• 제목/요약/키워드: Low-contrast Image

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일반화 대칭변환을 변형한 관심 연산자에 의한 사전 정보없는 다중 물체 분할 (Context-free multiple-object segmentation using attention operator based on modified generalized symmetry transform)

  • 구태모;전준형;최흥문
    • 전자공학회논문지C
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    • 제34C권4호
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    • pp.36-44
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    • 1997
  • An efficient context-free multiple-object segmentation using attention operator based on modified generalized symmetry transform is proposed and implemented by modifying a radial basis function network. By using the difference of intensity gradient, instead of te intensity gradient itself, in generalized symmetry tranform so as to make the attention operator to preserve the edges of the objects shape, an efficient context-free multiple-object segementation is proposed in which no a priori shape informtion on the objects is requried. The attention operator is implemented by using a modified radial basis function network which can reflect symmetry, and by using te edge pyramid of the input image, both of the local and the global symmetry of the objects are reflected simultaneously to make the multiple-object with different sizes be segmented with a singel fixed-size $n\timesm$ can be done with O(n) complexity. The simulaton results show that the proposed algorithm can efficiently be used in context-free multiple-object segmentation even for the low contrast IR images as well as for the images from the camera.

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두개의 수평 배향된 액정층을 이용한 비틀린 네마틱 액정 셀의 시야각 화질 조절 (Control of Off-axis Viewing Quality using Two Additional Homogeneous LC Layers in Twisted Nematic mode)

  • 최민오;임영진;정은;이승희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.53-54
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    • 2006
  • We have studied the viewing angle control of a twist nematic liquid crystal display (TN-LCD). The TN-LCD exhibits a bad image quality along vertical direction, due to characteristics such as low contrast ratio and grey scale inversion. The proposed new TN-LCD has the function of switching between the wide viewing mode and narrow viewing angle mode using two tilted LC layers at both sides of a TN-cell Tilt angles of the two LC layers, $14^{\circ}$ and $60^{\circ}$ were required in both wide viewing angle and narrow viewing angle modes, respectively.

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A Study on the Color Performance of FFS Mode Using the Various Analysis Methods

  • Park, Se-Hong;Park, Eun-Jung;Han, Sang-Hun;Park, Jong-Gyun;Park, In-Cheol;Lee, Kyung-Ha;Lee, Jung-Yeal
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.691-694
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    • 2006
  • So far, we have done much research improving quality of LCD TV. Recently, we have developed 26" WXGA LCD TV by advance fringe field switching (AFFS) technology with smooth and every scene realistic in color image that obtained from the amazing authentic color delivery, optical characteristic and fast response time. Our upgrade device has shown the brightness over 600nits (Color shift <0.015 and Transmittance ratio > 5.5%), gray to gray response time under 6ms, contrast ratio over 1200:1 and viewing angle over 178/178, respectively. And also, motion artifacts improved by fast response of LC with low viscosity, cell gap and dielectric constant.

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광회전 커널 오퍼레이션을 이용하는 방향성 정보 처리 (Directional Information Processing Using Optical Rotating Kernel Operations)

  • Yim Kul Lee
    • 전자공학회논문지B
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    • 제30B권2호
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    • pp.78-86
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    • 1993
  • A nonlinear method for directional information processing is introduced, along with an application of directional feature enhancement. In this method, an input is convolved with a 2-D ong, norrow kernel, which is rotated through 360 degree, continuously or discretely in a large number of steps. An output is given by some function of the convolution results. Linear features that are aligned with the kernel are enhanced, otherwise, removed or suppressed. The method presented is insensitive to variation in the dimension of linear features to be processed and preserves a good enhancement capability even for an image characterized by low contrast and spatially varying brightness in noisy backgroung. Effects of the kernel legnth and width on the performance are discussed. A possible hybrid optical-electronic implementation is also discussed.

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3T DWIs with Different b-Values in Brain Tumors

  • 김대진;장기현;송인찬;권배주;한문희
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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    • pp.24-24
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    • 2003
  • Purpose: It is known that diffusion-weighted MR imaging (DWI) is helpful in the evaluation of malignancy grading in brain tumor. This study was to evaluate the DWls with different b-values of various brain tumors in order to determine optimal b-values on 3T MR unit. Method: On a 3T MR unit, DWls with b-values of 1, 000, 3, 000 and 5, 000 s/mm2 were obtained in 20 patients of pathologically-proven brain tumors (7 metastases, 4 high grade gliomas, 2 Iymphomas, 2 low grade gliomas, 2 germinomas, and one each of germinoma, meningioma, hemangioblastoma and central neurocytoma. The overall image quality, contrast between normal brain parenchyma and tumor and signal intensities of solid and cystic components were comparatively evaluated among DWls with different b-values by visual inspection.

