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178 results about "Haar wavelet" patented technology

In mathematics, the Haar wavelet is a sequence of rescaled "square-shaped" functions which together form a wavelet family or basis. Wavelet analysis is similar to Fourier analysis in that it allows a target function over an interval to be represented in terms of an orthonormal basis. The Haar sequence is now recognised as the first known wavelet basis and extensively used as a teaching example.

Consistent lighting method under falsehood-reality fused environment

InactiveCN102096941ARealize full-frequency ambient lighting rendering effectImprove realism3D-image renderingComputer graphics (images)Bidirectional reflectance distribution function
The invention discloses a consistent lighting method under a falsehood-reality fused environment, comprising the following steps: shooting a high dynamic range image reflecting a real environment, of a small mirror-surface sphere in a real scene, and acquiring an environmental lighting map of the real scene; preprocessing the environmental lighting map of the real scene and surface reflection attributes of a virtual object; preprocessing the environmental lighting of the real scene to generate environment lighting on a unit small sphere under local coordinates corresponding to all normal vectors to obtain Haar wavelet coefficients of the environment lighting; preprocessing a bidirectional reflection distribution function to generate slices of the bidirectional reflection distribution function on the unit hemisphere under all sight directions to obtain Haar wavelet coefficients of the slices; and drawing a falsehood-reality fused environment, indexing the wavelet coefficients of the environment lighting and the slices of the bidirectional reflection distribution function according to a normal vector of an apex of the virtual object and the sight directions, calculating a vector product of the coefficients to obtain an apex drawing color, and meanwhile, accelerating by adopting GPU (Graphics Processing Unit). The consistent lighting method can be used for efficiently realizing afull-range environment lighting drawing effect under the falsehood-reality fused environment.
Owner:BEIHANG UNIV

Quick deciding method for division of HEVC intraframe coding units

The invention discloses a quick deciding method for division of HEVC intraframe coding units, which respectively adopts corresponding strategy according to the depth of the CU to decide whether the CU is continuously divided or whether to skip the prediction process of the CU. Brightness variations of each CU in the horizontal, vertical and diagonal directions are computed by using Haar wavelet transform, and the texture complexity of the CU is determined according to the magnitudes of the variations. For the CU with the depth of 0 or 1, if all the brightness variations in the three directions are more than a threshold, the current CU needs to be divided continuously. For such CU, the prediction process based on rate distortion optimization of the current CU is to be skipped and directly divided into the next layer. For the CU with the depth of 2 or 3, if all the brightness variations in the three directions are more than a threshold, the current CU is not divided continuously. According to the method, the statistic characteristics and texture characteristics of the CU division distribution are combined, whether the division of the CU needs to be stopped or continued can be effectively predicted, and thereby a quadtree is effectively pruned and redundant coding nodes are skipped. The computation complexity of intraframe coding of the HEVC coder can be significantly reduced.
Owner:TONGJI UNIV

Multi-resolution path planning method for micro unmanned aerial vehicle under influence of wind field

The invention discloses a multi-resolution path planning method for a micro unmanned aerial vehicle under the influence of a wind field. The multi-resolution path planning method includes six steps as follows: firstly, obtaining an environmental zone for the path planning of the aerial vehicle; secondly, selecting a basic function for wavelet transformation; thirdly, creating a flying environment cost function under the influence of the wind field; fourthly, reconstructing a multi-resolution flying environment cost function by using a Haar wavelet grid decomposition method; fifthly, generating an environmental weighted graph by using a multi-resolution environment cost function value; and sixthly, looking for the optimal path. According to the multi-resolution path planning method, the factors such as the computing power of an airborne computer, the detection range of a sensor, the distribution of an obstacle, the distribution and intensity of the wind field and the like are considered in the process of determining different resolution levels in the environmental zone, so that the path planning efficiency is improved. Moreover, the multi-resolution path planning method is simple, reliable and practical, and is suitable for the online path planning of the low-altitude micro unmanned aerial vehicle under the influence of the wind field.
Owner:BEIHANG UNIV

Continuous chemical process fault detection method

The invention relates to a continuous chemical process fault detection method. The continuous chemical process fault detection method comprises the following steps that (1) a linear regression model of a vector Xj and a vector Y is built, and a regression constraint function is introduced; (2) data compression is carried out through haar wavelet transformation to improve computational efficiency; (3) a regression constraint construction sparse pivot element model with the addition of 1-norm and 2-norm is built, and an optimal solution of a sparse pivot element is worked out through derivation of the SPCA algorithm; (4) the optimal threshold value of the T2 statistic and the optimal threshold value of the SPE statistic are estimated through the kernel density estimation (kde) method; (5) calculation of the T2 statistic and the SPE statistic is conducted on fault data, and the value of the T2 statistic and the value of the SPE statistic of the fault data are obtained in sequence; (6) whether a fault exists in the data is detected. According to the continuous chemical process fault detection method, the data size related to a pivot element after sparsity is reduced, so that the calculated quantity is reduced, the computation time is shortened, real-time performance of monitoring is improved, and accuracy and efficiency of fault detection can be improved.
Owner:EAST CHINA UNIV OF SCI & TECH

