130 results about "Gray code" patented technology

The invention discloses a fringe projection three-dimensional shape measurement method based on frequency domain and time domain joint coding, and the method comprises the following steps: firstly, embedding a multi-frequency three-step phase shift fringe pattern in the vertical direction based on multi-scale region division, introducing four-step phase shift and complementary Gray code joint coding in the horizontal direction, generating a coding pattern set, and carrying out the projection; after an image is collected, frequency domain transformation and time domain decoding are carried out respectively, and a vertical dominant frequency position, a horizontal period number and a wrapped phase are obtained; then, combining a main frequency position in the vertical direction with a period number and a wrapped phase in the horizontal direction, and extracting a space coordinate of a direct illumination component based on frequency position invariance; and finally, establishing a pixel homonymy point mapping relation between the projector and the camera, and realizing high-precision three-dimensional reconstruction. Compared with a traditional frequency shift method, the method has the advantages that projection patterns are greatly reduced, reconstruction precision and anti-interference performance are improved, and the method is suitable for dynamic three-dimensional measurement under complex illumination conditions such as specular reflection, semitransparent shielding and subsurface scattering.

The invention discloses a semantic segmentation method based on phase contour constraint, and belongs to the technical field of computer vision. The method comprises the following steps of: acquiring a two-dimensional texture image and a deformed stripe image of a scene to be detected in the same view field by using a calibrated camera-projector system; resolving the deformed fringe image through a multi-step phase shift and Gray code technology to obtain absolute phase distribution, and calculating a gradient field; according to a preset sudden change condition, extracting a physical edge contour reflecting the depth change of the object from the gradient field; and mapping the physical edge contour into the two-dimensional texture image based on a pixel coordinate corresponding relation to accurately define a semantic object region, endowing a corresponding category label, and finally generating a semantic label mask image. According to the method, the uncertainty of the visual texture edge is corrected by utilizing the physical phase information, the problem of edge extraction in a complex illumination scene is effectively solved, automatic generation of semantic segmentation data is realized, and the training precision and robustness of a semantic segmentation model are improved.

The invention discloses an optical Gray code encoder temperature compensation method and system based on an NTC resistance network, and the method comprises the steps: calibrating a PD signal drift law in a working temperature range, designing an NTC voltage division circuit matched with the law, and integrating the NTC voltage division circuit to a comparator, thereby achieving the real-time offset of the PD signal temperature drift. According to the scheme, the defects that in the prior art, complexity is high and cost is high are overcome, compensation precision within + / -0.5% is achieved only through basic electronic elements, the response speed reaches the microsecond level, cost is reduced by 60% or above, the method is suitable for wide-temperature-range scenes ranging from-40 DEG C to 85 DEG C, and a low-cost and high-precision temperature compensation solution is provided for precise measurement of high-end equipment.

The invention relates to a fringe projection high-reflection surface phase unwrapping method based on frequency reuse. The fringe projection high-reflection surface phase unwrapping method comprises the steps of collecting a multi-frequency fringe image and dividing the multi-frequency fringe image into an overexposure area and a non-overexposure area, solving a wrapped phase in the non-overexposure area by adopting a generalized phase shift method, obtaining an initial unwrapping phase based on a multi-frequency heterodyne algorithm, and performing block filtering and interpolation processing to obtain a fringe projection high-reflection surface phase unwrapping phase. A continuous unwrapped phase containing a high-reflection area is obtained, a complementary Gray code consistent with a wrapped phase period is constructed in combination with a multi-threshold constraint and is used for correcting the stripe level of an overexposure area, brightness attenuation design is further carried out on low and medium frequency stripes, frequency reuse is achieved, and the high-reflection area is obtained. Obtaining an unwrapped phase of an overexposure point in a non-high-frequency stripe and mapping the unwrapped phase to a high frequency; the method comprises the following steps of: extracting and fusing a wrapped phase by adopting one-dimensional Fourier and Hilbert transform for areas with overexposure of each frequency, and selecting and inhibiting spectrum leakage through a complete period, so that effective correction of the wrapped phase and stripe level of an overexposure point is realized, and a reliable unwrapped phase is obtained.

