scholarly journals Analysis of Fish-Eye Lens Camera Self-Calibration

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1218 ◽  
Author(s):  
Kang Choi ◽  
Yongil Kim ◽  
Changjae Kim
Keyword(s):  
Test Object ◽  
Focal Length ◽  
Calibration Method ◽  
The Other ◽  
Eye Lens ◽  
Wide Field ◽  
Self Calibration ◽  
Type Test ◽  
Fish Eye ◽  
Test Objects

The fish-eye lens camera offers the advantage of efficient acquisition of image data through a wide field of view. However, unlike the popular perspective projection camera, a strong distortion effect appears as the periphery of the image is compressed. Such characteristics must be precisely analyzed through camera self-calibration. In this study, we carried out a fish-eye lens camera self-calibration while considering different types of test objects and projection models. Self-calibration was performed using the V-, A-, Plane-, and Room-type test objects. In the fish-eye lens camera, the V-type test object was the most advantageous for ensuring the accuracy of the principal point coordinates and focal length, because the correlations between parameters were relatively low. On the other hand, the other test objects were advantageous for ensuring the accuracy of distortion parameters because of the well-distributed image points. Based on the above analysis, we proposed, an accurate fish-eye lens camera self-calibration method that applies the V-type test object. The RMS-residuals of the proposed method were less than 1 pixel.

scholarly journals Proposed New AV-Type Test-Bed for Accurate and Reliable Fish-Eye Lens Camera Self-Calibration

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2776
Author(s):  
Kang Hyeok Choi ◽  
Changjae Kim
Keyword(s):  
Outer Part ◽  
Calibration Procedure ◽  
Geometric Distortion ◽  
Eye Lens ◽  
Wide Field ◽  
Test Bed ◽  
Self Calibration ◽  
Type Test ◽  
Balanced Distribution ◽  
Fish Eye

The fish-eye lens camera has a wide field of view that makes it effective for various applications and sensor systems. However, it incurs strong geometric distortion in the image due to compressive recording of the outer part of the image. Such distortion must be interpreted accurately through a self-calibration procedure. This paper proposes a new type of test-bed (the AV-type test-bed) that can effect a balanced distribution of image points and a low level of correlation between orientation parameters. The effectiveness of the proposed test-bed in the process of camera self-calibration was verified through the analysis of experimental results from both a simulation and real datasets. In the simulation experiments, the self-calibration procedures were performed using the proposed test-bed, four different projection models, and five different datasets. For all of the cases, the Root Mean Square residuals (RMS-residuals) of the experiments were lower than one-half pixel. The real experiments, meanwhile, were carried out using two different cameras and five different datasets. These results showed high levels of calibration accuracy (i.e., lower than the minimum value of RMS-residuals: 0.39 pixels). Based on the above analyses, we were able to verify the effectiveness of the proposed AV-type test-bed in the process of camera self-calibration.

scholarly journals BIFOCAL STEREO FOR MULTIPATH PERSON RE-IDENTIFICATION

2017 ◽  
Vol XLII-2/W8 ◽  
pp. 37-44 ◽  
Author(s):  
G. Blott ◽  
C. Heipke
Keyword(s):  
Focal Length ◽  
Image Resolution ◽  
Field Of View ◽  
Eye Lens ◽  
Single Camera ◽  
Identification Performance ◽  
Stereo Cameras ◽  
Working Distance ◽  
3D Information ◽  
Fish Eye

This work presents an approach for the task of person re-identification by exploiting bifocal stereo cameras. Present monocular person re-identification approaches show a decreasing working distance, when increasing the image resolution to obtain a higher reidentification performance. We propose a novel 3D multipath bifocal approach, containing a rectilinear lens with larger focal length for long range distances and a fish eye lens of a smaller focal length for the near range. The person re-identification performance is at least on par with 2D re-identification approaches but the working distance of the approach is increased and on average 10% more re-identification performance can be achieved in the overlapping field of view compared to a single camera. In addition, the 3D information is exploited from the overlapping field of view to solve potential 2D ambiguities.

Radial Distortion Correction of Fish-Eye Lens Using Straight Lines

2013 ◽  
Vol 432 ◽  
pp. 364-367
Author(s):  
Jong Eun Ha
Keyword(s):  
Distortion Correction ◽  
Eye Lens ◽  
Wide Field ◽  
Lens Model ◽  
Radial Distortion ◽  
Straight Line ◽  
Wide Field Of View ◽  
Planar Pattern ◽  
Straight Lines ◽  
Fish Eye

Fish-eye lens is used in various applications because it can give wide field of view. But, it deviates from the conventional pin-hole camera assumption. It has large radial distortion compared to the conventional lens. In this paper, we present an algorithm for radial distortion correction of fish-eye lens using the property of straight line. First, we estimate the center of radial distortion using the algorithm of Hartely and Kang [4]. We adopt fish-eye lens model of Devernay and Faugeras [5] and estimate the parameter thorough searching. We use planar pattern with chessboard and generate undistorted points by given parameter value. We evaluate the correctness of the parameter by checking the distance of a point to the fitted line. In experiments, we compare proposed algorithm with Wang et al. [6]. Proposed algorithm gives more stable result with less distortion error.

