtering by iterating through a multi-step multiplication operation with partial products (partial results) accumulated in an accumulation register. Shared multiplier and adder circuits are advantageously used to implement the product and sum operations for unary function approximation and planar interpolation; the same multipliers and adders are also leveraged to implement double-precision multiplication and addition.

Abstract: Improved interpolator and decimator apparatus and methods, including the addition of an elastic storage element in the signal path. In one exemplary embodiment, the elastic element comprises a FIFO which advantageously allows short term variation in sample clocks to be absorbed, and also provides a feedback mechanism for controlling a delta-sigma modulated modulo-N counter based sample clock generator. The elastic element combined with a delta-sigma modulator and counter creates a noise-shaped frequency lock loop without additional components, resulting in a much simplified interpolator and decimator.

Abstract: An interpolation process for scaling is performed directly on raw data from an image pickup apparatus. Raw data, constituted by inputted Bayer pattern array are as a set of pixels positioned on respective lattice points on a square lattice. A position of an interpolation point Q is designated by an upper address that indicates a lattice point near the upper left and a lower address that indicates a position inside a lattice frame, a specific color is designated for which a pixel value is to be determined. An interpolation reference frame is determined, formed of a smallest square, which contains the interpolation point Q and with which the four vertices are formed by lattice points of the designated color, and an interpolation origin, constituted by the upper left lattice point of the interpolation reference frame, interpolation proportions d* and e* are determined. An interpolation calculation is performed.

Abstract: Methods (500, 800) and corresponding systems (100, 200, 300, 400, 900) for generating a pilot symbol (330) include providing an M-point parallel transform sequence that is a discrete Fourier transform of a CAZAC sequence (312, 504-508). The M-point parallel transform sequence (312) is distributed (316, 510) to a set of M subcarriers among N subcarriers to form an N-point frequency-domain sequence (318) wherein the M subcarriers are evenly spaced apart. An N-point inverse fast Fourier transform (320, 512) is performed to convert the N-point frequency-domain sequence to an N-point time-domain sequence (322). The N-point time-domain sequence is converted (324, 514) to a serial sequence (326), and a cyclic prefix is added (328, 516) to the serial sequence to form a pilot symbol (330).

Abstract: Data rate conversion devices and methods are provided. A method for converting a first digital signal having a first sampling rate into a second digital signal having a sampling rate close to a predetermined second sampling rate comprises the following operations: when the ratio of the first sampling rate to the second sampling rate is a repeating infinite decimal, calculate at least two calibrating coefficient values and output the calibrating coefficient values according to a predetermined rule; conduct overflow operation on the output calibrating coefficient; and interpolate the first digital signal using the output calibrating coefficient and the result of the overflow operation to obtain the second digital signal such that during any period of a certain length along time axis, sampling times of the second digital signal equals to sampling times of the second sampling rate.

Abstract: Interpolators for quadratic approximation for sinusoids are described. A sample source providing first order derivatives of sub-sampled sets of phase factor samples is used. A differentiator is coupled to receive the first order derivatives and configured to provide second order derivatives of the first order derivatives. A first scaling device is coupled to receive each of the first order derivatives. A second differentiator is coupled to receive each of the first order derivatives and configured to respectively provide second order derivatives of the first order derivatives. A second scaling device is coupled to receive the second order derivatives. A first integrator is coupled to receive output from the first scaling device for preloading, and to receive output from the second scaling device for integration. A third scaling device is coupled to receive output from the first integrator. A second integrator is coupled to receive output from the third scaling device.

Abstract: An audio data processing device and method includes selecting one multiple-S-curves, and running an interpolation arithmetic upon original points according to the selected multiple-S-curve. Selecting one multiple-S-curve includes selecting one of a plurality of S-curves corresponding to a current utilization ratio of a processor, obtaining audio data having a fixed length including sampling frequencies and the original points of the obtained audio data, and selecting the one multiple-S-curves corresponding to the selected S-curve and the obtained sampling frequencies.

Abstract: A causal impulse response function is calculated from a truncated spectrum by extending the real part of the spectrum beyond the truncation frequency and computing the imaginary part with the Hilbert transform to enforce causality. The out of band extrapolation is optimized to reduce the discrepancy between the computed and the original imaginary part in the in band frequency range so that the causal impulse response accurately represents the original spectrum. The technique can be applied to spectral with the delay phase subtracted to enforce delay causality. The Hilbert transform may be employed to maintain causality in S-parameter passivity violation correction. At frequencies where violation happens, the S-parameter matrix is scaled down by the inverse of the magnitude of the largest eigenvalue. Magnitudes at other frequencies are unchanged. An additional phase calculated by the magnitude phase Hilbert transform is added to the scaled spectrum to maintain the causality.

