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To achieve the calibration parameters of vision measurement system, this paper presents a new camera calibration method based on grid recognition. The calibration is implemented by acquiring the corresponding relations between the world coordinates and pixel coordinates of the planar gridding target image captured by camera. Meanwhile, the pixel coordinates of the target image are detected separately...
The objective of the paper was to design and development of a stereo vision system to build 3D model for underwater objects. The developed algorithm first enhance the underwater image quality then construct 3D model by using iterative closest point (ICP) algorithm. From the enhanced images feature points are extracted and feature based matching was done between these pair of images. Epipolar geometry...
Generic imaging models can be used to represent any camera. These models are specially suited for non-central cameras for which closed-form models do not exist. Current models are discrete and define a mapping between each pixel in the image and a straight line in 3D space. Due to difficulties in the calibration procedure and model complexity these methods have not been used in practice. The focus...
This work constructs a real-time ball capture robot using the stereo computer vision technique and a novel biologically inspired 3D trajectory prediction method. The proposed trajectory prediction algorithm emulates the flight-to-light flight behaviour of the moth. The developed system can catch a flying ball according to the early prediction position generated from the proposed algorithm. The capture...
A 1D object is a segment with several known-distance markers, and calibration methods with 1D objects are more flexible than those with 2D/3D objects. Under the pinhole camera model, it is proved that the calibration with free-moving 1D objects is not possible. For a central catadioptric camera setup, can the camera be calibrated by a 1D object under general motions? In this paper, we prove that a...
Camera calibration is a necessary step to extract 3D information from 2D images. Since the 1D object is easy to construct and without self-occlusion, the 1D calibration proposed by Zhang has received many attentions. However, the progress in 1D calibration mainly focuses on reducing restrictions on the 1D object's movements. The calibration accuracy still demands improvements. In this paper, the computational...
Image epipolarization in photogrammetry is a common technique used to determine relative orientation based on collinearity and coplanarity, which usually requires scenes with multiple images. In general, these processes require internal orientation parameters, therefore the knowledge of camera calibration and relative orientation parameters between images. This paper presents a new algorithm that...
To monitor fluid flow dynamically and obtain more reliable gas reservoir information of 3D time-lapse seismic data, in this paper we present a 4D-AVO inversion algorithm, in which visualization technology, cross-correlation technology, time and phase shift theory, matched filtering algorithm and normalization technology are used to correct and analyze time-varying seismic data after AVO inversion...
The paper presents such a low-cost and simple 3D Scanner System. The necessary hardware is a hand-held line laser and two same standard cameras. The 3D scanner system is built by using simple methods to obtain 3D information of object. So it is very easy-to use, and the results can be satisfied by normal users.
This paper proposes a technique of camera calibration to calibrate a camera. It is easy for the proposed technique to extract the camera parameters with only one image using an iteration method. In this paper, radial and tangential lens distortion is modeled. The proposed technique divides original parameters into block of parameters. Each block of parameters is computed by minimizing a nonlinear...
Computer aided surgery (CAS) often involves the use of instrument, implants and other interactive device whose pose is tracked in real time so as to provide navigated positioning of the instrument to guide the surgeon carrying out the operation. The infrared tracking system has been proved to be a valuable alternative to tracking system based on other technologies, such as magnetic, acoustic, gyroscopic...
This paper proposes a novel approach for fast 3D reconstruction of an object inside a scene by using Inertial Measurement Unit (IMU) data. A network of cameras is used to observe the scene. For each camera within the network, a virtual camera is considered by using the concept of infinite homography. Such a virtual camera is downward and has optical axis parallel to the gravity vector. Then a set...
Above all, we pointed out that the basis of the calibration algorithm based on the grid points is the matrix, which indicates the mapping relationship between the target surface and the image surface. But to our disappointment, it is the correspondence problem of the calibration points that exists in the current way to calculate it. Therefore, the fiducial marker system is used for reference here,...
Camera calibration using patterns is widely used in computer vision and industry. The accuracy of calibration depends on the accuracy of the pattern. A high accuracy pattern is usually difficult to manufacture in labs. In this paper, we propose to use two images of two identical industrial objects as natural calibration patterns. The corresponding line segments on the objects are used for a nonlinear...
In existing literature, the response of a Pyroelectric Detector (PED) has been modeled almost exclusively with slow varying excitation signals having the shape of either a square or sinusoidal wave. Their naturally slow thermal response (~1 second) is not favourable in view of their use in a variety of faster existing or emerging applications. Even so, PEDs are still good candidates for e.g. mid-infrared...
Camera parameters estimation is an important issue in machine vision research area. This paper proposes a new method to find pan and tilt of camera in sport scene on the basis of vanishing points. Vanishing point (VP) of parallel lines is the image of the point at infinity, which corresponds to the projection of the intersection of parallel lines at infinity. According to projective geometry constraint,...
In order to solve the calibration of camera extrinsic parameters problem in texture mapping,this paper presents a geometric calibration method based on four point pairs.The first one select three points in the world coordinate system and calculate their coordinates in the camera coordinate system(world point, light heart, and image point are colinear). Transform the coordinates to a reference coordinate...
Camera parameters estimation is an important issue in machine vision. This paper proposes a new method to find translation and rotation matrix of camera in sport scene on the basis of vanishing points. Vanishing point (VP) of parallel lines is the image of the point at infinity, which corresponds to the projection of the intersection of parallel lines at infinity. According to projective geometry...
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