• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.1
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• pp.89-101
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• 2015

This paper proposes a statistical model of 3-D positions when tracking moving targets using the uncooled infrared (IR) stereo camera system. The proposed model is derived from two errors. One is the position error which is caused by the sampling pixels in the digital image. The other is the timing jitter which results from the irregular capture-timing in the infrared cameras. The capture-timing in the IR camera is measured using the jitter meter designed in this paper, and the observed jitters are statistically modeled as Gaussian distribution. This paper derives an integrated probability distribution by combining jitter error with pixel position error. The combined error is modeled as the convolution of two error distributions. To verify the proposed statistical position error model, this paper has some experiments in tracking moving objects with IR stereo camera. The 3-D positions of object are accurately measured by the trajectory scanner, and 3-D positions are also estimated by stereo matching from IR stereo camera system. According to the experiments, the positions of moving object are estimated within the statistically reliable range which is derived by convolution of two probability models of pixel position error and timing jitter respectively. It is expected that the proposed statistical model can be applied to estimate the uncertain 3-D positions of moving objects in the diverse fields.

• Proceedings of the KSPS conference
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• 2006.11a
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• pp.113-116
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• 2006

In this paper, we first implement an audio playback system for virtual reality by providing 3D audio effects to listeners. In general, such a 3D audio playback system utilizes a sound localization technique using head related transfer function (HRTF) to generate 3D audio effect. However, the 3D audio effect is degraded due to the crosstalk in the stereo loudspeaker environment. To enhance the 3D sound effect, we implement the crosstalk cancellation technique proposed by Atal and Schroeder and apply it to the 3D audio system.

• Explosives and Blasting
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• v.38 no.2
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• pp.1-12
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• 2020

Digital Image Correlation is a well-established method for displacements, strains and shape measurements of engineering objects. Stereo-camera 3D Digital Image Correlation (3D-DIC) systems have been developed to match the specific requirements for measurements posed by material and mechanical industries. Although DIC method provides the capabilities of scaling a field-of-view(FOV), dimensions of Geotechnical structure objects in many cases are too big to be measured with DIC based on a single camera pair. It can be the most important issue with applying 3D DIC to the measurement of Geotechnical structures. In this paper, We were present stereo vision conditions in a 3D DIC system that can be measured for large FOV(30×20m) and high precisions(z-displacement 0.5mm) of the ground objects with Stereo-camera DIC systems.

• Korean Journal of Remote Sensing
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• v.32 no.5
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• pp.511-527
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• 2016

We propose a rotating stereo frame camera system to acquire indoor images with a low cost. For experiments, we selected a test site and acquired images using the proposed system and control points using a total station. Using these data, we generated various indoor 3D models using commercial photogrammetric software, PhotoScan. We then performed qualitative and quantitative analysis of the generated indoor 3D models to investigate the possibility of the indoor modeling using the proposed system. From the results, it is confirmed that the generated indoor models using the proposed system can be applicable to the services not inquiring high accuracy.

• Journal of Korea Multimedia Society
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• v.15 no.6
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• pp.711-721
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• 2012

The objective of this study is to propose an efficient 3D reconstruction method for developing a stereo-vision-based haptics system which can replace "robotic eyes" and "robotic touch." The haptic rendering for 3D images requires to capture depth information and edge information of stereo images. This paper proposes the 3D reconstruction methods using LoG(Laplacian of Gaussian) algorithm and DoG(Difference of Gaussian) algorithm for edge detection in addition to the basic 3D depth extraction method for better haptic rendering. Also, some experiments are performed for evaluating the CPU time and the error rates of those methods. The experimental results lead us to conclude that the DoG method is more efficient for haptic rendering. This paper may contribute to investigate the effective methods for 3D image reconstruction such as in improving the performance of mobile patrol robots.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.1-9
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• 2014

Previous 2D-3D conversion methods to generate 3D stereo images from 2D sequence consist of labor-intensive procedures in their production pipelines. This paper presents an efficient 2D-3D conversion system based on scene structure reconstruction from image sequence. The proposed system reconstructs a scene space and produces 3D stereo images with texture re-projection. Experimental results show that the proposed method can generate precise 3D contents based on scene structure information. By using the proposed reconstruction tool, the stereographer can collaborate efficiently with workers in production pipeline for 3D contents production.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.5
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• pp.411-417
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• 2005

In this study, stereo vision system is applied to a mobile manipulator for effective tasks. The robot can recognize a target and compute the potion of the target using a stereo vision system. While a monocular vision system needs properties such as geometric shape of a target, a stereo vision system enables the robot to find the position of a target without additional information. Many algorithms have been studied and developed for an object recognition. However, most of these approaches have a disadvantage of the complexity of computations and they are inadequate for real-time visual servoing. Color information is useful for simple recognition in real-time visual servoing. This paper addresses object recognition using colors, stereo matching method to reduce its calculation time, recovery of 3D space and the visual servoing.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.4
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• pp.429-441
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• 2002

This paper concerns extracting 3D motion information from a 3D input device in real time focused to enabling effective human-computer interaction. In particular, we develop a novel algorithm for extracting 6 degrees-of-freedom motion information from a 3D input device by employing an epipolar geometry of stereo camera, color, motion, and structure information, free from requiring the aid of camera calibration object. To extract 3D motion, we first determine the epipolar geometry of stereo camera by computing the perspective projection matrix and perspective distortion matrix. We then incorporate the proposed Motion Adaptive Weighted Unmatched Pixel Count algorithm performing color transformation, unmatched pixel counting, discrete Kalman filtering, and principal component analysis. The extracted 3D motion information can be applied to controlling virtual objects or aiding the navigation device that controls the viewpoint of a user in virtual reality setting. Since the stereo vision-based 3D input device is wireless, it provides users with a means for more natural and efficient interface, thus effectively realizing a feeling of immersion.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.347-352
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• 2012

In this paper, an 2D spatial-map construction for workers identification and avoidance of AGV using the detection scheme of the spatial coordinates based on stereo camera is proposed. In the proposed system, face area of a moving person is detected from a left image among the stereo image pairs by using the YCbCr color model and its center coordinates are computed by using the centroid method and then using these data, the stereo camera embedded on the mobile robot can be controlled for tracking the moving target in real-time. Moreover, using the disparity map obtained from the left and right images captured by the tracking-controlled stereo camera system and the perspective transformation between a 3-D scene and an image plane, depth map can be detected. From some experiments on AGV driving with 240 frames of the stereo images, it is analyzed that error ratio between the calculated and measured values of the worker's width is found to be very low value of 2.19% and 1.52% on average.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.462-465
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• 2002

This paper deals with the problem of synthesis of stable and optimal grasps with unknown objects by 3-finger hand. Previous robot grasp research has analyzed mainly with either unknown objects 2D by vision sensor or unknown objects, cylindrical or hexahedral objects, 3D. Extending the previous work, in this paper we propose an algorithm to analyze grasp of unknown objects 3D by vision sensor. This is archived by two steps. The first step is to make a 3D geometrical model of unknown objects by stereo matching which is a kind of 3D computer vision technique. The second step is to find the optimal grasping points. In this step, we choose the 3-finger hand because it has the characteristic of multi-finger hand and is easy to modeling. To find the optimal grasping points, genetic algorithm is used and objective function minimizing admissible farce of finger tip applied to the object is formulated. The algorithm is verified by computer simulation by which an optimal grasping points of known objects with different angles are checked.