• Journal of Multimedia Information System
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• 제5권1호
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• pp.9-14
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• 2018

A road recognition system or Lane departure warning system is an early stage technology that has been commercialized as early as 10 years but can be optional and used as an expensive premium vehicle, with a very small number of users. Since the system installed on a vehicle should not be error prone and operate reliably, the introduction of robust feature extraction and tracking techniques requires the development of algorithms that can provide reliable information. In this paper, we investigate and analyze various real-time road detection algorithms based on color information. Through these analyses, we would like to suggest the algorithms that are actually applicable.

• 한국인쇄학회지
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• 제18권2호
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• pp.55-68
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• 2000

Joint photographic experts group (JPEG) is a standard still-image compression technique, established by the international organization for standardization (ISO) and international telecommunication standardization sector (ITUT). The standard is intended to be utilized in the various kinds of color still imaging systems as a standard color image coding format. Because JPEG is a lossy compression, the decompressed image pixel values are not the same as the value before compression. Various distortions of JPEG compression and JPEG recompression has been reported in various papers. The Image compressed by JPEG is often recompressed by same type compression method in JPEG. In general, JPEG is a lossy compression and the quality of compressed image is predicted that is varied in according to recompression Q-factor. In this paper, four difference color samples(photo image, gradient image, gradient image, vector drawing image, text image) were compressed in according to various Q-factor, and then the compressed images were recompressed according to various Q-factor once again. As the result, this paper evaluate the variation of image quality and file size in JPEG recompression and recommed the optimum recompression factor.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 추계학술발표대회
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• pp.1118-1121
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• 2010

With the advent of cell phone digital cameras, and sophisticated photo editing software, digital images can be easily manipulated and altered. Although good forgeries may leave no visual clues of having been tampered with, they may, nevertheless, alter the underlying statistics of an image. Most digital camera equipped in cell phones employ a single image sensor in conjunction with a color filter array (CFA), and then interpolates the missing color samples to obtain a three channel color image. This interpolation introduces specific correlations which are likely to be destroyed when tampering with an image. We quantify the specific correlations introduced by CFA interpolation, and describe how these correlations, or lack thereof, can be automatically detected in any portion of an image. We show the efficacy of this approach in revealing traces of digital tampering in lossless and lossy compressed color images interpolated with several different CFA algorithms in test cell phones.

• 대한의용생체공학회:의공학회지
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• 제35권1호
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• pp.1-7
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• 2014

Among semi-quantitative or fully quantitative lateral flow assay readers, an image sensor-based instrument has been widely used because of its simple setup, cheap sensor price, and compact equipment size. For all previous approaches, monochrome CCD or CMOS cameras were used for lateral flow assay imaging in which the overall intensities of all colors were taken into consideration to estimate the analyte content, although the analyte related color information is only limited to a narrow wavelength range. In the present work, we introduced a color CCD camera as a sensor and a color decomposition method to improve the sensitivity of the quantitative biosensor system which utilizes the lateral flow assay successfully. The proposed setup and image processing method were applied to achieve the quantification of imitatively dispensed particles on the surface of a porous membrane first, and the measurement result was then compared with that using a monochrome CCD. The compensation method was proposed in different illumination conditions. Eventually, the color decomposition method was introduced to the commercially available lateral flow immunochromatographic assay for the diagnosis of myocardial infarction. The measurement sensitivity utilizing the color image sensor is significantly improved since the slopes of the linear curve fit are enhanced from 0.0026 to 0.0040 and from 0.0802 to 0.1141 for myoglobin and creatine kinase (CK)-MB detection, respectively.

• 한국해양공학회지
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• 제34권6호
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• pp.442-453
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• 2020

Underwater color images suffer from low visibility and color cast effects caused by light attenuation by water and floating particles. This study applied single image enhancement techniques to enhance the quality of underwater images and compared their performance with real underwater images taken in Korean waters. Dark channel prior (DCP), gradient transform, image fusion, and generative adversarial networks (GAN), such as cycleGAN and underwater GAN (UGAN), were considered for single image enhancement. Their performance was evaluated in terms of underwater image quality measure, underwater color image quality evaluation, gray-world assumption, and blur metric. The DCP saturated the underwater images to a specific greenish or bluish color tone and reduced the brightness of the background signal. The gradient transform method with two transmission maps were sensitive to the light source and highlighted the region exposed to light. Although image fusion enabled reasonable color correction, the object details were lost due to the last fusion step. CycleGAN corrected overall color tone relatively well but generated artifacts in the background. UGAN showed good visual quality and obtained the highest scores against all figures of merit (FOMs) by compensating for the colors and visibility compared to the other single enhancement methods.

• 한국수산과학회지
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• 제42권2호
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• pp.171-178
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• 2009

The purpose of this study was the development of a digital water color measurement system using a CCD optical device. Photographs of the standard medium of Forel and Ule water color scales in the laboratory, and one of sea surface above a Secchi disc (Z=SD/2) immersed in seawater were taken. The colors of these pictures were estimated with the value of CIE $L^*a^*b^*$. Water color assessment was conducted with a digital photo-image. In the case of the Forel scale (No. 1-11), the $b^*$ value was so high that the water color number was large. In the Ule scale (No.11-21), the $a^*$ value became high, which is why the number on the water color scale was large. The color of these pictures showed that the $a^*$ value in the Forel scale and the $b^*$ value in the Ule scale increase with the increase of the F value. The $a^*$ value of seawater color was always lower than the one on the Forel and Ule water color scales. This indicates that the color of the scales differs from actual seawater color. It was concluded that water color number can more effectively be assessed by estimating the ${\Delta}Eab^*$ color difference between the water scales and actual seawater color.

