• Title/Summary/Keyword: Camera Lens

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An Enhanced Method for Detecting Iris from Smartphone Images in Real-Time (스마트폰 영상에서의 개선된 실시간 눈동자 검출 방법)

  • Kim, Seong-Hoon;Han, Gi-Tae
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.9
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    • pp.643-650
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    • 2013
  • In this paper, we propose a novel method for enhancing the detection speed and rate by reducing the computation in Hough Circle Transform on real-time iris detection of smartphone camera image. First of all, we find a face and eyes from input image to detect iris and normalize the iris region into fixed size to prevent variation of size for iris region according to distance from camera lens. Moreover, we carry out histogram equalization to get regular image in bright and dark illumination from smartphone and calculate minimal iris range that contains iris with the distance between corner of the left eye and corner of the right eye on the image. Subsequently, we can minimize the computation of iris detection by applying Hough Circle Transform on the range including the iris only. The experiment is carried out in two case with bright and dark illumination. Our proposed method represents that detection speed is 40% faster and detection rate is 14% better than existing methods.

A Low Cost 3D Skin Wrinkle Reconstruction System Based on Stereo Semi-Dense Matching (반 밀집 정합에 기반한 저가형 3차원 주름 데이터 복원)

  • Zhang, Qian;WhangBo, Taeg-Keun
    • Journal of Internet Computing and Services
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    • v.10 no.4
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    • pp.25-33
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    • 2009
  • In the paper, we proposed a new system to retrieve 3D wrinkle data based on stereo images. Usually, 3D reconstruction based on stereo images or video is very popular and it is the research focus, which has been applied for culture heritage, building and other scene. The target is object measurement, the scene depth calculation and 3D data obtained. There are several challenges in our research. First, it is hard to take the full information wrinkle images by cameras because of light influence, skin with non-rigid object and camera performance. We design a particular computer vision system to take winkle images with a long length camera lens. Second, it is difficult to get the dense stereo data because of the hard skin texture image segmentation and corner detection. We focus on semi-dense stereo matching algorithm for the wrinkle depth. Compared with the 3D scanner, our system is much cheaper and compared with the physical modeling based method, our system is more flexible with high performance.

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Measurement of Settling Velocity, Size and Density and Analysis of Fractal Dimension of Cohesive sediment (점착성 유사의 침강속도, 크기, 밀도 측정 플랙탈 차원 분석)

  • Son, Min-Woo
    • Korean Journal of Ecology and Environment
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    • v.44 no.1
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    • pp.58-65
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    • 2011
  • This study aims to investigate the settling velocity of aggregates of cohesive sediment (floc) and its relationship with sediment size, density and fractal dimension. A system of commercial camera and macro-lens is used for the experiment. Through the image-analysis technique, the image taken by the camera system is analyzed. For the experiment, kaolinite and a natural sediment sampled at Lake Apopka in Florida have been tested. From this study, it is known that kaolinite and Lake Apopka sediments show different behaviors mainly depending on the organic matter content. Samples of kaolinite with less organic contents show a more definite trend to follow a fractal theory and relatively strong relationships between the settling velocity, density, fractal dimension and floc size compared to the Lake Apopka sediments rich in organics.

Development of Adaptive Eye Tracking System Using Auto-Focusing Technology of Camera (눈동자 자동 추적 카메라 시스템 설계와 구현)

  • Wei, Zukuan;Liu, Xiaolong;Oh, Young-Hwan;Yook, Ju-Hye
    • Journal of Digital Contents Society
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    • v.13 no.2
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    • pp.159-167
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    • 2012
  • Eye tracking technology tracks human eyes movements to understand user's intention. This technology has been improving slowly and should be used for a variety of occasions now. For example, it enables persons with disabilities to operate a computer with their eyes. This article will show a typical implementation of an eye tracking system for persons with disabilities, after introducing the design principles and specific implementation details of an eye tracking system. The article discussed the realization of self-adapting regulation algorithm in detail. The self-adapting algorithm is based on feedback signal controlling the lens movements to realize automatic focus, and to get a clear eyes image. This CCD camera automatic focusing method has self-adapting capacity for changes of light intensity on the external environment. It also avoids the trouble of manual adjustment and improves the accuracy of the adjustment.

A Hardware Design for Realtime Correction of a Barrel Distortion Using the Nearest Pixels on a Corrected Image (보정 이미지의 최 근접 좌표를 이용한 실시간 방사 왜곡 보정 하드웨어 설계)

  • Song, Namhun;Yi, Joonhwan
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.12
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    • pp.49-60
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    • 2012
  • In this paper, we propose a hardware design for correction of barrel distortion using the nearest coordinates in the corrected image. Because it applies the nearest distance on corrected image rather than adjacent distance on distorted image, the picture quality is improved by the image whole area, solve the staircase phenomenon in the exterior area. But, because of additional arithmetic operation using design of bilinear interpolation, required arithmetic operation is increased. Look up table(LUT) structure is proposed in order to solve this, coordinate rotation digital computer(CORDIC) algorithm is applied. The results of the synthesis using Design compiler, the design of implementing all processes of the interpolation method with the hardware is higher than the previous design about the throughput, In case of the rear camera, the design of using LUT and hardware together can reduce the size than the design of implementing all processes with the hardware.

