721 results about "Gray code" patented technology

The present invention may be embodied in a disk drive comprising a rotating magnetic media having tracks identified by binary codewords, and in a related method. Each track codeword for a particular track within a contiguous band of tracks differs from a track codeword for an adjacent track within the contiguous band of tracks by a defined number of bits, and differs from a track codeword for a nonadjacent track within the contiguous band of tracks by at least the defined number of bits. The defined number N of bits is greater than four such that at least two bit errors may be corrected when reading a track codeword.

A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of tracks defined by a plurality of servo sectors. An estimated track ID is generated representing an estimated radial location of the head. A high order Gray code in a first servo sector is detected, and errors in the high order Gray code are corrected using the estimated track ID to generate a corrected Gray code. The corrected Gray code is decoded into a first part of a detected track ID. A low order track code is detected in the first servo sector, and the low order track code is decoded into a second part of the detected track ID. The first part of the detected track ID is combined with the second part of the detected track ID.

The present invention relates to electronically assisted drug delivery devices (100). The drug delivery device may include a Gray code type detector for sensing dosage data, wherein the detector comprises a code track consisting of a sequence of alternating markings and a plurality of detectors that are mutually spaced in a direction extending along the code track. The drug delivery device may also include a dosage selector (260) which is moved in a proximal direction upon dose setting and in a distal direction upon dose injection, where the dosage selector is latched in the end of dose position by a latching element, the latching element actuating an end of dose switch for signalling the end of dose state. The drug delivery device may also incorporate power-management arrangements which effectively minimizes power consumption for the incorporated electronic circuitry.

Digitalized video images are compressed in several steps in order to provide a system for transmitting moving video pictures via narrow band channels, such as the telephone network. The system is based on any extension of the bit-plane coding technique to video sequences and lossy conditions. The compression technique can also be advantageously used in a lossless compression system. The system involves the steps of bit plane representation and skipping the least significant bit plane(s), shifting the pixels, coding with a Gray code, the use of segmentation, and motion-estimation / motion compensation and application of a transmit / not transmit / motion compensate (TX / NT / MC) procedure, exploiting of the temporal redundancy of two corresponding bit planes via an XOR operation on two successive images, and a plane-by-plane application of an extended RLEID technique. The RLEID technique includes coding a run of like binary symbols with one word, the run including a transition between the penultimate and ultimate binary symbol.

A disk drive is disclosed comprising a disk having a plurality of data tracks defined by a plurality of servo sectors, wherein each servo sector comprises a Gray coded address representing at least part of a track address. The disk drive further comprises a head actuated over the disk for detecting a first Gray coded address in a first servo sector. A second Gray coded address is generated in response to the first Gray coded address. The first Gray coded address is decoded into a first binary address, and the second Gray coded address is decoded into a second binary address. One of the first and second binary addresses closest to a target address is selected, and the head is positioned in response to the selected binary address.

A disk drive is disclosed comprising a head actuated over a disk, the disk comprising a plurality of servo tracks defined by a plurality of servo sectors. An estimated radial location of the head is generated in response to an actuator control signal. A Gray coded track ID is detected from reading a servo sector, and decoded into a detected track ID. A burst position error signal (PES) is generated from reading servo bursts in the servo sector, wherein the burst PES represents a detected fractional servo track offset of the head. When the detected track ID is corrupt, a corrected track ID is generated using the estimated radial location and the burst PES, and the actuator control signal is adjusted in response to the corrected track ID and the burst PES.

A method of forming at least one three dimensional (3D) color image of at least one object in a target space. The method comprises projecting, each of a plurality of projection cycles, a sequence comprising a plurality of gray coded light patterns, each colored in one of red green or blue, on a target space, capturing a plurality of two dimensional (2D) images of the target space during a plurality of acquisition cycles, each the acquisition cycle being timed to correspond with the projection of at least a sub sequence of the sequence, the sub sequence comprising red, green, and blue gray coded light patterns of the plurality of gray coded light patterns, extracting range data and color texture information of at least one object in the target space from the plurality of 2D images, and forming a 3D color image of the range data and color texture information.

A method and apparatus is provided for high speed, non-contact method of measuring the 3-D coordinates of a dense grid of points on a surface, including high accuracy interpolation between grid points. A plurality of pulsed laser sub-projectors sequentially illuminates a plurality of discrete Gray code bar pattern transparencies carried on a spinning circular code disk to project high frame rate structured light. The structured light is reflected by the surface and recorded at high signal-to-noise ratio by a plurality of high frame rate digital cameras, then decoded and interpolated by electronic signal processing. A numerical formula is derived for numbers of equally spaced discrete code patterns on the code disk that allow each camera to receive pulses from all sub-projectors and all patterns at a constant frame rate. Methods to derive an extended complementary Gray code pattern sequence and to normalize measured signal amplitudes are presented.

