91results about How to "Remove random noise" patented technology

An MRI image processing and analysis system may identify instances of structure in MRI flow data, e.g., coherency, derive contours and/or clinical markers based on the identified structures. The system may be remotely located from one or more MRI acquisition systems, and perform: perform error detection and/or correction on MRI data sets (e.g., phase error correction, phase aliasing, signal unwrapping, and/or on other artifacts); segmentation; visualization of flow (e.g., velocity, arterial versus venous flow, shunts) superimposed on anatomical structure, quantification; verification; and/or generation of patient specific 4-D flow protocols. An asynchronous command and imaging pipeline allows remote image processing and analysis in a timely and secure manner even with complicated or large 4-D flow MRI data sets.

A method and apparatus for false contour detection and removal for video coding are disclosed. The method includes performing false contour detection by detecting a map of false contour candidate pixels from input image data through sequential evolution of a step of acquiring false contour candidate pixels based on each of a plurality of features of a human visual system in a manner that decreases the number of pixels to be detected in each sequential step, and performing false contour removal by removing a false contour in the input image data according to the map of false contour candidate pixels.

The invention relates to an electric prospecting method. In the method, a transmitter transmits a signal and a receiver processes the received signal to obtain impulse response and frequency response. The electric prospecting method is characterized by comprising the following steps of: transmitting a pseudo random sequence by using the transmitter; carrying out correlation operation on a time sequence received by the receiver by using the pseudo random sequence so as to obtain time domain impulse response; converting the time domain impulse response to frequency domain so as to obtain frequency response; and carrying out fitting and inversion by using a double Cole-Cole model so as to obtain parameters of a complex resistivity method.

A borehole survey method is provided for processing continuous measurements of the earth's magnetic and gravitational fields obtained while drilling a borehole. The present invention improves borehole acquisition of targeted geological structures by substantially reducing continuous measurement errors attributable to noise, shock and vibrations from turning the drill bit against rock.

The invention provides a real-time and accurate pose estimation method based on a fiber-optic gyroscope, a speed sensor and a GPS. The unmanned vehicle local locating algorithm based on a vehicle body motion model is mainly based on the two-dimensional plane dead reckoning principle, the vehicle body current local pose is estimated through the vehicle body sensor speed and course information estimation at the previous time, and the gyroscope course accumulative error is compensated through a linear model, so the accuracy of the local locating system can be improved; and by using the iterative closet point algorithm to register GPS and the local pose measuring system pose estimation method, the local locating accumulative error can be corrected, so the random noise of the GPS can be effectively eliminated, and the pose accuracy can be maintained when the GPS is in complete failure condition or failed, and the running test result shows that the method provided in the invention can be used to well fuse multi-sensor information, and provide reliable and continuous locating information for unmanned vehicles in multi-tree and multi-building urban environments. Moreover, the method has the advantage of good real-time performance.

An ultrasonic phased array based method for extracting three-dimensional parameters of inner defects of a component is disclosed. The method includes detecting a component to be detected according tothe shape and size of the component, detecting inner defects of the component through moving a probe, displaying the inner defects in an ultrasonic phased array instrument, then storing data, acquiring section images corresponding to the inner defects of the component to be detected, then performing data storage through image information mainly including S-displayed images, subjecting collected defect display images to image processing, acquiring centers of mass of the processed defect section images, pointing positions of the centers of mass, calculating the area of the defects in each section image, replacing each complex-shape defect with a circle having the same area to perform area equivalent treatment on all images, reconstructing a three-dimensional defect model, and calculating three-dimensional parameters of the reconstructed inner defects of the component, with the three-dimensional parameters reflecting the inner structure of the component. The method is low in cost and lowin consumed time, devices are simple and easy to carry, and online detection can be achieved.

The invention, which is applicable to the transportation field, provides a short-term traffic flow change prediction method and device, a computer equipment and a storage medium. The method comprisesthe following steps: acquiring traffic flow data of a predicted road segment in real time; on the basis of the traffic flow data, constructing a traffic flow prediction model with a forgetting factor;and according to a particle filtering algorithm, eliminating random noises of the traffic flow prediction model and acquiring and outputting an optimal short-term traffic flow change prediction value. According to the short-term traffic flow change prediction method provided by the embodiment of the invention, the traffic flow prediction model is constructed by introducing the forgetting factor;and with the model, the traffic flow data can be updated and corrected in real time and thus the traffic flow change is fitted well, so that a phenomenon that the prediction precision is affected by the early collected traffic flow data because of the time-varying of the traffic flow is avoided and thus the good prediction effect is realized. Meanwhile, the random noise of the model is eliminatedby particle filtering, so that the accuracy and feasibility of the prediction are improved.