The invention relates to the technical field of fringe projection three-dimensional reconstruction, in particular to a point cloud enhancement method and system based on polarization structure perception and trend guided recovery. The method comprises the following steps: acquiring a multi-angle polarization image, and generating an object area mask based on a polarization angle consistency mask, a polarization angle gradient mask and a linear polarization degree mask; obtaining an original phase diagram through four-step phase shift and complementary Gray codes, obtaining a missing region in an object according to hole distribution of the original phase diagram, and adding morphological structure indexes and local variance features to recognize a real self-shadow region; aiming at the identified real self-shadow area, establishing a structure guiding recovery model combining a first-order structure gradient guiding item and a second-order structure gradient guiding item to obtain a complete object point cloud; and separating a background and an invalid shadow in the object point cloud through the object area mask to obtain a point cloud which only retains the object area.

The invention provides an edge side industrial data lightweight preprocessing caching method, and belongs to the technical field of industrial data. According to the method, the data acquisition quality is improved through Gray code anti-interference coding, dynamic sampling is realized through adaptive sampling rate adjustment and weak abnormal feature weight vectors, a fault position is accurately positioned through wavelet decomposition and a high-frequency fault feature sparse matrix, a semantic perception compression encoder is matched with a dispersion evaluation matrix to carry out differential coding, and the accuracy and the reliability of the algorithm are improved. According to the overall systematic technical scheme, the transmission path is optimized through a network transmission graph model, and all links from signal acquisition, self-adaptive processing, intelligent compression, dynamic cache management to network optimization are optimized. The technical problems that the cache occupancy rate is too high and the data transmission delay is large due to the fact that the multi-source signals of the industrial equipment are difficult to pre-process efficiently on the edge side are solved.

The application discloses a physical layer key generation method and system based on Gray-CDF quantization and adaptive LDPC syndrome negotiation. The legal communication parties acquire channel characteristic sequences in reciprocal wireless channels, determine multi-level equal probability quantization thresholds according to empirical cumulative distribution functions of local channel characteristics, and adopt Gray codes to map adjacent quantization intervals into code words with only one different bit, so as to generate original key sequences; subsequently, LDPC syndrome lengths are adaptively determined according to current channel quality or initial bit inconsistency rate estimation values, the syndromes are disclosed through a public channel to complete key error correction, and retry or discard processing is performed on decoding failure frames; after successful negotiation, privacy amplification is performed according to disclosed leakage, and a consistent key is obtained. The application can improve original key generation rate, reduce negotiation disclosure, and improve the reliability of physical layer key generation and the available key rate.

The invention provides a metal part surface defect detection method and device, electronic equipment and a storage medium, the defect detection method comprises the following steps: projecting a Gray code pattern and a sine stripe pattern to a to-be-detected surface of a metal part, and using a 3D camera to shoot a to-be-detected image containing the to-be-detected surface; obtaining an enhanced gradient magnitude image based on the to-be-detected image, and obtaining an enhanced absolute phase image based on the to-be-detected image; and splicing the enhanced gradient magnitude image and the enhanced absolute phase image to obtain a dual-channel image, inputting the dual-channel image into a trained CNN model, and obtaining a defect type output by the CNN model. The defect detection method can detect the defects on the surface of the metal piece.

The application discloses a phase solving method based on sequence pixel extreme value positioning, relates to the fields of computer vision and optical measurement, and comprises the following steps: designing M line shift or phase shift fringe patterns and N complementary gray code patterns, projecting the patterns to an object to be measured in sequence, collecting images of the object to be measured under different fringe patterns, and obtaining M line shift fringe images or phase shift fringe images and N complementary gray code images; performing phase calculation on the collected M line shift fringe images or phase shift fringe images, and obtaining a wrapped phase image; decoding the collected first N-1 gray codes to obtain K1 orders, and decoding all the N gray codes to obtain K2 orders; combining the wrapped phase image and the multiple gray code projection images to perform phase unwrapping, and obtaining a phase unwrapping image; and through the innovative extreme value positioning and adaptive exposure processing mechanism, the accuracy, the robustness and the reliability of the phase solving are effectively improved, and the problem that the measurement effect of the prior art is poor in a complex environment is solved.