A dynamic threshold detector for a servo writer / detector in a magnetic storage system with a magnetic medium comprises a detector that receives data from the magnetic medium and that selects one of a first condition and a second condition based on at least one of an amplitude, a sign and bit transitions of the data. A threshold selector selects a first set of thresholds when the first condition is selected by the detector and a second set of thresholds when the second condition is selected by the detector. The data includes pairs of numbers with a first number and a a second number each having one of a positive sign and a negative sign and wherein the detector selects the first condition when the signs of the pairs are the same and the second condition when the signs of the pairs are different.

An ultrasound imaging method for forming an image of an object using received signals reflected from the object, received after transmitting an ultrasound pulse to the object. The inventive method comprises the steps of (a) transmitting a first set of the ultrasound pulses to the object by applying voltages according to a first code of a pair of modified Golay codes to one or more transducers; (b) performing pulse compression on a first set of reflected signals of the first set of the ultrasound pulses reflected from the object; (c) transmitting a second set of the ultrasound pulses to the object by applying the voltages according to a second code of the pair of the modified Golay codes to said one or more transducers; (d) performing pulse compression on a second set of reflected signals of the second set of the ultrasound pulses reflected from the object; (e) adding the pulse compressed signals of the first and the second sets of the reflected signals; (f) producing a receive-focused signal by using the added signal; and (g) displaying the image according to the receive-focused signal after signal processing.

A matched filter is configured for matching an input signal to a plurality of programmable-length complementary Golay-code pairs. The matched filter includes a sequence of delay elements configured for delaying the input signal with respect to at least one delay vector. A sequence of programmable seed vector insertion elements is configured for multiplying the input signal and delayed versions of the input signal by a set of seed-vector values. At least one of the seed-vector values may be set to zero to facilitate processing Golay codes having different lengths.

A method of transmitting digital information comprises the steps of forward error correction encoding a plurality of bits of digital information using complementary pattern-mapped convolutional codes, modulating a plurality of carrier signals with the forward error corrected bits, and transmitting the carrier signals. The modulation can include the step of independently amplitude shift keying in-phase and quadrature components of the QAM constellation using Gray code constellation points corresponding to amplitude levels. Transmitters that transmit signals in accordance with the method and receivers that receive such signals are also included.

A hierarchical QAM system allows the transmission of different sources by embedding the relative constellation points. At the transmitter the constellations generated by the different sources are remapped by a grey coder and then combined. At the receiver, the different source data are decoded by using a corresponding grey code demapper.

The invention relates to a rapid three-dimensional measurement method based on colorful grating projection in a three-dimensional scanning system. The method comprises the following steps: selecting four pure colors of green, yellow, cyan and white so as to carry out color strip encoding, wherein the G component values of the four pure colors are 255, and the R component values and the B component values of the four pure colors are respectively 0 or 255; after finishing color encoding, carrying out sinusoidal modulation on the G component of strip color to finally obtain a projective grating; on one hand, resolving G component information to obtain a folding phase value by a method based on Fourier transform, on the other hand, carrying out binaryzation on the R component and B component of an image by an iteration threshold method in the color image segmentation link, and automatically assigning 255 to the G component; and segmenting an image decipher to obtain phase period information so as to unfold the phase. By utilizing the method, inconvenience for cutting brought by periodic occurrence of light and shade strip-shaped areas in the image caused by G component sinusoidal modulation can be well avoided, and a train of thought for realizing three-dimensional dynamic measurement can be provided on the premise of not influencing the measurement accuracy.

The invention discloses a method for three-dimensionally reestablishing a surface contour of a human body, and the method is characterized by comprising the following steps: (1) the projection region of a protector, the shooting region of a camera and the measured part of the human body are corresponding; (2) the projector projects one image once, the camera collects one image, and the projected image comprises black and white images, Gray code images and phase shift grating images; and (3) the collected pictures are processed to obtain the three-dimensional information of the surface contour of the human body. In the invention, a phase error compensation curve is designed and the reestablishment accuracy of the surface contour of the human body is enhanced according to the characteristics of the projector and the time characteristics in the projecting and shooting courses; a common period calibration method is improved and used for calibrating the absolute phase of the surface contour of the human body, thereby enhancing the reestablishment accuracy of the surface contour of the human body; and an independent projected image generating module is adopted and used for generating the projected images and controlling the projected images of the projector, thereby facilitating the control on the time interval between the projected images of the projector and the collected images of the camera and enhancing the stability of phase error fitted functions.