The determination of coherent events in a seismic image is disclosed including the following operational phases: a phase of selecting a segmentation criterion based on a variable and at least one sliding window on the zone and its characteristics, a phase of hierarchical segmentation, for overlapping positions of the sliding window, including a segmentation of the zone into n regions and for each pixel located at least once by a segmentation boundary; a phase of assigning to the non-located pixels a value of indices (EI and EIC) corresponding to a numerical or alphanumeric characteristic non-value; a phase of determining coherent events of the image by thresholding the indices (EI and EIC), that is by selecting only located pixels of the zone corresponding to values lower or higher than a fixed threshold.

The invention discloses a gait feature extraction method based on human body gravity center track analysis. The method comprises the steps of: S1, gait detection and tracking: original video images are converted into single channel gray scale images, and the images are smoothed through Gauss filtering, and the images are further converted into binary images; S2, positions of human body gravity centers are calculated, and gravity center coordinates of the image of each frame in a moving object in motion are connected in a same coordinate system to obtain a gravity center track of a pedestrian; and S3, gait waveforms after being subjected to denoising are input into a computer, and a harmonic wave amplitude corresponding to a K subharmonic frequency is calculated through the utilization of a formula, and a corresponding frequency spectrogram is drawn and output. According to the invention, problems encountered in present feature extraction can be solved, and a one-dimensional gait characteristic vector can be extracted from the complex gait images, so that further analysis, training and identification are convenient.

The invention provides a vector image generation method and system based on bitmap image adaptive segmentation. According to the method, filtering operation is carried out on a bitmap image through adoption of a bilateral filtering algorithm. Region segmentation processing is carried out on the bitmap image; pixels with similar values are merged into the same class according to a value of each pixel of the image; through repeated iteration, region segmented images of the image are obtained; and regions with excessively small areas are merged into adjacent regions. Region marked images of the segmented images are obtained; region edges are extracted through adoption of an optimized edge model and an extraction algorithm; edge line segments are fitted; and an edge curve of each region is determined. A color average value of a source image corresponding to each class of regions in the region marked images within the region is calculated; the average value is taken as a color of the current region; and a color list corresponding to the region is formed. A corresponding vector image file is generated according to the edge curve data and color list information of each region.

The invention discloses an orthogonal double grating based synchronous phase shifting common-path interference microscopy detection device and a detection method, and belongs to the technical field of optical interfering detection. The invention solves problems of complexity in processing process of detection data and low measurement accuracy in existing synchronous phase shifting interference microscopy detection methods. The method integrates the interfering microscopy technology with the orthogonal double grating common-path synchronous phase shifting technology, linear polarization parallel light after collimation and beam expansion is divided into object light and reference light by a first polarized beam splitter prism and a second polarized beam splitter prism to be ultimately converged at a rectangular window side-by-side, a computer obtains an interference figure containing four patterns by collection, and phase distribution of an object to be detected is obtained by calculating according to strength distribution of the four interference patterns. The orthogonal double grating based synchronous phase shifting common-path interference microscopy detection device and the detection method are suitable for measurement of three-dimensional shape and phase distribution of micro-objects.

The invention relates to a microscopic interference detecting device based on synchronous carrier phase shift and a detecting method of the microscopic interference detecting device, which belong to the field of optical interference detection and solve the problems that the existing synchronous carrier phase shift interference microscope method is low in light utilization rate and complex in data process. The microscopic interference detecting device comprises an optical source, a linear polarizing film, a first polarization splitting prism, a first collimation and beam expansion system, an object to be detected, a microobjective, a correcting objective, a first mirror, a second mirror, a second collimation and beam expansion system, a second polarization splitting prism, a lambda/4 wave plate, a rectangular window, a first flourier lens, a one-dimensional period optical grating, a second flourier lens, a polarizing film set, an image sensor and a computer. The detecting method comprises the steps that two phase shift interference images are obtained through once exposure collection after a defocused grating splitting technique and a polarization modulating technique are combined, and phase retrieval of an object is achieved by eliminating a zero frequency component in a differential phase reduction method. The microscopic interference detecting device based on the synchronous carrier phase shift and the detecting method of the microscopic interference detecting device, disclosed by the invention, are suitable for shape measurement of small objects.

