• The Korean Journal of Applied Statistics
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• v.23 no.2
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• pp.305-315
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• 2010

In this paper, a frequentistic approach to impute the values of R, G, B-components in random missing pixels of color image is provided. Under assumption that the given image is a realization of Gaussian Markov random field, its model is designed such that each neighbor pixel values for a given pixel follows (independently) the normal distribution with covariance matrix scaled by an evaluates of the similarity between two pixel values, so that the imputation is not to be affected by the neighbors with different color. An approximate EM-based algorithm maximizing the underlying likelihood is implemented to estimate the parameters and to impute the missing pixel values. Some experiments are presented to show its effectiveness through performance comparison with a popular interpolation method.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.3
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• pp.46-54
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• 2008

Most commercial CCD/CMOS image sensors have CFA(Color Filter Array) where each pixel gathers light of a selective color to reduce the sensor size and cost. There are many algorithms proposed to reconstruct the original clolr image by adopting pettern recognition of regularization methods to name a few. However the resulting image still suffer from errors such as flase color, zipper effect. In this paper we propose an adaptive edge weight demosaicking algorithm that is based on POCS(Projection Onto Convex Sets) not only to improve the entire image's PSNR but also to reduce the edge region's errors that affect subjective image quality. As a result, the proposed algorithm reconstruct better quality images especially at the edge region.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2000.11b
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• pp.81-86
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• 2000

본 논문에서는 순차주사 CCD 이미지 센서를 위한 개선된 경계적응적 칼라 보간 구조를 제안했다. 제안된 경계 표시자(edge indicator) 함수는 채널내 상관관계뿐만 아니라 채널간의 상관관계를 이용하며 국소적으로 나타난 왜곡된 칼라는 칼라 경계 검출법에 기반한 스위칭 알고리즘에 의해 제거됐다. 개선된 경계적응적 칼라 보간 구조는 기존의 접근 방법에 비해 주관적 화질과 객관적 화질 모두 우수한 결과를 실험적으로 보였다.

• Journal of information and communication convergence engineering
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• v.6 no.3
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• pp.289-293
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• 2008

In this paper, we propose the hardware architecture to accelerate 2D Vector graphics process for mobile devices. we propose the Transformation Unit Architecture that considerates the operation dependency. It has 3 cycles excution time and uses 2 multipliers and 2 adders. Proposed paint generation unit uses a LUT method, so it does not execute color interpolation which needs to be calculated every time. The proposed OpenVG 1.0 Accelerator achieved a 2.85 times faster performance in a tiger model.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.214-216
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• 2003

아날로그 NTSC 비디오 디코더 신호를 디코딩하여 디지털화된 컬러 값을 얻기 위해서는 컬러 버스트 신호를 동기화 해야 한다. 이 버스트 신호를 이용하여 Y. I. O의 값을 분리하기 때문이다. 아날로그 디코더의 경우에는 내부에 버스트 신호와 동기화 한 클럭을 PLL이나 DLL등을 이용하여 발생시켜서 I의 위치를 알아낸다. 비디오 신호 해독을 위한 전용의 PLL을 위해 아날로그 방식의 VLSI설계를 하는 것은 많은 노력이 들어갈 뿐만 아니라 특정 Fab에 종속되어 전체 칩의 이식성을 떨어뜨리게 된다. 본 논문에서는 아날로그 PLL이 없이도 디지털 입력데이터의 산술 연산을 통해서 컬러 버스트 동기화를 검출하는 방법을 제안한다.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.78-79
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• 2003

설진(舌診)은 한의학에서 망진(望診)의 한 분야로, 환자의 설질(舌質)과 설태(舌苔)의 변화를 관찰함으로써 질병을 진찰하는 방법이다. 임상에서 설진은 의사들의 주관적인 지식과 경험에 의해서 결정되며, 광원이나 주변 환경의 밝기의 차와 같은 외부적인 요인에 의해서 영향을 받는다. 또한 진단의 결과들은 정량적으로 저장, 관리되고 있지 않다. 그러므로 설진의 조직적이고 정량적인 진단 표준을 제공하고, 객관적인 설 진단법을 구축하기 위해서 디지털화된 설진시스템의 개발이 필요하다. (중략)

• Journal of Broadcast Engineering
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• v.20 no.5
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• pp.738-747
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• 2015

It is difficult to use a recognition algorithm of an image in a foggy environment because the color and edge information is removed. One of the famous defogging algorithm is haze removal by using 'Dark Channel Prior(DCP)' which is used to predict for transmission rate using color information of an image and eliminates fog from the image. However, in case that the image has factors such as sunset or yellow dust, there is overemphasized problem on the color of certain channel after haze removal. Furthermore, in case that the image includes an object containing high RGB channel, the transmission related to this area causes a misestimated issue. In this paper, we purpose an enhanced fog elimination algorithm by using improved color normalization and haze rate revision which correct mis-estimation haze area on the basis of color information and edge information of an image. By eliminating the color distortion, we can obtain more natural clean image from the haze image.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1507-1515
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• 2021

If chlorophyll-a is estimated through ocean color remote sensing, it is able to understand the global distribution of phytoplankton and primary production. However, there are missing data in the ocean color observed from the satellites due to the clouds or weather conditions. In thisstudy, the missing data of the GOCI (Geostationary Ocean Color Imager) chlorophyll-a product wasreconstructed by using DINEOF (Data INterpolation Empirical Orthogonal Functions). DINEOF reconstructs the missing data based on spatio-temporal data, and the accuracy was cross-verified by removing a part of the GOCI chlorophyll-a image and comparing it with the reconstructed image. In the study area, the optimal EOF (Empirical Orthogonal Functions) mode for DINEOF wasin 10-13. The temporal and spatialreconstructed data reflected the increasing chlorophyll-a concentration in the afternoon, and the noise of outliers was filtered. Therefore, it is expected that DINEOF is useful to reconstruct the missing images, also it is considered that it is able to use as basic data for monitoring the ocean environment.

• Journal of IKEEE
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• v.18 no.3
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• pp.403-408
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• 2014

In this paper, we propose a rasterizer architecture using varying interpolator which process several pixels at a time. Proposed rasterizer is able to handle 16 pixel at a time and output the color of up to 64. It can reduce the redundancy of calculation by configuring a matrix transformation and matrix calculation for rasterization, and it can enhance the speed of rasterizer by increasing the reusability. As a result, proposed rasterizer has improve 11% in color interpolation, 17% in the processing speed of the rasterizer by comparing with conventional research.

• International Journal of Contents
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• v.14 no.3
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• pp.1-6
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• 2018

For 3D display applications, auto-stereoscopic display methods that can provide 3D images without glasses have been actively developed. This paper is concerned with developing a display system for elemental images of real space using integral imaging. Unlike the conventional method, which reduces a color image to the level as much as a generated depth image does, we have minimized original color image data loss by generating an enlarged depth image with interpolation methods. Our method was efficiently implemented by applying a GPU parallel processing technique with OpenCL to rapidly generate a large amount of elemental image data. We also obtained experimental results for displaying higher quality integral imaging rather than one generated by previous methods.