Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

583 results about "Vanishing point" patented technology

A vanishing point is a point on the image plane of a perspective drawing where the two-dimensional perspective projections (or drawings) of mutually parallel lines in three-dimensional space appear to converge. When the set of parallel lines is perpendicular to a picture plane, the construction is known as one-point perspective, and their vanishing point corresponds to the oculus, or "eye point", from which the image should be viewed for correct perspective geometry. Traditional linear drawings use objects with one to three sets of parallels, defining one to three vanishing points.

Method and device for detecting road traffic abnormal events in real time

The invention provides a method and device for detecting road traffic abnormal events in real time. The method includes the steps of monitoring a road, obtaining a plurality of frames of continuous monitor images, extracting bright white segments from the monitor images, obtaining lane lines and lane end points through processing, building a lane model, determining a bidirectional detection area of a lane according to the lane model, detecting a moving object in the bidirectional detection area according to a Gaussian mixture model background subtraction method, determining the position of the moving object, building the mapping relation between the moving target and an actual vehicle according to the position of the moving target in the multiple frames of continuous monitor images by the adoption of a posterior probability splitting and merging algorithm and a feature point matching and tracking method, obtaining the running track and running speed of the actual vehicle, detecting the lane model and the running track and running speed of the actual vehicle according to a prestored road traffic abnormal behavior semantic model, and judging whether the road traffic abnormal events exist or not. The method has the advantages of being intelligent, high in accuracy and the like.
Owner:TSINGHUA UNIV +1

Method for calibrating external parameters of monitoring camera by adopting reference height

InactiveCN102103747AMeet application needsGuaranteed calibration measurement accuracyImage analysisTerrainHorizon
The invention discloses a method for calibrating external parameters of a monitoring camera by adopting reference height, which comprises the following steps of: far vanishing point and lower vanishing point-based vision model description and related coordinate system establishment; projected coordinate calculation of reference plumb information-based far vanishing points and lower vanishing points in an image plane; reference height calibration-based camera height, overhead view angle and amplification factor calculation; design of a reference plumb direction-based horizon inclination angle calibration tool; and design and use of perspective projection model-based three-dimensional measurement software and three tools for three-dimensional measurement, namely an equal height change scale, a ground level distance measurement scale and a field depth reconstruction framework. The calibrating method is simple and convenient in operation, quick in calculation and high in measurement precision. The reference can be a pedestrian, furniture or an automobile; and a special ground mark line is not needed. The method allows the camera to be arranged at a low place, and the shooting overhead view angle is slightly upward as long as the bottom of the reference can be seen clearly in the video and the ground level coordinate system is definite.
Owner:INST OF ELECTRONICS CHINESE ACAD OF SCI

Real-time lane line detection method

The invention provides a real-time lane line detection method. According to the real-time lane line detection method, an interested area is determined through the position of a current frame vanishing point, and an upper half image where no lane lines exist is removed, and therefore, the processing time of each frame of image can be decreased; edge point scanning is performed at two directions from inside to outside of the interested area, and what is detected every time is the inner side of a lane line which is most adjacent to vehicles on a lane, and except for the interference of other edge points, jigger will not be generated because of the width of the lane line, and since an image is divided into two half parts of detection lane lines from the position of the vanishing point, a situation that two detected straight lines are located at one side of the vanishing point when the entire image is detected can be avoided, and thus, the accuracy of the detection can be improved; and further, when Hough transform lane line detection is performed, only straight lines in a range of straight lines which can form a certain included angle with a horizontal line are selected, and therefore, the accuracy of the detection can be improved, and time for calculating Hough weight of straight lines that are not in the range of the straight lines can be saved. With the real-time lane line detection method of the invention adopted, lane line detection at highways and rural areas where roads are in good condition can be realized rapidly, accurately and stably.
Owner:厚普清洁能源(集团)股份有限公司

Multi-camera-based multi-objective positioning tracking method and system

The invention discloses a multi-camera-based multi-objective positioning tracking method. The method is characterized by comprising the following steps: installing a plurality of cameras at a plurality of visual angles firstly, planning a public surveillance area for the cameras, and calibrating a plurality of height levels; sequentially implementing the steps of foreground extraction, homography matrix calculation, foreground likelihood fusion and multi-level fusion; extracting positioning information which is based on selected a plurality of height levels and obtained in the step of foreground likelihood fusion; processing the positioning information of each level by using the shortest path algorithm so as to obtain the tracking paths of the levels; and after combining with the processing results of foreground extraction, completing the multi-objective three-dimensional tracking. By using the method disclosed by the invention, in the process of tracking, the vanishing points of the plurality of cameras are not required to be calculated, and a codebook model is introduced for the first time for solving the multi-objective tracking problem, thereby improving the accuracy of tracking; and the method has the characteristics of good stability, good instantaneity and high precision.
Owner:DALIAN NATIONALITIES UNIVERSITY