A method of snap-shot data training to determine the optimum timing of the DQS enable signal in a single read operation is provided. This is accomplished by first writing a Gray code count sequence into the memory and then reading it back in a single burst. The controller samples the read burst at a fixed interval from the time the command was issued to determine the loop-around delay. A simple truth table lookup determines the optimum DQS enable timing for normal reads. Advantageously, during normal read operations, the first positive edge of the enabled DQS signal is used to sample a counter that is enabled every time a command is issued. If the counter sample changes, indicating timing drift has occurred, the DQS enable signal can be adjusted to compensate for the drift and maintain a position centered in the DQS preamble. This technique can also be applied to a system that uses the iterative approach to determining DQS enable timing on power up. Another embodiment of the invention is a simple, low latency clock domain crossing circuit based on the DQS latched sample of the counter.

The invention discloses a high-adaptability three-dimensional measuring method based on color structured light in a three-dimensional scanning system. The method comprises the following steps of: coding according to the Gray coding principle by use of 6 pure colors; performing sinusoidal modulation of three components R, G and B at the same time to obtain a color grating for projection; designing an auxiliary grating according to the color grating; projecting the designed color grating and auxiliary grating to a measured object; performing superposition operation of the collected two grating deformation diagrams to obtain the reflectivity of each pixel; compensating the grating deformation diagrams according to the reflectivity of each pixel; performing color image division of the compensated grating deformation diagrams; decoding the divided image to obtain corresponding phase period information; graying the compensated grating deformation diagrams and obtaining the wrapped phase value of each pixel by Fourier transform; realizing phase unwrapping according to the decoded phase period information of each pixel; and finally, realizing three-dimensional reconstruction according to the corresponding relationship between the phase and the object height information.

Methods, apparatus and systems for multilevel data communication comprises dividing a set of information bits to be transmitted into a first group and a second group; encoding the first group to generate a block code, selecting a subset of symbols in a constellation of symbols in dependence on the block code according to a Gray-coded mapping function, selecting a symbol within the subset in dependence on the second group according to a Gray-coded mapping function, and transmitting the selected symbol.

The invention discloses a color structured light three-dimensional measuring method, apparatus and device, and a storage medium. The method comprises the following steps of coding four color stripe patterns by adopting a sinusoidal phase shift coding method, a segmented step phase coding method and Gray codes; sequentially focusing and projecting the four color stripe patterns on a reference planeand a measured object through a DLP projector; acquiring the stripe patterns which are not modulated on the reference plane and after height modulation deformation of the measured object through a color CCD camera; performing decoding processing on the two groups of the stripe patterns to obtain a continuous phase difference value of the measured object; and solving three-dimensional height information of the surface of the measured object by utilizing a triangular method. Through the measuring method based on color composite coding which fuses sinusoidal phase shift coding, segmented step phase coding and the gray codes, the three-dimensional measurement can be realized by only four color patterns by means of a triangular principle; and therefore, the method is small in projection amount, high in processing speed and good in anti-jamming capability, and is suitable for fast and high-precision three-dimensional measurement of objects with the non-continuous surfaces in a static scene.

A first Gray code technique and a second raster calibration technique can be combined to create a precise mapping between pixel locations of the camera and pixel locations of the projector(s). In one aspect the technique of using the raster calibration images is eliminated by interpolating the projector coordinate information decoded from the Gray code images. In another aspect camera images are processed to reduce errors caused by noise so that text can be displayed without any noticeable misalignment between projectors. In a third aspect, a scale factor is calculated based on the relative height / width of projector regions in the captured calibration images. Calibration images are recalculated using the scale factor to provide greater correspondence between the mapping of a low resolution camera to the high-resolution projectors.

The invention relates to a system calibration method for grating stripe projection-based three-dimensional measurement. A calibration object is a system consisting of a projector and a video camera. The method is implemented by the following steps: (1) adjusting the relative positions of the projector and the video camera, so that the projector is parallel with a lens longitudinal axis of the video camera; (2) calculating the absolute phase position of a reference plane by combining a sinusoidal grating phase-shifting algorithm and a Gray code; (3) placing at least two standard blocks, of which the heights are known and different, on the reference plane and calculating the absolute phase position distribution; (4) calibrating a three-dimensional measuring system: establishing projection and imaging models, deducing an object point height-phase position relational expression of an object to be measured, and fitting the coefficients of the height-phase position relational expression by utilizing the standard blocks with known heights and the absolute phase position distribution thereof and through a least square method; (5) calculating the absolute phase position value of the object to be measured and obtaining the height distribution from a calibrated expression so as to realize height measurement of the object. The method has the advantages of high operability and high measuring precision.