A video signal processor recursively removes noise from luminance signal data, storing only one frame of the luminance signal data, and detects luminance motion by comparing the current and stored luminance data to decide whether to output the current color difference data, the average of the current color difference data and the color difference data one frame before, or the average of the current color difference data and the color difference data two frames before. The decision may also involve detection of color noise by comparison of the color difference data with the data one frame before, or detection of color motion by comparison of the color difference data with data two or four frames before. Color data stored for color noise detection may also be used for recursive color noise removal. Accurate noise reduction is possible with a comparatively small amount of memory.

The invention discloses a perspective-crossing gait recognition method based on 3D projection. The method mainly comprises the four steps of processing of two-dimensional images, extracting of gravity center trajectories, restoring of three-dimensional gait characteristics and three-dimensional perspective conversion. The method achieves gait recognition of gait characteristic accurate conversion among different shooting perspectives, the gait characteristics of flat images in a video camera can be restored into three-dimensional gait characteristics in a 3D space, and therefore a gait recognition process no longer needs multiple video cameras to achieve three-dimensional restoring. Meanwhile, due to the characteristics that the method extremely improves the arithmetic speed of perspective-crossing gait recognition and the method is free of influences of shooting perspectives, recognition can be carried out on the gait images shot by the video camera at any position, a gait recognition system developed by using the method can be applied to development of a simple door control system, and can also be applied to development of monitoring systems for streets, airports, public transportation and other public places with large visitor flow rates, and the intelligent monitoring level is raised to a new height.

The invention provides an orthogonal double-grating based detecting device for synchronous phase shift common-light path interference and a detecting method for the orthogonal double-grating based detecting device, belonging to the field of the detection of optical interference. The invention aims at solving the problem that the existing optical phase shift interference detecting method is complex and hard to operate, and is high in cost and low in measurement precision caused by a high-quality lambda/4 wave plate. The invention has the scheme that a light beam emitted out of a light source is incident into a light receiving surface of a collimating and beam expanding system through a polarizing film, an emergent light beam collimated and expanded by the collimating and beam expanding system is incident into a first lens through two lambda/4 wave plates, an object to be tested and a rectangular window opening, an emergent light beam collected by the first lens is incident into a second lens through the double gratings formed by a one-dimensional cyclic range grating and a one-dimensional cyclic phase shift grating, a diffraction light beam transmitted by the second lens is incident into a four-quadrant polarizing film set, an emergent light beam of the four-quadrant polarizing film set is received by an imaging sensor, and an image signal output end of the imaging sensor is connected with an image input end of a computer, and obtains the phase distribution of the object to be tested.

The invention discloses an infrared weak and small target detection method based on space-time joint local contrast, and relates to the field of infrared image processing and weak and small target detection. The method comprises the following steps: S1, constructing a sliding window with the size of 3*3, traversing a kth frame of image of an original sequence image, and obtaining a spatial domainlocal contrast response graph of the kth frame of image through spatial domain filtering; S2, calculating a variance value St of a continuous frame image, and obtaining a time domain local contrast response graph of the kth frame of image through time domain filtering in combination with variance value images of three adjacent frames of images; and S3, performing normalization processing on the time domain detection result and the space domain detection result, and combining the time domain detection result and the space domain detection result in a multiplicative fusion mode to obtain a space-time joint local contrast response of the kth frame of image. According to the method, spatial information and time information are fully utilized, the problems of low infrared weak and small targetdetection precision, scene robustness and the like caused by an existing method are solved, the detection performance and the low false alarm rate in infrared weak and small target detection under a complex background are improved, and the robustness of an algorithm is improved.