Measuring method for length, width and height of vehicle based on RGB-D camera

The invention discloses a measuring method for length, width and height of a vehicle based on an RGB-D camera. The method comprises the steps of acquiring a clear vehicle image in a camera short-distance mounting manner, calibrating the camera according to a calibrating method based on a disappearing point, obtaining an internal parameter and an external parameter of the camera, realizing three-dimensional point cloud conversion of a vehicle target in a world coordinate system through a camera depth image solution, and acquiring three-dimensional coordinate information of the external surfaceof the vehicle; acquiring the three-dimensional coordinate of the external surface of the vehicle by means of prior knowledge and an image processing method, splicing a vehicle image according to sequence patterns in a vehicle motion process through a registering method, and realizing three-dimensional measurement to the profile of the vehicle. The measuring method overcomes defects of high equipment requirement and tedious operation in a traditional method and realizes high calibration precision. The actual displacement of the vehicle is comprehensively analyzed through a matching relation ofpoints which correspond with the same position of the vehicle in the image sequence, thereby realizing relatively high registering precision. The measuring method further has advantages of realizingaccurate splicing of the vehicle side surfaces, reducing vehicle length measurement error and improving accuracy in splicing the vehicle side surfaces.
Owner:CHANGAN UNIV

Three-lane detection method based on image morphological segmentation and region growing

The present invention relates to a three-lane detection method based on image morphological segmentation and region growing. The method comprises: a method for, by using a shape of a lane mark and a relative gray level of a roadway, performing segmentation on the lane mark by means of image morphology; a method for fitting a vanishing point by using a weighted least square method; and a method for forming a region of interest (ROI) of the lane mark by a region growing method and iteratively searching for a feature point of the lane mark. According to the three-lane detection method based on image morphological segmentation and region growing, aimed at the problem of perception of a vehicle-mounted visual system of an intelligent vehicle to a multi-lane road in a process of driving on the urban structural multi-lane road, a method of carrying out image morphology preprocessing and carrying out iterative solution on the lane mark is adopted to adapt to a multi-lane environment. The method is novel in algorithm, high in adaptability, relatively high in illumination robustness, small in computation amount and easy to implement by programming, so that a module of the vehicle-mounted visual system is improved, and the efficiency and environmental adaptability of an intelligent vehicle environment sensing module are further improved.
Owner:BEIJING UNIV OF TECH

A structured light parameter calibrating apparatus and method based on a front-film-plated plane mirror

The invention discloses a structured light parameter calibrating apparatus and method based on a front-film-plated plane mirror. The method comprises the following steps: a front-film-plated plane mirror and a plane glass target are placed in front of a camera; the camera simultaneously shoots the image of the plane glass target and a mirror image of the plane glass target; a virtual binocular measurement model is established; optimal solutions of a rotation matrix from a front-film-plated plane mirror coordinate system to a camera coordinate system and a translation vector are obtained by a nonlinear optimization method; image vanishing point solving is carried out on optional feature points by the least squares method; white printing paper is placed in front of the front-film-plated plane mirror, and the camera takes the actual light bar image and the mirror image light bar image; and the center point of the light bar image is extracted to calculate the three-dimensional coordinates of matching points to solve an optical plane equation. According to the invention, the light bar quality is improved and the light bar center extraction precision is raised; feature points with the position precision of the micron order are provided to obtain more calibration points; higher calibration precision is realized; and the calibration result is more stable.
Owner:BEIHANG UNIV

Robot synchronous positioning and map construction method and system

The invention discloses a robot synchronous positioning and map construction method based on line segment features and line segment vanishing points, and the robot synchronous positioning and map construction method is applied to the positioning and map construction of a robot in an unknown environment. The robot synchronous positioning and map construction method comprises the steps of: extracting line segment features, intersection points and vanishing points from images, establishing line segment matching between the images according to the intersection points, estimating camera poses according to line segment matching results, and selecting a new keyframe; and inserting the keyframe into a map, calculating three-dimensional coordinates of the newly-added line segment features, performing cluster adjustment on local map, and removing outlier observation; and performing closed-loop detection and global map optimization based on the intersection points. The invention further discloses a synchronous positioning and map construction system. The robot synchronous positioning and map construction method and the robot synchronous positioning and map construction system can be appliedto the positioning and map construction of the robot in the unknown environment, and is particularly suitable for structured or semi-structured scenes, such as indoor environments, outdoor environments with buildings, and the like.
Owner:上海阅面网络科技有限公司

Structure optical parameter demarcating method based on one-dimensional target drone

The invention belongs to the technical field of measurement, and relates to an improvement to a calibration method of structured light parameters in 3D vision measurement of structured light. The invention provides a calibration method of the structured light parameters based on a one-dimensional target. After a sensor is arranged, a camera of the sensor takes a plurality of images of the one-dimensional target in free non-parallel motion; a vanishing point of a characteristic line on the target is obtained by one-dimensional projective transformation, and a direction vector of the characteristic line under a camera coordinate system is determined by the one-dimensional projective transformation and a camera projection center; camera ordinates of a reference point on the characteristic line is computed according to the length constraint among characteristic points and the direction constraint of the characteristic line to obtain an equation of the characteristic line under the camera coordinate system; the camera ordinates of a control point on a plurality of non-colinear optical strips are obtained by the projective transformation and the equation of the characteristic line, and then the control point is fitted to obtain parameters of the structured light. In the method, high-cost auxiliary adjustment equipment is unnecessary; the method has high calibration precision and simple process, and can meet the field calibration need for the 3D vision measurement of the large-sized structured light.
Owner:BEIHANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products