The related phase expand method based on Gray code in 3D scanning system comprises: according to space binary coding requirements, designing seven gradual-dimidiating projection grating graphs and four grating 90deg phase shift graphs; projecting to the target, using CCD to take photo back to a computer; obtaining the folding-phase graph between -pi ~ pi; cutting the projection graph as threshold, Gray coding, and dividing accurate period to expand the folding-phase graph and obtain the only phase value; finally, to the failed area, traverse comparing and compensating phase for expand.

The invention discloses a ternary content addressable memory (TCAM)-based range matching device and a TCAM-based range matching method, and belongs to internet high-speed message classification techniques. The device mainly comprises a TCAM memory cell, a logical judgment unit and an action unit. The method comprises the following steps of: A, performing prefix expansion or Gray code expansion on rule conditions in a classification rule base, and then compressing and depositing the rule conditions in the TCAM according to priority, namely depositing two expanded rules in a TCAM list item; and B, extracting a search keyword from the head part of a message, matching the search keyword with the TCAM to obtain a matching result index, and executing correlative actions according to correlative rules. Aiming at the problem of list item expansion during the range matching of high-speed message classification, by means of the device and the method, the space requirement of the TCAM is reduced and the power consumption of the TCAM is reduced at the same time.

A method (100) for simplifying soft-decision metric decisions in a M-ary modulation system includes determining (102) a single function for a soft-decision metric for each bit in a symbol by restricting the set of all possible Gray-coded constellation points to those closest to a boundary between a bit value of 0 and 1 for each bit in the input symbol and applying a predetermined function corresponding to the range of restricted constellation points to the entire possible range of symbols. A next step includes inputting (104) a symbol having real part, x, and an imaginary part, y. A next step includes (106) setting a soft-decision metric for each bit in the symbol using the predetermined function from the determining step (102).

An anti-phase noise amplitude phase combined keying modulation and demodulation method belongs to the technical field of modulation and demodulation, the method is characterized in that, a circular constellation diagram construction method and a circular constellation diagram selection method are firstly utilized for designing a constellation diagram structure with good symbol error performance; secondly, a bit mapping algorithm which is proposed by the invention is utilized for solving the difficulty of carrying out the Gray-code mapping of other constellation diagrams except the quadrature amplitude modulation (QAM), thereby ensuring the bit error performance of the proposal; the demodulation proposal with high reliability and low complexity is further matched for use, the actual bit error performance is not only far better than the QAM which uses the Gray codes under the phase noise, but also has no obvious loss compared with the Gray-code QAM when in only consideration of Gaussian white noise; finally, the design method which is proposed by the invention is simple and easy to operate, thereby being easily expanding to any order, facilitating the application in a communication system with serious phase noise of global digital broadcasting and the like and possibly reducing the costs and the complexity of a receiver at the same time of ensuring the symbol error performance of the system.

The outer convolutional coding of the signals used to transmit mobile-handheld (M / H) service data within digital-television (DTV) signals is subjected to anti-Gray coding, either before or after its interleaving, but before its inner convolutional coding. In a receiver for such M / H-service data, portions of the trellis decoded DTV signal containing soft decisions concerning symbol-interleaved convolutionally coded M / H-service data are recoded for a Gray-code mapping of symbols to modulation levels. This is done either before or after symbol de-interleaving, but before decoding the outer convolutional coding. Soft decisions concerning extrinsic information to be fed back to the ⅔ trellis decoder to close a turbo decoding loop are derived from soft decisions as to the M / H-service data, which derivation includes re-coding for a binary-code mapping of symbols to modulation levels. Each re-coding procedure can be performed using ROM, but preferably is performed using simple digital logic.

A thermometer code to sign and magnitude converter that is particularly useful in a flash ADC is provided. This comprises two conversion units. The first is a thermometer code to Gray code converter and the second a Gray code to sign and magnitude converter. Preferably, the Gray code is of a kind that has a sign bit and has the other bits symmetrically disposed about zero. This form is easily converted to a sign and magnitude code, which is advantageous as it reduces the latency of the converter, which is particularly useful at high data rates.

Methods, systems, and apparatuses for updating pointers in memory are described. A device can include pointer logic and a memory that stores a memory pointer. The pointer logic can increment or decrement the memory pointer according to Gray code. The device can increment or decrement the memory pointer in response to a pointer change command and can be configured to first verify a password associated with the command. The device can send an acknowledgement that the command has been received and / or executed. Multiple increments or decrements of the memory pointer can occur in response to a pointer change command configured as a single multiple-increment-or-decrement command or as multiple single-increment-or-decrement change commands. The device can determine an updated value for each of a first memory pointer portion and a second memory pointer portion of the memory pointer.