The invention provides a plano-convex lens curvature radius detection method and system based on structured light reconstruction and sub-pixel fitting and a medium, and the method comprises the steps: collecting a multi-angle calibration plate image based on a camera, and calibrating camera parameters; acquiring a coded image based on the projector, and calibrating parameters of the projector; projecting a Gray code pattern based on the calibrated projector, and acquiring a coding graph sequence based on the calibrated camera to obtain three-dimensional point cloud data; analyzing the three-dimensional point cloud data based on an edge detection operator, extracting edge features of the convex surface region, and performing sub-pixel fitting on the edge features of the convex surface region based on a curved surface interpolation algorithm to obtain plano-convex lens contour information; the method comprises the following steps: constructing a spherical surface model, fitting the spherical surface model according to a least square method, calculating a curvature radius result of a convex surface area based on the optimized spherical surface model, realizing non-contact detection through cooperation of a camera and a projector, avoiding pollution or damage of an optical surface, and improving detection precision and efficiency.

The utility model discloses a bridge rotation angle automatic measurement coding ruler which comprises a coding ruler body, a rotation angle scale area arranged above the coding ruler, a Gray code area arranged below the coding ruler and a photoelectric reading instrument. The coded ruler body is made of stainless steel strips. The coding ruler body is suspended on a bridge turntable, and the coding ruler body is driven to rotate synchronously when a bridge rotates horizontally; the photoelectric reading instrument is U-shaped and is fixedly arranged on a bridge bearing platform; when the coded ruler body rotates, the coded ruler body and the photoelectric reading instrument generate relative displacement; the Gray code area below the coding ruler body is embedded into a U-shaped opening of the photoelectric reading instrument, the photoelectric reading instrument recognizes the Gray code, and the rotation angle of the bridge is determined according to the Gray code. According to the utility model, the measurement efficiency can be obviously improved, automatic measurement is realized, and the measurement result precision is high.

The present disclosure relates to image signal and phase detection autofocus signal extraction and storage in an arithmetic logic unit. An arithmetic logic unit (ALU) includes a front end latch stage coupled to a signal latch stage coupled to a Gray code (GC) to binary stage. A first input of an adder stage is coupled to receive an output of the GC to binary stage. An adder input latch stage includes first and second adder input latches including first and second inputs coupled to receive the output of the GC to binary stage. An adder input multiplexer stage includes an output coupled to a second input of the adder stage and first and second inputs coupled to outputs of the first and second adder input latches, respectively.

The invention provides a spatial light modulation method and system for Gray code coding rearrangement, and relates to the technical field of computational imaging and spatial light modulation. According to the method, a Gray code sequence and a high-performance basic modulation matrix are combined, a basic modulation matrix is constructed according to a target image resolution ratio and a sampling rate, a Gray code index sequence with only one different adjacent indexes is generated, a measurement matrix is obtained by rearranging the matrix through a mapping function, and the measurement matrix is loaded to a spatial light modulator to code a light signal; and the double-path detector collects transmitted and reflected light intensity response and performs differential processing, and inputs a compressed sensing reconstruction algorithm to restore an image. According to the invention, stable and efficient information capture at a low sampling rate is realized, the anti-interference capability and repeatability of the system are improved, the hardware compatibility is strong, the implementation cost is low, and the method is suitable for the fields of single-pixel imaging, three-dimensional measurement and the like.

A gray code is controlled suitably for a range.A distance measuring device includes one or a plurality of light emitting elements, a plurality of light receiving elements, a first counter, an encoder, a decoder, a second counter, and a distance extraction circuit. The plurality of light receiving elements receives light from the one or the plurality of light emitting elements reflected on a target. The first counter is a binary code of n digits from a first value to a second value of 2n−1−(the first value), and performs, at every predetermined time, state transition of a first binary code in which a value next to the second value is set as the first value. The encoder converts the first binary code into a gray code of n digits. The decoder acquires the second binary code of n digits from the gray code based on a light reception timing of the light receiving elements. The second counter counts the number of times of light reception in the plurality of light receiving elements corresponding to each of the second binary codes. The distance extraction circuit measures a distance to the target on the basis of a discrete value acquired by the second counter.

