• Title/Summary/Keyword: Pass Image

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Topography in intertidal zone by satellite images

  • Kang, Yong-Q.
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.664-669
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    • 2002
  • Intertidal zone (tidal flat) is a place which is sometimes dry and sometimes wet depending on the tidal rhythm. Direct measurement of topography in the intertidal zone is very difficult to be achieved. The interface between wet and dry parts in the tidal flat, which can be identified from near infrared band of satellite image, is a 'depth contour' which corresponds to the sea level at the time of satellite pass. Aquisition of topography data in tidal flat is possible by combining various techniques such as (1) identification of the interface between wet and dry parts, (2) GCP correction of satellite image, and (3) realtime prediction of sea level elevation at the time of satellite pass. The algorithm was successfully applied in obtaining topography (bathymetry) data in the intertidal zone of Asan Bay in the west coast of Korea from 26 satellite images. The method is expected to be very efficient in making bathymetry data base in the western and southern parts of Korea where tidal flats are well developed in wide regions.

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An Experimental Study on Chemiluminescence Characteristics of a Turbulent Flame (난류화염의 화학적 발광 특성에 관한 실험적 연구)

  • Kwon, Minjun;Kim, Sewon;Lee, Changyeop;Kim, Yongmo
    • Journal of the Korean Society of Combustion
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    • v.20 no.4
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    • pp.1-9
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    • 2015
  • The object of this study is a deriving the relations according to the measuring locations between the chemiluminescence and the flame state at commercial burner. In this study, the flame chemiluminescence of the flame of commercial burner is measured using a photomultiplier tube and the optical band-pass filter. In addition, the contour of the chemiluminescence of the flame is measured using the common CCD camera and the optical band-pass filters, and the acquired images is converted by the simple image processing as a matrix form. The results showed that certain relationship between optical data and equivalence ratio exists, and the contour according to the measuring location of the flame chemiluminescence is different by equivalence ratio.

Object Based Image Compression Using QP (Quadratic Programming) Method (QP(Quadratic Programming) 방법을 이용한 객체단위의 영상압축 알고리즘)

  • 최유태;이상엽;곽대호;김시내;송문호
    • Proceedings of the IEEK Conference
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    • 2000.11d
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    • pp.175-178
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    • 2000
  • The object level image compression is a useful technology for reducing the necessary data and manipulating individual objects. In this paper, we propose a new image object compression algorithm that uses the quadratic programming (QP) method to reduce the compressed data. The results indicate the superiority of the proposed QP based algorithm over the low pass extrapolation (LPE) method of MPEG-4.

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A Study on the Comparison for Shape Interpolation of Magnified Image (확대 영상의 보간에 관한 비교 연구)

  • Lee, Y.J.;Lee, H.W.;Lee, H.A.
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3165-3168
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    • 1999
  • When a input image is extensively magnified on the computer system, it is almost impossible to replicate the original shape because of mismatched coordinates system. In order to resolve the problem, the shape of the magnified image has been reconfigured using the bilinear interpolation method, low pass special filtering interpolation method and B-spline interpolation method. Ferguson curve interpolation method based on the CAD/CAM curve interpolation algorithm.

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Gray-level Image Watermarking using Wavelet Transform (웨이브렛 변환을 이용한 그레이-레벨 영상 워터마킹)

  • Min, Sun-Jin;Chung, Hoon;Kim, Chung-Hwa
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.487-490
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    • 2001
  • With the establishment of the optimized copyright, digital image watermarking technique is demended to identify the owner of a certain image and to avoid the unauthorized distribution of digital image copies. Also, a robust watermarking approach should survive several possible attacks, such as image processing and lossy image compession. The proposed scheme distributes the 256 gray-level signature information in discrete wavelet transform domain of the host image where is very little visible distortion. While much of the privious work used signature data that is a small fraction of th e host images the proposed approach can easily handle gray-scale Images. As the result, stable reconstruction can be obtained even when the images are transformed, JPEG lossy compression or otherwise modified by low-pass filtering operations.