The invention discloses an interference detection device based on light-splitting synchronous phase shifting and a detection method. The interference detection device belongs to the field of optical interference detection. The invention aims to solve problems of difficulty and complexity in operation and low measurement precision of the conventional optical phase shifting interference detection method. The invention has the scheme that a light beam emitted from a light source is carried out collimation light expansion by a polarizing film and a collimation light expansion system to form a linearly polarized light; the linearly polarized light is divided into an object light beam and a reference light beam after passing through a first polarization light splitting prism; the object light beam and the reference light beam gathered on a second polarization light splitting prism pass through a lambda/4 wave plate, a rectangular window, a first Fourier lens, a one-dimensional period grating, a second Fourier lens, a depolarization light splitting prism and a four-quadrant polarizing film group in sequence; an interference pattern is generated on a plane of an image sensor; the interference pattern obtained by collection is processed by a computer; and phase distribution of an object to be detected is obtained.

The invention relates to a cloud service-based partial discharge transient-stage earth electric wave cloud detection method and device, wherein the method comprises the steps of: acquiring an earth electric wave signal; conducting filtering, amplification, analog-to-digital conversion to the acquired earth electric wave, wherein the analog-to-digital conversion consists of the steps of: rectifying a preset square wave signal into a direct current signal, comparing the direct current signal with the amplified earth electric wave, and reading the amplified earth electric wave by applying a binarization reading method; sending the digital earth electric wave to a cloud service side, conducting data processing to the digital earth electric wave through the cloud service side, and judging whether partial discharge occurs; and receiving the processed data returned by the cloud service side and a judgment result, displaying the processed data, and prompting according to the judgment result. The invention provides a detector accordingly. The method and device can overcome the defects that the on-site background noise is greatly influenced, and the data processing is complicated through the existing TEV partial discharge inspection, and improve the computation speed of the device and detection accuracy on partial discharge.

The invention discloses a common light path interference microscopy detection device and a method based on synchronization carrier frequency phase shift, belongs to the field of optics and overcomes the defects in prior art. The technical scheme includes that a light source is opened so that light beams emitted by the light source passes a line polaroid and are subjected to collimation beam expanding through a collimation beam expanding system to form a parallel polarized light, the light beams are emitted into a first beam splitter prism and subjected to reflection and transmission through the first beam splitter prism to finally form a reference light beam and an object light beam respectively, the reference light beam and the object light beam are gathered into a rectangular window side by side to sequentially pass through a first Fourier lens, a one-dimensional cycle optical grating, a second Fourier lens and a polariod group, polarized light beams emerged by the polariod group can generate a interference pattern on an imaging sensor plane, the interference pattern acquired by a computer is divided according to the size of a small window of the rectangular window to obtain two interference patterns, and the phase position distribution of an object to be detected can be obtained through calculation.

The invention relates to an interference detecting device based on synchronous carrier phase shift and a detecting method of the interference detecting device, which belong to the field of optical interference detection and solve the problems that the existing synchronous carrier phase shift interference detecting device is complex in structure and the existing detecting method is complex in data process. The interference detecting device comprises an optical source, a polarizing film, a collimation and beam expansion system, a first polarization splitting prism, an object to be detected, a first mirror, a second mirror, a second polarization splitting prism, a lambda/4 wave plate, a rectangular window, a first flourier lens, a one-dimensional period optical grating, a second flourier lens, a polarizing film set, an image sensor and a computer. The detecting method comprises the steps that light beams emitted by the light source are split into object light beams and reference light beams after passing through the first polarization splitting lens, two phase shift interference images are obtained through once exposure collection after a defocused grating splitting technique and a polarization modulating technique are combined, and phase retrieval of an object is achieved by eliminating a zero frequency component in a differential phase reduction method. The interference detecting device based on the synchronous carrier phase shift and the detecting method of the interference detecting device, disclosed by the invention, are suitable for shape measurement of small objects.

The invention discloses a method for partitioning an internal layer of a tubular structure, comprising the following steps: firstly, extracting a longitudinal section plane of tubular structure three-dimensional sequence data, extracting an internal layer contour line of the tubular structure on the longitudinal section plane, then converting the contour line of the longitudinal section plane into the contour line of a transverse section plane, sequentially, interpolating a contour point spline of the transverse section plane to obtain a spline contour, using wavelet transformation to generate a multi-scale image of the transverse section plane, converting the spline contour to be different scales and using the spline contour with different scales as the initial contour of active contour, then evolving the contour, finally combining the partition results of the active contour with different scales to obtain the final internal layer contour of the tubular structure. The technical proposal of the invention reduces the time of the initial contour. In order to improve the partition precision, the method uses the active contour to evolve the contour on multi scales.