The Implementation of Video Library using VR (가상현실을 이용한 동화상 도서관의 구현)

  • 김동현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.7
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    • pp.1456-1461
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    • 2003
  • Recently, the quantity of using information go on increasing geometric-progression. At the same time, the management of information is effected on the most organization's effective operation so that many user call for the powerful equipment which expound. access more information. As information searching technology is concentrated about the object of information based on a letter mainly, an effective searching technology for the object of multimedia such as a still image, a video and a sound must be studied. As a monitor of computer is 2-D, it difficult for one to grasp the whole aspect at a look glance like a library. Accordingly, some condition is necessary. First, it acquired the virtual video, turning a camera around by 30 degrees with a camera of 15mm lens, giving a warping and distortion. Second, it improved the books for user to search easily, adding to the video in existing books information system. The original text suggests some way which can embody the video searching technology under the base of personal computer.

Object Width Measurement System Using Light Sectioning Method (광절단법을 이용한 물체 크기 측정 시스템)

  • Lee, Byeong-Ju;Kang, Hyun-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.697-705
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    • 2014
  • This paper presents a vision based object width measurement method and its application where the light sectioning method is employed. The target object for measurement is a tread, which is the most outside component of an automobile tire. The entire system applying the measurement method consists of two processes, i.e. a calibration process and a detection process. The calibration process is to identify the relationships between a camera plane and a laser plane, and to estimate a camera lens distortion parameters. As the process requires a test pattern, namely a jig, which is elaborately manufactured. In the detection process, first of all, the region that a laser light illuminates is extracted by applying an adaptive thresholding technique where the distribution of the pixel brightness is considered to decide the optimal threshold. Then, a thinning algorithm is applied to the region so that the ends and the shoulders of a tread are detected. Finally, the tread width and the shoulder width are computed using the homography and the distortion coefficients obtained by the calibration process.

Catadioptric Omnidirectional Stereo Imaging System and Reconstruction of 3-dimensional Coordinates (Catadioptric 전방향 스테레오 영상시스템 및 3차원 좌표 복원)

  • Kim, Soon-Cheol;Yi, Soo-Yeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.6
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    • pp.4108-4114
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    • 2015
  • An image acquisition by using an optical mirror is called as a catadioptric method. The catadioptric imaging method is generally used for acquisition of 360-degree all directional visual information in an image. An exemplar omnidirectional optical mirror is the bowl-shaped hyperbolic mirror. In this paper, a single camera omnidirectional stereo imaging method is studied with an additional concave lens. It is possible to obtain 3 dimensional coordinates of environmental objects from the omnidirectional stereo image by matching the stereo image having different view points. The omnidirectional stereo imaging system in this paper is cost-effective and relatively easy for correspondence matching because of consistent camera intrinsic parameters in the stereo image. The parameters of the imaging system are extracted through 3-step calibration and the performance for 3-dimensional coordinates reconstruction is verified through experiments in this paper. Measurable range of the proposed imaging system is also presented by depth-resolution analysis.

Dose Distribution of 100 MeV Proton Beams in KOMAC by using Liquid Organic Scintillator (액체 섬광체를 이용한 100 MeV 양성자 빔의 선량 분포 평가)

  • Kim, Sunghwan
    • Journal of radiological science and technology
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    • v.40 no.4
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    • pp.621-626
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    • 2017
  • In this paper, an optical dosimetric system for radiation dose measurement is developed and characterized for 100 MeV proton beams in KOMAC(Korea Multi-Purpose Accelerator Complex). The system consists of 10 wt% Ultima GoldTM liquid organic scintillator in the ethanol, a camera lens(50 mm / f1.8), and a high sensitivity CMOS(complementary metal-oxide-semiconductor) camera (ASI120MM, ZWO Co.). The FOV(field of view) of the system is designed to be 150 mm at a distance of 2 m. This system showed sufficient linearity in the range of 1~40 Gy for the 100 MeV proton beams in KOMAC. We also successfully got the percentage depth dose and the isodose curves of the 100 MeV proton beams from the captured images. Because the solvent is not a human tissue equivalent material, we can not directly measure the absorbed dose of the human body. Through this study, we have established the optical dosimetric procedure and propose a new volume dose assessment method.

A Construction of Web Application Platform for Detection and Identification of Various Diseases in Tomato Plants Using a Deep Learning Algorithm (딥러닝 알고리즘을 이용한 토마토에서 발생하는 여러가지 병해충의 탐지와 식별에 대한 웹응용 플렛폼의 구축)

  • Na, Myung Hwan;Cho, Wanhyun;Kim, SangKyoon
    • Journal of Korean Society for Quality Management
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    • v.48 no.4
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    • pp.581-596
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    • 2020
  • Purpose: purpose of this study was to propose the web application platform which can be to detect and discriminate various diseases and pest of tomato plant based on the large amount of disease image data observed in the facility or the open field. Methods: The deep learning algorithms uesed at the web applivation platform are consisted as the combining form of Faster R-CNN with the pre-trained convolution neural network (CNN) models such as SSD_mobilenet v1, Inception v2, Resnet50 and Resnet101 models. To evaluate the superiority of the newly proposed web application platform, we collected 850 images of four diseases such as Bacterial cankers, Late blight, Leaf miners, and Powdery mildew that occur the most frequent in tomato plants. Of these, 750 were used to learn the algorithm, and the remaining 100 images were used to evaluate the algorithm. Results: From the experiments, the deep learning algorithm combining Faster R-CNN with SSD_mobilnet v1, Inception v2, Resnet50, and Restnet101 showed detection accuracy of 31.0%, 87.7%, 84.4%, and 90.8% respectively. Finally, we constructed a web application platform that can detect and discriminate various tomato deseases using best deep learning algorithm. If farmers uploaded image captured by their digital cameras such as smart phone camera or DSLR (Digital Single Lens Reflex) camera, then they can receive an information for detection, identification and disease control about captured tomato disease through the proposed web application platform. Conclusion: Incheon Port needs to act actively paying.