• 한국멀티미디어학회논문지
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• 제13권3호
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• pp.410-416
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• 2010

본 논문은 광각 렌즈를 가지는 CCD 카메라에서 왜곡 보정 시 필요한 샘플화소의 좌표들을 자동으로 추출하는 알고리즘을 제안한다. 제안한 방법은 광각 렌즈를 통하여 획득한 왜곡된 영상에 대하여 노이즈를 제거한 후 에지 영상을 구한다. 그 후, 수평 방향과 수직 방향에 대한 히스토그램을 임계치와 비교하여 왜곡 좌표를 추출한다. 이 방법은 광각 CCD 카메라의 출력물에 직접 적용 할 수 있다. 그 결과 제안한 방법은 수작업으로 인한 번거로운 작업과 부정확한 샘플 좌표로 인한 오류 없이 자동으로 샘플 좌표를 추출하고 보정한 결과 영상을 얻을 수 있었다. 또한 렌즈 각과 왜곡 형태에 상관없이 적용 가능함을 확인할 수 있었다.

• 한국군사과학기술학회지
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• 제19권6호
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• pp.690-697
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• 2016

EOIS(electro-optical imaging system) is the main target of the laser weapon. Specially, the image sensor will be vulnerable because EOIS focuses the incident laser beam onto the image sensor. Accordingly, the laser-induced damage of the image sensor needs to be identified for the counter-measure against the laser attack. In this study, the laser-induced damage of the CCD image sensor irradiated by the CW(continuous wave) NIR(near infrared) laser was experimentally investigated and mechanisms of those damage occurrences were analyzed. In the experiment, the near infrared CW fiber laser was used as a laser source. As the fluence, which is the product of the irradiance and the irradiation time, increased, the permanent damages such as discoloration and breakdown appeared sequentially. The discoloration occurred when the color filter was damaged and then the breakdown occurred when the photodiode and substrate were damaged. From the experimental results, LIDTs(laser-induced damage thresholds) of damages were roughly determined.

• 한국통신학회논문지
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• 제23권9A호
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• pp.2345-2354
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• 1998

디지털 카메라의 핵심 부품인 CCD(charge couple device) 소자의 해상도는 촬영된 영상의 화질에 결정적인 요인으로 작용하며 제품 제조 원가에서도 큰 비중을 차지한다. 낮은 해상도의 소자로부터 보다 높은 해상도의 화질을 얻기 위한 많은 연구가 진행되어왔다. 본 논문에서는 에일리어싱 성분을 가우시안 저역 필터로 제거한 후, 최소 자승 스플라인보간과 경계 모델에 기반한 비선형 보간을 사용함으로써 확대된 저해상도 영상의 계단 현상, 블록화 현상등을 줄이는 동시에, 선형 보간시 나타나는 경계주변의 울림현상(ringing effect) 번짐현상(blur effect)을 최소화한다.

• Journal of Advanced Marine Engineering and Technology
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• 제23권2호
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• pp.259-269
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• 1999

A new algorithm for measuring 3-D velocity components of high speed flows were developed using a digital image processing technique. The measuring system consists of three CCD cameras an optical instrument called AOM a digital image grabber and a host computer. The images of mov-ing particles arranged spatially on a rotation plate are taken by two or three CCD cameras and are recorderd onto the image grabber or a video tape recoder. The three-dimensionl velocity com-ponents of the particles are automatically obtained by the developed algorithm In order to verify the validity of this technique three-dimensional velocity data sets obtained from a computer simu-lation of a backward facing step flow were used as test data for the algorithm. an uncertainty analysis associated with the present algorithm is systematically evaluated, The present technique is proved to be used as a tookl for the measurement of unsteady three-dimensional fluid flows.

