• Title/Summary/Keyword: Camera Lens

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Estimation of Disparity for Depth Extraction in Monochrome CMOS Image Sensors with Offset Pixel Apertures (깊이 정보 추출을 위한 오프셋 화소 조리개가 적용된 단색 CMOS 이미지 센서의 디스패리티 추정)

  • Lee, Jimin;Kim, Sang-Hwan;Kwen, Hyeunwoo;Chang, Seunghyuk;Park, JongHo;Lee, Sang-Jin;Shin, Jang-Kyoo
    • Journal of Sensor Science and Technology
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    • v.29 no.2
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    • pp.123-127
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    • 2020
  • In this paper, the estimation of the disparity for depth extraction in monochrome complementary metal-oxide-semiconductor (CMOS) image sensors with offset pixel apertures is presented. To obtain the depth information, the disparity information between two different channel data of the offset pixel apertures is required. The disparity is caused by the difference in the response angle between the left- and right-offset pixel aperture images. A depth map is implemented by the generated disparity. Therefore, the disparity is the most important factor for realizing 3D images from the designed CMOS image sensor with offset pixel apertures. The disparity is influenced by the pixel height and offset value of the offset pixel aperture. To confirm this correlation, the offset value is set to maximum within the pixel area, and the disparity values corresponding to the difference in the heights are calculated and compared. The disparity is derived using the camera-lens formula. Two monochrome CMOS image sensors with offset pixel apertures are used in the disparity estimation.

Extraction of Subject Size in Still Image Using Floor Pattern (바닥 패턴을 이용한 단일영상 내의 피사체 크기 추출)

  • Hwang, Min-Gu;Kim, Dong-Min;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
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    • v.11 no.4
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    • pp.11-17
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    • 2011
  • This paper aims to realize the information of a subject existing in a still image with objective values. To attain the goal, this research takes the vanishing point that a 2D still image has as the basis and recomposes the still image into a 3D image using a 3D program. Also, in order to set up the axis of the camera necessary to recompose a 3D image, this paper used the lens angle of view that the image has and floor patterns as well. The 3D image completed in this way can measure the size and distance of all subjects in the floor patterns if the size value of a particular reference subject is known, and through this, it can be possible to acquire basic information of a subject that can be either a criminal or a clue in the images of CCTVs or some criminal scene.

Synchrotron Radiation Imaging of Tissues Using Phase Contrast Technique (방사광 위상차 현미경을 이용한 생체조직의 미세구조 영상)

  • Kang, Bo-Sun;Lee, Dong-Yeol;Kim, Ki-Hong
    • Journal of the Korean Society of Radiology
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    • v.2 no.2
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    • pp.23-30
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    • 2008
  • X-ray microscopy with synchrotron radiation(SR) might be a useful tool for novel x-ray imaging in the clinical and laboratory settings. Microscopically, it enables us to observe detailed structure of animal organs samples with a great magnification power and an excellent resolution. The phase contrast mechanisms in image by X-ray are described. The phase-contrast X-ray imaging with SR from in-vivo and in-vitro mouse tail, rat nerve and rat lung were obtained with an 8 KeV monochromatic beam. The visual image was magnified using 10x microscope objective lens and captured using an digital CCD camera. The results showed more structural details and high resolution images with SR imaging system than conventional X-ray radiography system. The SR imaging system may have a potential for imaging in biological researches, material applications and clinical radiography.

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Analysis of Coen Brothers's Directing Style: Centering around Crime Movies (코엔 형제의 연출 스타일 분석 :범죄 영화를 중심으로)

  • Lee, Jeong-Gook
    • The Journal of the Korea Contents Association
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    • v.10 no.6
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    • pp.236-248
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    • 2010
  • Through this thesis, I analyzed Coen brothers's directing style centering around Crime movies: Blood simple, Barton Fink, Fargo, The man who wasn't thers, No country for old man. About directing style of Coen brothers, plot is an epic depiction, habitual use of narration, refusal of happy ending. They concern subject matters about human original nature and tragedy by greed. And as motifs, they often use misunderstanding, crossing over, chase. Also they likes characters of ordinary people who is destroyed by greed. How about their technical style? They usually use steady-cam and wide lens in camera, and in his early crime movies he used expressionistic lights, but after that they usually used realistic natural lights. About sound, they likes more sound effects than music. Also they directed realistic acting and emphasized actor's personality. Coen brothers has been directed many crime movies and comedy films. But their unique directing style was particularly outstanding in the crime movies

Comparative Performance Evaluations of Eye Detection algorithm (눈 검출 알고리즘에 대한 성능 비교 연구)

  • Gwon, Su-Yeong;Cho, Chul-Woo;Lee, Won-Oh;Lee, Hyeon-Chang;Park, Kang-Ryoung;Lee, Hee-Kyung;Cha, Ji-Hun
    • Journal of Korea Multimedia Society
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    • v.15 no.6
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    • pp.722-730
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    • 2012
  • Recently, eye image information has been widely used for iris recognition or gaze detection in biometrics or human computer interaction. According as long distance camera-based system is increasing for user's convenience, the noises such as eyebrow, forehead and skin areas which can degrade the accuracy of eye detection are included in the captured image. And fast processing speed is also required in this system in addition to the high accuracy of eye detection. So, we compared the most widely used algorithms for eye detection such as AdaBoost eye detection algorithm, adaptive template matching+AdaBoost algorithm, CAMShift+AdaBoost algorithm and rapid eye detection method. And these methods were compared with images including light changes, naive eye and the cases wearing contact lens or eyeglasses in terms of accuracy and processing speed.