The application discloses a double-edge triggered asynchronous Gray code counter, wherein a first stage trigger Rise1 is used as a rising edge triggered D trigger, and the rest of the stage triggers Fall1, Fall2 and Fall3 are used as falling edge triggered D triggers. The application solves the problem that the utilization of clock frequency is not maximized due to the generation of the first stage flag signal in the existing Gray code counter.

Disclosed is a decision feedback equalizer, which includes a summator that receives a gray code-based PAM-4 signal, a first bit signal, and a second bit signal, and outputs an input voltage obtained by adding a preset coefficient to a voltage level of the PAM-4 signal in response to the first bit signal and the second bit signal, and a decoder that receives the input voltage and first to third reference voltages of the PAM-4 signal and outputs the first bit signal and the second bit signal, and the decoder includes a first comparator that outputs the first bit signal by comparing a magnitude of the input voltage with a magnitude of the first reference voltage, and a second comparator that outputs the second bit signal by comparing charge-discharge intensities of the input voltage and the second and third reference voltages.

This disclosure provides a robot control method, comprising: calibrating an RGB camera to obtain a coordinate transformation matrix between the camera coordinate system and the world coordinate system; attaching Gray code coded points to each joint position of the robot, obtaining the spatial position information of the Gray code coded points through the RGB camera, thereby obtaining the robot's pose and joint position in the world coordinate system; using the camera to acquire image sequences of the human-robot collaborative environment in real time, processing the images in the image sequences to obtain human key points and semantic information of the key points; performing stereo vision matching on the semantic information to obtain human pose information; establishing a human body model based on a capsule bounding box, and calculating the minimum human-robot distance through the human body model; obtaining a human-robot safety index based on the minimum human-robot distance; and selecting a safe and compliant control strategy for the robot based on the human-robot safety index, and using the safe and compliant control strategy to control the robot.

This application relates to a two-stage Gray code counter with redundant bits. An N-bit counter includes a lower counter having a first output of M bits, the lower counter operating at a first count frequency. An upper counter having a second output of N-M+L bits operates at a second count frequency. The second count frequency is equal to the first count frequency divided by 2 (M‑L) An error correction controller is coupled to receive the first and second outputs and to perform operations including comparing L least significant bits (LSBs) of the second output to at least one most significant bit (MSB) of the first output, and correcting N-M MSBs of the second output in response to the comparison. The lower bits of the N-bit counter are the M bits of the first output, and the upper bits of the N-bit counter are the corrected N-M MSBs of the second output.

The application discloses a PCB defect detection method based on a surface structure light three-dimensional reconstruction, belongs to the field of computer vision, optical detection and automation testing, and is used for solving the problem of PCB defect detection based on surface structure light three-dimensional reconstruction, and points are that phase shift codes and complementary gray code gratings are projected to a to-be-detected PCB board to obtain light intensity images of the to-be-detected PCB board; three-dimensional point clouds and shadow area mask images are obtained according to the light intensity images; according to the shadow area mask images, two-dimensional pixel coordinates corresponding to the shadow area are converted into three-dimensional coordinate points; the interpolation fitting method is used to complete the three-dimensional point clouds in the coordinate area of the three-dimensional coordinate points; PCB component point clouds and PCB substrate plane point clouds are separated; the PCB component point clouds are matched with standard point clouds, difference points between the PCB component point clouds and the standard point clouds are calculated under a given distance threshold, and if the number of the difference points is not less than a threshold number, then the component is defective.

The application provides a three-dimensional measurement method based on four-element complementary Gray code auxiliary phase unwrapping. The method comprises the following steps: generating, projecting and shooting phase shift fringe patterns and four-element Gray code patterns; calculating wrapped phases and average intensities; dividing the wrapped phases into two regions, generating binary masks of the two regions, and obtaining a new wrapped phase by using a cut-off point translation technology; using the average intensities and their scaling values as thresholds, obtaining Gray code words, and calculating two sets of orders; correcting the two sets of orders by using a strategy based on a connected region marking algorithm; respectively unwrapping the two sets of wrapped phases and orders; combining the two unwrapped phases to obtain a final unwrapped phase; subtracting a reference plane from the final unwrapped phase, and converting phase information into height information through a phase height model. The three-dimensional measurement method based on four-element complementary Gray code auxiliary phase unwrapping provided by the application has high measurement efficiency, good robustness and high measurement result precision.