Watershed texture imaging segmenting method based on morphology Haar small wave texture gradient extraction

The invention discloses a segmentation method of a watershed texture image on the basis of morphological Haar wavelet gradient extraction, which relates to the technical filed of image processing and aims at solving the excessive segmentation problem of watershed texture image segmentation. The method not only can reduce excessive segmentation, but also is much better than other post processing methods solving the problem of excessive segmentation in arithmetic speed. The steps for realizing the method are as follows: (1) a texture gradient image TG is extracted by carrying out morphological Haar wavelet conversion to the original texture image; (2) after circumrotating by 90 degrees, the original image is used for extracting a texture gradient image RTG with a morphological Haar wavelet; (3) the texture gradient image RTG and the texture gradient image TG are subjected to circumrotation weighting to obtain a texture gradient image G; (4) morphological filtering is carried out to the texture gradient image G to obtain a texture gradient image OCG after being smoothed; and (5) marker-watershed segmentation is carried out to the texture gradient image OCG to obtain the final texture segmentation result. Compared with the image segmentation standards, the image segmentation result of the method is validated to basically meet standards.
Owner:XIDIAN UNIV

Binocular vision-based unmanned aerial vehicle aerial autonomous refueling fast docking navigation method

InactiveCN106934809AAccurately determineFeature points are accurate and usefulImage enhancementImage analysisMachine visionImaging processing
The invention relates to a binocular vision-based unmanned aerial vehicle aerial autonomous refueling fast docking navigation method and belongs to the machine vision and image processing field. The method includes the following steps that: a binocular camera system with an optical filter shoots a refueling taper sleeve with an optical marker lamp, so that a left image and a right image are obtained; gray processing, binarization and median-value filtering are performed on the left image and the right image sequentially, all communicated regions in the left image and the right image are searched and marked through adopting a regional growth method, and the centroids of each of the communicated regions are calculated and are adopted as feature points; improved haar wavelet transform is adopted to describe all the feature points, and the description vectors of all the feature points are obtained, the feature points of the left image and the right image are matched through adopting the minimum Euclidean distance method, so that the feature point pars of the left image and the right image are obtained; and the three-dimensional coordinates of the feature points are calculated by using a binocular vision principle, and the least squares method is adopted to perform spatial circle fitting on the three-dimensional coordinates, and the end surface circle curve of the refueling taper sleeve is obtained, and the center, normal vector and radius of the circle are obtained through calculation.
Owner:XIAMEN UNIV

Cheating-prevention method in face recognition system

InactiveCN106446772AExcellent anti-spoofing performanceReduce consumptionSpoof detectionFeature vectorComputation complexity
The present invention discloses a cheating-prevention method in a face recognition system. The method comprises the steps of 1 obtaining a face gray-scale image; 2 carrying out the equivalent characteristic coding on the pixel points of the face gray-scale image obtained in the step 1 and then obtaining 59 dimensions of ULBP characteristic vectors by the histogram statistic; 3 carrying out the four-level Haar wavelet decomposition on the face gray-scale image; 4 splicing the characteristic vectors and then sending to a trained support vector machine (SVM) classifier, and predicting a label via a decision function; 5 collecting a set of positive and negative face samples to train and test the SVM classifier capable of discriminating the face cheating; 6 training the SVM, and then utilizing a test set in the step 5 to test three trained SVM, thereby selecting the SVM of a kernel function of the best performance to discriminate the true and false face images. Compared with the prior art, the greatest advantages of the present invention are that the cheating-prevention method in the face recognition system is small in calculation complexity, saves the time and space consumption, has an excellent face cheating-prevention performance, and can be used to guarantee the safety of the face recognition system.
Owner:TIANJIN UNIV

Method and device for improving measurement precision of gas analyzer

The invention discloses a device capable of improving measurement precision of gas analysis instrument, which comprises a filter wheel which is provided with a plurality of infrared filters; an electric motor which is used to drive the an infrared stationary light source and a monolithic system, wherein, a plurality of infrared filters are arranged on the filter wheel, the electric motor is used to drive the filter wheel to rotate against a preset frequency; an infrared stable light source which is used to irradiate a detecting gas cell through the infrared filters and is provided with an infrared sensor behind the detecting gas cell to receive the beam from the infrared stable light source; a single chip system which is used to control the drive of the electric motor and conduct wavelet contraction thresholds filtering on the signals received by the infrared sensor. The method and device of the invention are optimized by decomposing Haar wavelet and rebuilding wavelet, multiplication is transferred to addition in wavelet transform and meanwhile section wavelet filtering is adopted, which reduces operation volume, can be applied on a single chip system or imbedded system, effectively reducing the noise signals of gas analysis instrument, improving the measurement precision and decreasing the dependence on the hard circuit filter and model selection.
Owner:SHENZHEN MINDRAY BIO MEDICAL ELECTRONICS CO LTD