Study the Fisheye Staring Video Surveillance System of nothing Blind-Zone Based on the DaVinci Chip

2013 ◽  
Vol 846-847 ◽  
pp. 574-577
Author(s):  
Jian Hui Wu ◽  
Guo Yun Zhang ◽  
Long Yuan Guo ◽  
Shuai Yuan
Keyword(s):  
Video Surveillance ◽  
Surveillance System ◽  
Imaging System ◽  
Calibration Method ◽  
Eye Lens ◽  
Video Surveillance System ◽  
Blind Zone ◽  
Hardware System ◽  
Imagery Processing ◽  
Fish Eye

A staring and nothing blind-zone video surveillance system was designed based on the DSP chip of TMS320DM6467 and the fish-eye lens which has ultra-view field. This fisheye lens has 185 degree field of view, and make the system has 360 degree panorama and nothing blind-zone monitoring which used two fish-eye lens imaging system. Firstly, this paper designed the panorama imaging system, and then studied the calibration method for it. The hardware system used the multimedia imagery processing chip of TMS320DM6467 which has dual core processor and can processing the fish-eye image real time. The experiment shows the fisheye image had 360 degree sphere with nothing blind-zone for surveillance area and the hardware of processing center can work stable. This system can intelligent surveillance when upload the algorithm.

An Accurate and Real-Time Focal-Length Self-Calibration Method Based on Infinite Homography between Vanish Points

2014 ◽  
Vol 34 (5) ◽  
pp. 0515003 ◽  
Author(s):  
蔡鸣 Cai Ming ◽  
孙秀霞 Sun Xiuxia ◽  
刘树光 Liu Shuguang ◽  
徐嵩 Xu Song ◽  
刘希 Liu Xi
Keyword(s):  
Real Time ◽  
Focal Length ◽  
Calibration Method ◽  
Self Calibration

scholarly journals A METHOD FOR SELF-CALIBRATION IN SATELLITE WITH HIGH PRECISION OF SPACE LINEAR ARRAY CAMERA

2016 ◽  
Vol XLI-B1 ◽  
pp. 361-364
Author(s):  
Wei Liu ◽  
Fangming Qian ◽  
Yuzhe Miao ◽  
Rongjian Wang
Keyword(s):  
Real Time ◽  
Linear Array ◽  
Focal Length ◽  
Calibration Method ◽  
Geometric Parameters ◽  
Self Calibration ◽  
The Matrix ◽  
Array Camera ◽  
Ground Calibration ◽  
Matrix Array

At present, the on-orbit calibration of the geometric parameters of a space surveying camera is usually processed by data from a ground calibration field after capturing the images. The entire process is very complicated and lengthy and cannot monitor and calibrate the geometric parameters in real time. On the basis of a large number of on-orbit calibrations, we found that owing to the influence of many factors, e.g., weather, it is often difficult to capture images of the ground calibration field. Thus, regular calibration using field data cannot be ensured. This article proposes a real time self-calibration method for a space linear array camera on a satellite using the optical auto collimation principle. A collimating light source and small matrix array CCD devices are installed inside the load system of the satellite; these use the same light path as the linear array camera. We can extract the location changes of the cross marks in the matrix array CCD to determine the real-time variations in the focal length and angle parameters of the linear array camera. The on-orbit status of the camera is rapidly obtained using this method. On one hand, the camera’s change regulation can be mastered accurately and the camera’s attitude can be adjusted in a timely manner to ensure optimal photography; in contrast, self-calibration of the camera aboard the satellite can be realized quickly, which improves the efficiency and reliability of photogrammetric processing.

RECONSTRUCTING THE 3D OBJECT WITH THE RANK CONSTRAINT OF MATRIX AND ANALYZING THE DEGENERATION

2007 ◽  
Vol 04 (02) ◽  
pp. 127-140
Author(s):  
YOUFU WU ◽  
MO DAI
Keyword(s):  
Calibration Method ◽  
The Self ◽  
Experimental Results ◽  
The Other ◽  
3D Object ◽  
Intrinsic Parameters ◽  
Self Calibration ◽  
Rank Constraint ◽  
Camera Parameters ◽  
Better Than

One of the challenging problems of 3D Euclidean reconstruction is that only the hypothesis of intrinsic parameters can be used to retrieve the camera parameters. In this paper, we proposed a method to find out the intrinsic parameters of a camera using the rank constraint of the relation matrix of absolute conic Ω. Simultaneously, analyzed the degeneration of self-calibration. The experimental results showed that the self-calibration method of camera is better than the other methods.

scholarly journals A METHOD FOR SELF-CALIBRATION IN SATELLITE WITH HIGH PRECISION OF SPACE LINEAR ARRAY CAMERA

2016 ◽  
Vol XLI-B1 ◽  
pp. 361-364 ◽  
Author(s):  
Wei Liu ◽  
Fangming Qian ◽  
Yuzhe Miao ◽  
Rongjian Wang
Keyword(s):  
Real Time ◽  
Linear Array ◽  
Focal Length ◽  
Calibration Method ◽  
Geometric Parameters ◽  
Self Calibration ◽  
The Matrix ◽  
Array Camera ◽  
Ground Calibration ◽  
Matrix Array

At present, the on-orbit calibration of the geometric parameters of a space surveying camera is usually processed by data from a ground calibration field after capturing the images. The entire process is very complicated and lengthy and cannot monitor and calibrate the geometric parameters in real time. On the basis of a large number of on-orbit calibrations, we found that owing to the influence of many factors, e.g., weather, it is often difficult to capture images of the ground calibration field. Thus, regular calibration using field data cannot be ensured. This article proposes a real time self-calibration method for a space linear array camera on a satellite using the optical auto collimation principle. A collimating light source and small matrix array CCD devices are installed inside the load system of the satellite; these use the same light path as the linear array camera. We can extract the location changes of the cross marks in the matrix array CCD to determine the real-time variations in the focal length and angle parameters of the linear array camera. The on-orbit status of the camera is rapidly obtained using this method. On one hand, the camera’s change regulation can be mastered accurately and the camera’s attitude can be adjusted in a timely manner to ensure optimal photography; in contrast, self-calibration of the camera aboard the satellite can be realized quickly, which improves the efficiency and reliability of photogrammetric processing.

Sign in / Sign up

Export Citation Format

Share Document