• 한국멀티미디어학회논문지
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• 제15권3호
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• pp.291-298
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• 2012

일반적인 ATR시스템에서는 대부분 FLIR센서에 의존하여 영상을 획득하나, 표적의 경계가 모호한 경우 견실한 표적 분할을 보장할 수 없는 한계점이 있다. 이에 본 논문은 FLIR과 CCD센서를 통해 획득된 영상에 대한 적응적 가중치 기반의 융합 방법을 제안함으로써 보다 정확한 표적 분할 성능을 재현한다. 융합을 위한 FLIR영상의 가중치는 모호한 경계를 구분하기 위한 bi-modality 척도와 표적 경계와의 거리를 통해 결정되고, CCD영상의 가중치는 표적과 배경의 질감차이를 나타내는 질감 척도와 거리 척도를 통해 도출된다. 제안 방법의 타당성 검증을 위하여 다양한 환경에서 획득된 표적 영상에 대한 제안 방법과 단일 센서 기반의 표적 분할의 성능 비교를 수행하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.471-474
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• 2004

Not all CCD pixels generate uniform value for the uniform radiance due to the different process of manufacture and each pixel characteristics. And the image data compression is essential in the real time image transmission because of the high line rate and the limited RF bandwidth. This pixel's nonuniformity and the loss compression make CCD pixel correction necessary in on-orbit condition. In the MSC system, the NUC unit, which is a part of MSC PMU, is charge of the correction for CCD each pixel. The correction is performed with the gain and the offset table for the each pixel and the each TDI mode. These correction tables are generated and programmed in the PMU Flash memory through the various image data tests at the ground test. Besides, they can be uploaded from ground station after onorbit calibration. This paper describes the principle of the table generation and the test way of the non-uniformity after NUC

• 천문학회지
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• 제29권spc1호
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• pp.391-392
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• 1996

We have developed and tested a CCD camera (100 $\times$ 100 pixels) system for observing Ha images of the solar flares with time resolution> 25 msec. The 512 $\times$ 512 pixels image of CCD camera at 2 Mpixels/sec can be recorded at the rate of more than 5 frame/sec while 100 $\times$ 100 pixels area image can be obtained 40 frames/sec. The 100 $\times$ 100 pixels image of CCD camera corresponds to 130 $\times$ 130 arc - $sec^2$ of the solar disk.

• 천문학논총
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• 제11권1호
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• pp.147-161
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• 1996

The development of universal CCD camera control software for all BOAO CCD camera systems is proposed. The new software, running under Sun SPARCstation and motif based X window system with SunOS 4.1.3 operating system, replaces existing control software based on NeXTstation color and NeXTstep 2.1 operating system which is no more produced now. Several new features of the new software is introduced, some of which are 1) the image contrast is enhanced by color manipulation and display, 2) image zooming and trimming, 3) any size of image can be displayed in the scrolled window, and 4) the offset between telescope pointing position and CCD center is easily calculated by alt-azi map. Along with the above new features, the new software has advantages including ease of maintenance and upgrading and elimination of risk caused by hardware damage. Since September 1, the software beta version is being used by observers and there is not seen severe problem regarding the software itself, but several requests to equip more features to the software will be mirrored to future release.

• 한국통신학회논문지
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• 제21권6호
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• pp.1398-1415
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• 1996

Instead of using three charge-coupled devices (CCDs) for the corresponding color channels, most consumer's most consummer's color macmorders reconstruct color images by using only one CCD with a color filter array (CFA), which periodically samples different color signals. By this reson the resulting image cannot produce the full resolution of the input image. More sepecifically, a single-CCD color camcorder reconstructs red, greed, and blue color channels from a color filter array followed by a CCD. During the reconstruction process, color cross-talk among channels (interchannel distortion) and eriodically space-verying blur (intrachannel distortion) occur. The proposed restoration system reduces distortions due to interchannel interference, and then restores each color channel by removing the corresponding intrachannel distortion. Experimental results show that the proposedsystem provides the improved image in oth objective and subjective senses. A major advantage of the proposed system is feasible to real-time image improvement because it can be implemented by a finite impulse response (FIR) filter structure.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.138.2-138
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• 2001

This paper proposes the technique for recognizing the human´s emotion by using the CCD color image. To do this, we first acquire the color image from the CCD camera. And then propose the method for recognizing the expressing to be represented the structural correlation of man´s feature points(eyebrows, eye, nose, mouse), In the proposed method. Human´s emotion is divided into four emotion(surprise, anger, happiness, sadness). Finally, we have proven the effectiveness of the proposed method through the experimentation.