Wavelet domain-based method for weighting fractional differential image digital watermark

The invention provides a wavelet domain-based method for weighting a fractional differential image digital watermark, which mainly solves the problem that the high-frequency coefficient of an image undergoing wavelet decomposition is susceptible to extraneous noises and conventional image processing. The method comprises the implementation steps of: doing two different orders of differentials for a sinusoidal signal by utilizing a fractional order Cauchy formula; respectively carrying out discrete sampling and superposing by utilizing a given weight to generate a pseudorandom sequence and adding the pseudorandom sequence with a watermark pixel value to realize watermark scrambling; carrying out two-stage decomposition on a carrier image by utilizing a Haar wavelet and embedding the scrambled watermark information in the carrier image through the exchanged and decomposed high-frequency coefficient; and through comparing the high-frequency coefficient undergoing the two-stage decomposition by utilizing the Haar wavelet, extracting the scrambled watermark and subtracting the pseudorandom sequence to realize watermark recovery. The method provided by the invention has the advantages of strong anti-attack ability and good safety of the image, and can be applied to copyright protection, restriction of illegally spreading audiovisual products, individual privacy protection, identification hiding and high-tech crime prevention.
Owner:XIDIAN UNIV

Iris preprocessing algorithm based on space distance circle marking edge detection

The present invention provides an iris preprocessing algorithm based on space distance circle marking edge detection. The method comprises a first step of performing image acquisition on an iris of a human eye through a photographing device, thus to obtain an original gray level image; a second step of carrying out noise processing on the acquired image by using a median filtering algorithm; a third step of decomposing the iris image into four subband images by utilizing Haar wavelets; a fourth step of carrying out edge detection on an inner edge of the iris by using Canny operators; a fifth step of carrying out precision positioning of an inner circuit of the iris by using a sub pixel circle positioning algorithm; and a sixth step of carrying out accurate positioning on an outer circuit by using a method of increasing searching radius step length. According to the iris preprocessing algorithm based on the space distance circle marking edge detection, the Canny operators are utilized for filtering, enhancement and detection, the sub pixel circle positioning algorithm is utilized for carrying out accurate positioning of the inner circle of the iris, and the efficiency of circle detection operators is promoted by using the method of increasing the searching radius step length, thereby realizing accurate positioning of the outer circle of the iris, raising the detection precision, and promoting the detection speed.
Owner:NANJING ANSUI INTELLIGENT TECH CO LTD

Method for realizing quantum circuit design through quantum Haar wavelet transformation

The invention provides a method for realizing quantum circuit design through quantum Haar wavelet transformation, and belongs to the field of quantum information processing. According to the method, the existing quantum Fourier transform implementing technology is perfected and improved, and implementing circuits of two pieces of multi-layer quantum Haar wavelet transformation and two pieces of multi-layer quantum Haar wavelet inverse transformation are established separately by using extended tensor product and basic quantum bit gate (comprising quantum bit controlled door and single quantum bit gate). Based on analysis of the complex rates of the implementing circuits of the quantum Haar wavelet transformation and the quantum Haar wavelet inverse transformation, the complex rates of the implementing circuits of the two pieces of multi-layer quantum Haar wavelet transformation and the two pieces of multi-layer quantum Haar wavelet inverse transformation are Theta(n2) for one data set with 2n elements, and other typical and rapid Haar wavelet transformation cannot achieve the aim. The method is suitable for the fields of algorithms such as compression, denoising, encryption and decryption of images of actual information processing application, and has important significance in popularization of perfection and application of a quantum computing theory.
Owner:GUANGXI NORMAL UNIV

Application method of vision multichannel model in stereoscopic video quality objective evaluation

The invention belongs to the field of video and image processing, and provides a stereoscopic video objective quality evaluation method which is more suitable to the human vision system related characteristic and effective. A new stereoscopic video objective quality evaluation method can more accurately evaluate the quality of the stereoscopic video, and pushes the development of the stereoscopic imaging technology at the same time. An application method of a vision multichannel model in stereoscopic video quality objective evaluation comprises the following steps: modelling the vision multichannel model by use of haar wavelets, firstly performing three-level wavelet transformation on an absolute difference map of a key frame so as to simulate the human eye multichannel characteristic by resolving the absolute difference map into different directions and frequency ingredients; and evaluating the different components obtained through transformation by applying SSIM so as to obtain the corresponding objective quality; obtaining the single quality of each key frame by use of the wavelet inverse transformation; and finally weighting the quality of the key frame by use of the weight of the key frame so as to obtain the complete stereoscopic video quality. The application method of the vision multichannel model is mainly applied to the video and image processing.
Owner:TIANJIN UNIV
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