• 한국산업보건학회지
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• 제25권4호
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• pp.465-471
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• 2015

Objectives: An objective of this study is to apply a thermal image camera which shows various color according to temperature of indoor surface for estimating concentration of airborne fungi. Materials and Methods: While wall temperature were monitored by applying the thermal image camera, airborne bacteria as well as air temperature and relative humidity have been measured in lecture room and toilet of university for seven months. Results: Based on the results obtained from this study, the ranges of temperature and airborne fungi concentration were $20{\sim}24^{\circ}C$ and $20{\sim}400cfu/m^3 $ for red image, $17.5{\sim}20^{\circ}C$ and $35{\sim}150cfu/m^3$ for orange image, $15.5{\sim}17.5^{\circ}C$ and $25{\sim}650cfu/m^3$ for sky-blue image, and $13.5{\sim}15.5^{\circ}C$ and $50{\sim}200cfu/m^3$ for blue image, respectively. The color of indoor surface taken shot by thermal image camera showed consistent trend with temperature of indoor surface. There is, however, little correlation between color of indoor surface and airborne fungi concentration(p>0.05). Among environmental factors, relative humidity in indoor air showed a significant relationship with airborne fungi concentration(p<0.05). Conclusions: The more measurement data for proving statistically an association between color of indoor surface and airborne fungi concentration should be provided to easily estimate indoor level of airborne fungi.

• 한국인터넷방송통신학회논문지
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• 제14권3호
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• pp.155-162
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• 2014

본 논문에서는 이동차량 양상 안정화를 위한 효율적인 흔들림 보정 기법을 제안한다. 제안된 흔들림 보정 기법은 입력으로 받은 영상 이미지 프레임의 색상 분리를 통한 변환 및 분리정보에 대한 누적 히스토그램을 계산하였고, 흔들리는 차량용 영상 이미지를 보정한 결과에서 색상 정보를 맞추기 위해 히스토그램 매칭을 하였다. 본 논문에서 제안된 흔들림 보정 기법은 기존 차량 영상 안정화 기술과 비교하였을 때, 휘도 및 컬러 레벨의 비교를 통해 노이즈가 가장 적고 영상의 자연스러움이 더 뛰어난 복원 결과를 얻을 수 있었다. 또한, 흔들림 보정 기법은 메모리를 사용하지 않고 실시간으로 처리를 통해 다른 방법과 비교하여 효율성을 입증하였다.

• 전자공학회논문지S
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• 제36S권1호
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• pp.104-114
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• 1999

본 논문에서능 2차원 칼라 동영상으로부터 3차원 개인 얼굴 모델을 자동 생성하는 효율적인 방법을 다루었다. 복잡한 배경이 포함된 영상에서 얼굴 영역을 안정적으로 추출하기 위하여 피부 색상 분포에 근거한 색상 움직임 추출 방법을 이용하였다. 검출된 얼굴 영역 내에서 색상 정보과 경계선 정보를 활용하여, MPEG-4의 SNHC(Synthetic-Natural Hybrid Coding) 에서 제안하고 있는 개개인의 얼굴 특성을 표현하는 31개의 얼굴 특징점 파라메타(Facial Description Rarameter: FDP)를 자동 추출하였다. 추출된 2차원 얼굴 특징점을 1038개의 삼각형 메쉬로 이루어진 3차원 일반 얼굴 모델(Generic model)에 적용시켜 변형함으로써 개개인의 얼굴에 해당하는 모델을 자동 생성하였다. 제안하는 알고리듬은 컬러 동영상에서 배경의 복잡성, 얼굴 크기 등에 상관없이 정면상에 가까운 경우 안정적인 특징점을 추출하였으며, 펜티엄 PC에서 약 2초 이내에 개개인의 얼굴 모습에 유사한 얼굴 모델을 생성할 수 있었다.

• Current Optics and Photonics
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• 제3권3호
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• pp.256-262
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• 2019

Extensive tumor resection accompanied by radiotherapy and chemotherapy is the standard of care for malignant gliomas. However, there is a significant obstacle to the complete resection of the tumor due to the difficulty of distinguishing tumor and normal brain tissue with a conventional surgical microscope. Recently, multiple studies have shown the possibility of fluorescence-guided surgery in malignant gliomas. The most used fluorescence dyes for brain tumor surgery are 5-aminolevulinic acid (5-ALA) and indocyanine green (ICG). In this paper, a new fluorescence guided operation system, which can detect both 5-ALA and ICG fluorescent images simultaneously, is presented. This operation system consists of light emitting diodes (LEDs) which emits 410 nm and 740 nm wavelengths. We have performed experiments on rats in order to verify the operation of the newly developed operation system. Oral administration and imaging were performed to observe the fluorescence of 5-ALA and ICG fluorescence in rats. When LEDs at wavelengths of 410 nm and 740 nm were irradiated on rats, 628 nm wavelength with a violet fluorescence color and 825 nm wavelength with a red fluorescence color were expressed in 5-ALA and ICG fluorescent material, respectively, thus we were able to distinguish the tumor tissues easily. Previously, due to the poor resolution of the conventional surgical microscope and the fact that the color of the vein is similar to that of the tumor, the tumor resection margin was not easy to observe, thus increasing the likelihood for cancer recurrence. However, when the tumor is observed through the fluorescence guided operation system, it is possible to easily distinguish the color with the naked eye and it can be completely removed. Therefore, it is expected that surgical removal of cancerous tumors will be possible and surgical applications and surgical microscopes for cancer tumor removal surgery will be promising in the future.