Abstract: The n-tap filtering for generating interpolated pixels is converted into calculation of terms consisting of the difference and sum of the pixel values of adjoining pixels. When the difference is equal to or less than a predetermined value, the calculation related to the terms including the difference is omitted, thereby reducing the calculation amount in generating the interpolated pixels. In loop processing according to a flow chart of the pixel interpolating method, the reference pixels are accessed by one pixel per one loop processing for reading pixel values thereof, and the difference and sum of the pixel values are calculate using the adjoining pixel value already read one loop before, thereby interpolating the pixel values of consecutive pixels to be interpolated. Consequently, redundant reading of pixel values is avoided, with further beneficial effects on speedy generation of the interpolated pixels and reduction of the power consumption therein.

Abstract: A control system, a method of operating the same, and a method for setting up the same are disclosed for simplified driving of a function unit parametrized by a plurality of input variables. The control system includes a setting unit and a control unit, the setting unit being used to set a number of prescribed control parameters and to feed them to the control unit. A value tuple that is fed to the function unit for the parametrization thereof is determined by the control unit as a function of the controlled variables in accordance with a stored interpolation function based on interpolation points.

Abstract: An apparatus, system, and method are disclosed for interpolating data. A cluster module locates a plurality of variable granularity data clusters within a source data set using a center selection/clustering algorithm. A conversion selection module selects a conversion function for converting each data cluster. A norm selection module selects a norm function for each data cluster. An interpolation module converts each data cluster. In one embodiment, a cross validation module iteratively cross validates and optimizes the data conversions.

Abstract: Methods for modeling a random variable with spatially inhomogenous statistical correlation versus distance, standard deviation, and mean by spatial interpolation with statistical corrections. The method includes assigning statistically independent random variable to a set of seed points in a coordinate frame and defining a plurality of test points at respective spatial locations in the coordinate frame. A equation for a random variable is determined for each of the test points by spatial interpolation from one or more of the random variable assigned to the seed points. The method further includes adjusting the equation of the random variable at each of the test point with respective correction factor equations.

Abstract: Systems and methods for converting a data stream from a first sample rate to a second sample rate using a sample rate converter that employs selectable filters. In one embodiment, the filters are implemented by providing multiple sets of filter coefficients in a memory, selecting one of the sets of filter coefficients and performing coefficient interpolation to produce filter coefficients that are convolved with the input data stream to produce a re-sampled output data stream. The input signal can be an audio signal that is convolved with interpolated polyphase filter coefficients in the sample rate converter of a digital PWM audio amplifier. The set of filter coefficients can be selected by a value stored in a filter selection register that is modifiable by a DSP or by user input. The sets of filter coefficients can be stored in a single memory and interpolated according to a cubic spline interpolation algorithm.

Abstract: Interpolation of signed values A and B is efficiently performed by simple circuitry. To calculate an interpolated value C based on a 4-bit values A (bits a3a2a1a0) and B (bits b3b2b1b0) expressing a negative number by twos complement notation and a 4-bit interpolation rate D (bits d3d2d1d0) consisting of only a decimal part, a basic expression of C=(1?D)*A+D*B is transformed into an expression composed of an unsigned part that includes a sum of products with a bit di or a logically inverted value ei of the bit di (i=0, 1, 2, and 3), and indicates an absolute value of the interpolated value C, and a signed part indicating a sign of the interpolated value C. Then, 7 bits of bits c6 through c0 are generated from an arithmetic operation of the unsigned part, and logic judgement of the signed part is performed by considering a carry from the digit of the bit c6 of the arithmetic operation of the unsigned part to generate a bit c7.

Abstract: In processing for normalizing a P-bit input digital signal, which is expressed by binary notation, to 2M?1 (0<M?P) tones, upper M bits of the input digital signal are repetitively concatenated until P bits are reached, a concatenated signal obtained as a result of concatenation is compared with the input digital signal, and a value indicated by the upper M bits or a value obtained by subtracting 1 from the value indicated by the upper M bits is determined as a normalized value depending on the comparison result.

Abstract: A technique that can contribute to improvement of processing efficiency in performing image processing employing an SIMD command is provided.