Real-time Gaussian Hole-Filling Algorithm using Reverse-Depth Image (반전된 Depth 영상을 이용한 실시간 Gaussian Hole-Filling Algorithm)

  • Ahn, Yang-Keun;Hong, Ji-Man
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.7
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    • pp.53-65
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    • 2012
  • Existing method of creating Stereoscopy image, creates viewpoint image from the left and right by shooting one object with 2 lens in certain distance. However, in case of 3-D TV using Stereoscopy camera, the necessity to transmit 2 viewpoint images from the left and right simultaneously, increases the amount of bandwidth. Various and more effective alternatives are under discussion. Among the alternatives, DIBR(Depth Image Based Rendering) creates viewpoint images from the left and right using one image and its Depth information, thus decreasing the amount of transmitted bandwidth. For this reason, there have been various studies on Algorithm to create DIBR Image in existing Static Scene. In this paper, I would like to suggest Gaussian Hole-filling solution, which utilizes reverse-depth image to fill the hole naturally, while minimizing distortion of background. In addition, we have analyzed the effectiveness of each Algorithm by comparing and calculating its functions.

Safety Evaluation of the Lighting at the Entrance of a Very Long Road Tunnel: A Case Study in Ilam

  • Mehri, Ahmad;Hajizadeh, Roohalah;Dehghan, Somayeh Farhang;Nassiri, Parvin;Jafari, Sayed Mohammad;Taheri, Fereshteh;Zakerian, Seyed Abolfazl
    • Safety and Health at Work
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    • v.8 no.2
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    • pp.151-155
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    • 2017
  • Background: At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. Methods: The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, 35-mm single-lens reflex; Yashica, Nagano, Japan) was used to take photographs of the safe stopping distance from the tunnel entrance. Equivalent luminance was determined according to the Holliday polar diagram. Results: Considering the average luminance at the tunnel entrance ($116.7cd/m^2$) and using Adrian's equation, the safe level of lighting at the entrance of the tunnel was determined to be 0.7. Conclusion: A comparison between the results of the safe levels of lighting at the entrance of the tunnel and the De Boer scale showed that the phenomenon of black holes is created at the tunnel entrance. This may lead to a misadaptation of the drivers' eyes to the change in luminance level at the entrance of the tunnel, thereby increasing the risk of road accidents in this zone.

Development of Defects Detecting System for Corrugated Board, Mill Application, and Changes of Production Defects Ratio (골판지 불량 검색 시스템 개발, 현장적용과 생산 불량률 변화)

  • Jeong, Jin-Mo;Min, Kyung-Eun;Kim, Mun-Sung;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.2
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    • pp.37-42
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    • 2008
  • Defects of corrugated board were limiting factors to the corrugated industry's growth. On-line detecting systems of defects are beneficial to increase profits of the corrugated board companies by reducing base paper consumption, increasing process reliability, and increasing productivity. By replacing naked eye inspection of defects to a defects detecting system, continuous inspection without fatigue may guarantee final products quality. The system was developed, which was consisted of line scan CCD camera, lens, illuminating parts, high speed image processor, software, various input parts, and output parts. First installation location of the system was at before fluting process after base paper unwinding, and surface of liner board was inspected by the system. Second installation location was after fluting process and combining process for liner board. Production loss includes ragged appearance of edge, irregular flute shape, wrong combination of flute, score cracking, defects in base paper, and flute cracking. The production loss was analyzed before and after the system installation at a commercial domestic mill. The production loss ratio was defined as a production loss weight per total production weight. The production loss ratio before the installation was decreased a lot from 1.28%(during 3 months before installation) to 0.76%(during 12 months after the first installation) and to 0.25%(during 6 months after the second installation).

An Intelligent Decision Support System for Retinal Disease Diagnosis based on SVM using a Smartphone (스마트폰을 이용한 SVM 기반 망막 질병 진단을 위한 지능적인 의사 결정 지원 시스템)

  • Lee, Byung-Kwan;Jeong, Eun-Hee;Tifani, Yusrina
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.8 no.5
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    • pp.373-383
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    • 2015
  • This paper proposes a decision support system to recognizing retinal diseases. This paper uses a smartphone platform and cloud computing as the base of the system. A microscopic lens is attached int' the smartphone camera to capture the user retinal image for recognizing the user's retinal condition. An application is assembled in computer and then installed in to the smartphone. The application role is to connect between the system in smartphone and system in cloud, the application will send the retinal image to the cloud system to be classified. The paper uses OCFE (optimized classifier based on feature elimination) algorithm as the classifier. The retinal image is trained using combination of two ophthalmology databases DIARETDB1 v2.1 and STARE. Therefore, this system average accuracy is 88%, while the average error rate is 12%.

Study on the Pattern of Internal Flow inside a water droplet placed on Vibrating Hydrophobic Surface (진동하는 소수성 표면 위에 놓인 액적의 모드별 내부유동 패턴변화에 관한 연구)

  • Kim, Hun;Shin, Young Sub;Lim, Hee Chang
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.4
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    • pp.329-335
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    • 2014
  • This study aimed to understand the internal flow characteristics of a liquid droplet subject to periodic forced vibration. In order to predict the resonance frequency of a droplet, a high-speed camera and macro lens were used to capture internal flow characteristics of a droplet placed on a vibrating hydrophobic surface. Results showed that the droplet assumed a variety of shapes depending on the resonance mode of free droplet, particularly in modes 2, 4, 6, and 8. In addition, the induced internal vortex flow inside the droplet was also observed in each mode. Typically, the induced flow moved upwards along the axis of symmetry and downwards along the surface of the droplet, that is, from the apex to the contact line in modes 2 and 4, after which it broke into a smaller vortex. On the other hand, the large-scale vortex always remained steady in modes 6 and 8. The speed of the flow in mode 4 was always greater than that in mode 2, but those in modes 6 and 8 were similar.