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Comparative Analysis of LPF and HPF for Roads Edge Detection from High Resolution Satellite Imagery (고해상도위성영상에서 도로 경계 검출을 위한 고주파와 저주파 필터링 비교분석에 관한 연구)

  • Choi, Hyun;Kang, In-Joon
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.3 s.37
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    • pp.3-11
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    • 2006
  • The need for edge detection about topography data from the high resolution satellite imagery is happening with increasing frequency according to many people utilize the its imagery as various fields recently. Many experts is recognizing of other GIS will make use of the road detection from the high resolution satellite imagery, including ITS (Intelligent Transportation Systems) and urban planning. This paper is comparative analysis of LPF (Low Pass Filtering) and HPF (High Pass Filtering) for roads edge detection from high resolution satellite imagery. As a result, LPF and HPF can be highlight selective pixels at edge area about input data. In case or applying to other techniques such as LPF for the same purpose, they aye more effective for wide road width which often cause the slight distortion of boundary or overall change of brightness values on the whole Image. Whereas, HPF has ability to enhance selectively detailed components in a target image.

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Fast Frame Selection Method for Multi-Reference and Variable Block Motion Estimation (다중참조 및 가변블록 움직임 추정을 위한 고속 참조영상 선택 방법)

  • Kim, Sung-Dae;SunWoo, Myung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.6
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    • pp.1-8
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    • 2008
  • This paper introduces three efficient frame selection schemes to reduce the computation complexity for the multi-reference and variable block size Motion Estimation (ME). The proposed RSP (Reference Selection Pass) scheme can minimize the overhead of frame selection. The MFS (Modified Frame Selection) scheme can reduce the number of search points about 18% compared with existing schemes considering the motion of image during the reference frame selection process. In addition, the TPRFS (Two Pass Reference frame Selection) scheme can minimize the frame selection operation for the variable block size ME in H.264/AVC using the character of selected reference frame according to the block size. The simulation results show the proposed schemes can save up to 50% of the ME computation without degradation of image Qualify. Because the proposed schemes can be separated from the block matching process, they can be used with any existing single reference fast search algorithms.

Noise Reduction Method in consideration of bandwidth of Low Pass Filter (저역통과 필터의 대역폭을 고려한 잡음 제거 방법)

  • Yang, Jeong-Ju;Jang, Won-Woo;Kwak, Boo-Dong;Kang, Bong-Soon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.157-159
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    • 2010
  • Most digital cameras apply a Charge Coupled Device(CCD) Sensor or a Complementary Metal Oxide Semiconductor(COMS) Sensor. And the images captured these sensors include unwanted noises. In this paper, we proposed a method of the Noise Reduction(NR) about noise reduction or recovery in the image. The proposed NR method is related to Bandwidth of the Low Pass Filter(LPF). For improvement of NR, we were changing the filter coefficient of the LPF. The results of simulations with various filter coefficients, [1 2 1] in the LPF and [-1 2 -1] in the High Pass Filter(HPF) have ideal frequency bandwidth and high performance. We proposed a filter coefficient [1 2 1] and [-1 2 -1] in the LPF and the HPF respectively.

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Image Processing Using Multiplierless Binomial QMF-Wavelet Filters (곱셈기가 없는 이진수 QMF-웨이브렛 필터를 사용한 영상처리)

  • 신종홍;지인호
    • Journal of Broadcast Engineering
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    • v.4 no.2
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    • pp.144-154
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    • 1999
  • The binomial sequences are family of orthogonal sequences that can be generated with remarkable simplicity-no multiplications are necessary. This paper introduces a class of non-recursive multidimensional filters for frequency-selective image processing without multiplication operations. The magnitude responses are narrow-band. approximately gaussian-shaped with center frequencies which can be positioned to yield low-pass. band-pass. or high-pass filtering. Algorithms for the efficient implementation of these filters in software or in hardware are described. Also. we show that the binomial QMFs are the maximally flat magnitude square Perfect Reconstruction paraunitary filters with good compression capability and these are shown to be wavelet filters as well. In wavelet transform the original image is decomposed at different scales using a pyramidal algorithm architecture. The decomposition is along the vertical and horizontal direction and maintains constant the number of pixels required to describe the images. An efficient perfect reconstruction binomial QMF-Wavelet signal decomposition structure is proposed. The technique provides a set of filter solutions with very good amplitude responses and band split. The proposed binomial QMF-filter structure is efficient, simple to implement on VLSl. and suitable for multi-resolution signal decomposition and coding applications.

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