Abstract: The purpose of this invention is that the optimum approximation formula can be derived even if an analysis filter has non-linear characteristic in a discrete signal approximation system. The norm of source signal 1 is bounded. Analysis filters 2 of FIR filters yield the output signal that is expressed with polynomial of transformed source signal 1 through a unit filter. An interpolation function is calculated according to the filter characteristic based upon the multi-dimensional function transformed from the polynomial. The output signal of the analysis filter 2 is sampled after each constant interval to obtain a discrete signal. The approximation function of the power function of the source signal 1 is calculated with linear combination of the interpolation functions using the discrete signals as coefficients. The radical of this approximation function is calculated to derive the root approximation function of the source signal 1.

Abstract: A system for efficiently implementing a multi-dimensional interpolation in a way which is predicated on dynamic interpolation-input makeup, the method comprising: processing, said interpolation's first interpolation-input and said interpolation's second interpolation-input, prior to processing said interpolation's third interpolation-input, processing said interpolation's third interpolation-input as a recursion.

Abstract: A method and an apparatus for adjusting a display parameter are provided. The method includes the steps of: (a) calculating a scene change value between a current frame and a previous frame; (b) setting a first weight according to the scene change value; (c) calculating an original parameter of the current frame; (d) providing a display parameter of the previous frame; (e) calculating a display parameter of the current frame according to the first weight, the original parameter, and the display parameter of the previous frame.

Abstract: A method for a rate increase and a method for a rate reduction of a sampling input sequence into a sampling output sequence is provided. The sampling input sequence is subjected to signal processing. Signal processing maps a spreading with a first factor and an interpolation and a decimation with a second factor to generate the sampling output sequence with use of a counter. The counter and the signal processing are clocked with the higher rate, in each case, of the sampling input sequence or the sampling output sequence, respectively.

Abstract: A method and apparatus are disclosed for generating phase controlled data, based on a roaming tap interpolator. The present invention recognizes that roaming tap interpolators have inherent nonlinearities and discontinuities at the boundaries of each interpolation region. A roaming tap interpolator is disclosed that shifts the interpolation curve in time in order to avoid the undesired artifacts in the interpolation curve. A roaming tap interpolator generally comprises a plurality of delay elements that delays a first signal to generate a plurality of interpolation regions each having an associated phase; a multiplexer to select one or more of the interpolation regions; and an interpolator to process the selected one or more of the interpolation regions to generate a second signal.

Abstract: A method and apparatus for spatio-temporal compressive sensing, which allows accurate reconstruction of missing values in any digital information represented in matrix or tensor form, is disclosed. The method of embodiments comprises three main components: (i) a method for finding sparse, low-rank approximations of the data of interest that account for spatial and temporal properties of the data, (ii) a method for finding a refined approximation that better satisfies the measurement constraints while staying close to the low-rank approximations obtained by SRMF, and (iii) a method for combining global and local interpolation. The approach of embodiments also provides methods to perform common data analysis tasks, such as tomography, prediction, and anomaly detection, in a unified fashion.

Abstract: A digital signal processor for interpolating a gain (coefficient) to be applied to a digital signal, the processor including: first memory means for storing a target gain coefficient; second memory means for storing a current gain coefficient; response determining means for determining an output gain coefficient based on the target gain coefficient and the current gain coefficient; means for storing the output gain coefficient in the second memory means in place of the current gain coefficient, to be used as the current gain coefficient in subsequent operations. In this way, a gain coefficient interpolator can be implemented using hardware rather than the previous DSP software approach.

Abstract: Interpolation of signed values A and B is efficiently performed by simple circuitry. To calculate an interpolated value C based on a 4-bit values A (bits a3a2a1a0) and B (bits b3b2b1b0) expressing a negative number by twos complement notation and a 4-bit interpolation rate D (bits d3d2d1d0) consisting of only a decimal part, a basic expression of C=(1?D)*A+D*B is transformed into an expression composed of an unsigned part that includes a sum of products with a bit di or a logically inverted value ei of the bit di (i=0, 1, 2, and 3), and indicates an absolute value of the interpolated value C, and a signed part indicating a sign of the interpolated value C. Then, 7 bits of bits c6 through c0 are generated from an arithmetic operation of the unsigned part, and logic judgement of the signed part is performed by considering a carry from the digit of the bit c6 of the arithmetic operation of the unsigned part to generate a bit c7.

Abstract: Briefly, embodiments of methods or structures for reconstruction of uniform digital signal sample values from nonuniform digital signal sample values are disclosed