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REAL-TIME DETECTION OF MOVING OBJECTS IN A ROTATING AND ZOOMING CAMERA

  • Li, Ying-Bo;Cho, Won-Ho;Hong, Ki-Sang
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.71-75
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    • 2009
  • In this paper, we present a real-time method to detect moving objects in a rotating and zooming camera. It is useful for camera surveillance of fixed but rotating camera, camera on moving car, and so on. We first compensate the global motion, and then exploit the displaced frame difference (DFD) to find the block-wise boundary. For robust detection, we propose a kind of image to combine the detections from consecutive frames. We use the block-wise detection to achieve the real-time speed, except the pixel-wise DFD. In addition, a fast block-matching algorithm is proposed to obtain local motions and then global affine motion. In the experimental results, we demonstrate that our proposed algorithm can handle the real-time detection of common object, small object, multiple objects, the objects in low-contrast environment, and the object in zooming camera.

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Disaster and Safety Map Services Using Real Time Big Data Analysis

  • Lim, Jongtae;Kim, Yeonwoo;Kim, Byounghoon;Ko, Geonsik;Choi, Minwoong;Kim, Gihoon;Yoo, Seunghun;Song, Heesub;Bok, Kyoungsoo;Hayashida, Yukuo;Yoo, Jaesoo
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2016년도 춘계 종합학술대회 논문집
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    • pp.257-258
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    • 2016
  • In my paper, an evaluation method on naturalness and urbanness characterizations of animation image is proposed. In contrast to the prior works, we intend to give the exact degree of naturalness and urbanness by combining the low-level visual feature-based schemes with the biological visual schemes. In our method, four descriptors are extracted and pseudoinverse is adopted. By this method, we can experiment on the exact degree of naturalness and urbanness with satisfactory results.

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신국부 적응 에지 연산자에 관한 연구 (A Study on a New Locally Adaptive Edge Operator)

  • 정규성;박래홍
    • 대한전자공학회논문지
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    • 제24권5호
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    • pp.841-848
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    • 1987
  • This paper presents a new two-stage edge detection algorithm which can give thin edges and can find edges between low contrast regions. In the first stage, the potential edge points are obtained using the proposed edge operator which is motivated by the concept of the E filter. And in the second stage, the real edge points adre detected by comparing the potential edge values with the lically adaptive threshold values of the corresponding potential edge points and by testing whether the potential edge points are zero-crossing points or not. It is shown quantitatively that the proposed algorithm can find edges effectively in an image with impulse noise, and also the results of applying the proposed algorithm to real images are presented.

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두 액정 층의 광학적 보상을 이용한 비틀린 네마틱 액정 셀의 시야각 조절 (Viewing angle control of TN-LCD using optical compensation of two LC layers)

  • 최민오;임영진;정은;이승희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.479-480
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    • 2006
  • We have studied the viewing angle control of a twist nematic liquid crystal display (TN-LCD). The TN-LCD exhibits a bad image quality along vertical direction, due to characteristics such as low contrast ratio and gray scale inversion. The proposed new TN-LCD has the function of switching between the wide viewing mode and narrow viewing angle mode using two tilted LC layers at both sides of a TN-cell. Tilt angles of the two LC layers, $14^{\circ}$ and $60^{\circ}$ were required in both wide viewing angle and narrow viewing angle modes, respectively.

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A Method of Combining Scrambling Technology with Error Control Coding to Realize Both Confidentiality and Reliability in Wireless M2M Communication

  • Zhang, Meng;Wang, Zhe;Guo, Menghan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제6권1호
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    • pp.162-177
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    • 2012
  • In this paper we present a novel method of applying image scrambling technology which belongs to the information hiding field in the error control coding to introduce confidentiality in wireless machine to machine communication. The interleaver in serial concatenated convolutional codes, which is the key module in overcoming burst errors, is deliberately designed with the scrambling function to provide a low error rate for those authorized transceivers. By contrast, the unauthorized transceivers without keys would get so high an error rate that decoding bits could bring little value, thus realizing both the confidentiality and reliability in wireless machine to machine communication.