This invention discloses a method for calculating absolute phase using a generated two's complement image, comprising the following steps: generating a sinusoidal encoded image, wherein the number of sinusoidal fringes in the image is 2. n Projection is achieved using the N-step phase-shifting method, generating a total of n+1 Gray code images. The wrapping phase is calculated, and the Gray code images are decoded and normalized to obtain the normalized binarized image GB. 1、 GB2…GB n+1 In this process, the GB1 image remains unchanged, while the remaining images are XORed with the previous XOR image to segment the spatial regions of the Gray code, resulting in XOR images XG1, XG2, XG3…XG n+1 Using formula k x =XG1*2 n‑1 +XG2*2 n‑2 +…+XG n‑1 *2 1 +XG n *2 0 Calculate the series k corresponding to the phase of the package. x Using formula k y =XG1*2 n‑1 +XG2*2 n‑2 +…+XG n‑1 *2 1 +XG n *2 0 +XG n+1 Calculate the two's complement series k y The global phase is calculated by selecting 0~π / 2, π / 2~2π / 3, or 2π / 3~2π as the calculation interval within a single wrapper period. This invention can solve the 2π phase jump that exists during the phase solution process, ensuring the final imaging accuracy and imaging quality.

The application relates to a three-dimensional measurement method based on a modified Gray code pattern. The three-dimensional measurement method based on the modified Gray code pattern comprises the following steps: S1, determining the Gray code bit number n=x required by a to-be-measured object for three-dimensional measurement; S2, generating an n=x-bit conversion sequence, and converting the conversion sequence into a Gray code sequence, wherein after the Gray code sequence is characterized by black and white stripes, a to-be-projected Gray code pattern is obtained, wherein the narrowest stripe width of the to-be-projected Gray code pattern is greater than a set threshold; S3, projecting the to-be-projected Gray code pattern on the to-be-measured object through a structured light projection device; and S4, collecting a surface stripe image of the to-be-measured object, and calculating three-dimensional coordinates of the to-be-measured object according to the surface stripe image by using a triangular principle. The three-dimensional measurement method based on the modified Gray code pattern can be applied to high-speed and high-dynamic-range three-dimensional measurement, and the risk of decoding error is reduced.

The present application relates to the technical field of visual detection, and discloses a gear tooth profile defect detection method and system based on image recognition, the method comprising: carrying out pixel-level gray difference coding on a gear end face original image to obtain a gray coding sequence; based on the gray coding sequence, carrying out neighborhood comparison on the Hamming distance between pixels in the gear end face original image to obtain a local anomaly distribution; carrying out intensity sorting screening on the local anomaly distribution to obtain a candidate abnormal seed point; taking the candidate abnormal seed point as a starting point, carrying out similarity weighted region growing on the candidate abnormal seed point to obtain a suspected defect region; carrying out consistency checking on the suspected defect region, carrying out outlier elimination on the pixel coding deviation value of the checked region to obtain a refined defect region, and carrying out edge smoothing processing on the refined defect region to obtain a gear face damage region of the gear end face original image; the present application can improve the efficiency of a gear tooth profile defect detection based on image recognition.

The invention belongs to the field of magnetic encoders, and discloses an absolute value type magnetic encoder based on a nested code pattern, which is characterized in that a first layer of monorail Gray code is arranged, and a sensor of the first layer of monorail Gray code generates a seed symbol combination when a magnetic ring of the first layer of monorail Gray code rotates for a circle; the magnetic rings of the first layer of monorail Gray codes are divided into intervals by the seed symbol combination; two adjacent intervals are taken as a first-level coarse separation interval to obtain a first-level coarse separation interval, second-level coarse separation is carried out on the second-layer single-track Gray code in the first-level coarse separation interval, a sensor of the second-layer single-track Gray code generates a seed symbol combination when a magnetic ring of the second-layer single-track Gray code rotates by a circle, and the seed symbol combination is combined with the second-layer single-track Gray code; the first-level coarse separation interval is divided into two second-level coarse separation intervals through the seed symbol combination, and each second-level coarse separation interval is a degree. The absolute value type encoder is low in magnetic ring machining difficulty, insensitive to installation errors, high in angle precision and resolution ratio and easy to miniaturize.

A computer-implemented method of operating a counter is described, the method comprising: i) performing a counting operation, where the counting operation is performed in a bitwise manner, in particular using Gray codes; ii) segmenting the counting operation using wear leveling; and iii) performing an error correction scheme for the count operation using majority voting.

The application provides a spatial light modulation method and system of Gray code coding rearrangement, and relates to the technical field of computational imaging and spatial light modulation. The method combines a Gray code sequence and a high-performance basic modulation matrix, a basic modulation matrix is constructed according to a target image resolution and a sampling rate, a Gray code index sequence with only one different adjacent index is generated, a measurement matrix is obtained through a mapping function rearrangement matrix, the measurement matrix is loaded to a spatial light modulator to code light signals, a double-channel detector collects transmission and reflection light intensity responses and performs differential processing, and a compressed sensing reconstruction algorithm is input to recover an image. The application realizes stable and efficient information capture at a low sampling rate, improves the anti-interference ability and repeatability of the system, has strong hardware compatibility, low implementation cost, and is suitable for the fields of single-pixel imaging, three-dimensional measurement and the like.

The invention discloses a universal grid coding method based on multidimensional dimensions, and relates to the technical field of dimension coding. The method comprises the following steps: establishing a dimension scale grid, and discretizing a dimension to be coded through the dimension scale grid to obtain a dimension level width; based on the dimension hierarchy width, calculating to obtain a dimension coordinate vector and a hierarchy maximum bit width; based on the hierarchical maximum bit width, performing binary conversion and zero padding operation on the dimensional coordinate vector to obtain a dimensional binary hierarchical sequence; the method comprises the following steps of: calculating Shannon entropy of a dimension to be coded to obtain a dimension priority weight, and performing dislocation coding on a dimension binary hierarchical sequence by adopting a Hilbert coding method based on recursive structure judgment based on the dimension priority weight to obtain a dimension sequence code; and performing secure confusion and enhanced optimization on the dimension sequence code by adopting a gray code transformation method based on chaotic mapping to obtain a dimension optimization code, thereby realizing grid coding of the dimension to be coded.

The invention discloses a privacy protection-oriented anonymized data watermarking method and device and a medium, and relates to the field of privacy protection, and the method comprises the steps: encrypting to-be-embedded original watermark information, and generating encrypted watermark information; performing error correction coding on the encrypted watermark information to obtain a watermark coding sequence, and converting the watermark coding sequence into a Gray code sequence; sorting the data records in the original anonymized data set based on preset attributes to obtain a plurality of record groups; based on the segmentation numerical value of the Gray code sequence, determining the number of records needing to be modified in each record group; and randomly selecting the data records corresponding to the number, and modifying the selected data records to generate the anonymized data containing the watermark. By combining cryptographic encryption, error correction coding and a data modification mechanism keeping anonymization, reliable traceability of illegal distributors is realized on the premise of ensuring that the data anonymization level is not reduced, so that an effective balance mechanism is established between data sharing and privacy security.

This invention discloses a parity check circuit and data verification method for a global Gray code counter in CMOS image sensors, relating to the field of automotive-grade CMOS image sensor technology. It aims to solve the problems of existing CIS architectures being unable to cover the entire data sampling verification chain, the large area overhead of traditional parity check circuits, and verification failures caused by asynchronous sampling timing misalignment. The parity check circuit includes a Gray code data input terminal, a parity bit generator, and a storage write control terminal. The parity bit generator utilizes the conversion characteristics between Gray code and binary code to generate an even parity bit by bitwise XORing the high N-i bits of an N-bit Gray code. This parity bit is equivalent to the i-th bit of the corresponding binary code and maintains a fixed phase deviation from the Gray code. The storage write control terminal controls the data and the parity bit to be written to the storage unit according to the phase deviation. This invention achieves end-to-end data reliability verification, significantly reduces chip area, adapts to asynchronous sampling timing, and meets the functional safety requirements of automotive-grade CIS.