• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.1
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• pp.17-25
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• 1996

The development of still video CCD cameras has simplified dramatically the digital imaging process. Still video cameras have flexibility that allows digital image acquisition and on-board image storage without being connected to a computer. The objective of this paper is to evaluate the performance of digital close-range photogrammetric system using the still video camera for dimensional inspection and structural monitoring being required in various industries. Some sub-pixel measurement techniques, which is indispensable for digital image measurement, were suggested. The author carried out the self-calibration of a high resolution DCS420 still video camera and then test application of a structure. The self-calibrating bundle adjustments resulted in object space accuracies which exceed 1 :46,000. It is ascertained that this digital close-range photogrammetric system has high accuracy potential and task effectiveness for industrial applications.

• Journal of Korea Multimedia Society
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• v.19 no.6
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• pp.990-1002
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• 2016

In this paper, we propose a new compression method for the edge image by analyzing the characteristics and the distribution of pixel values of the edge image. The pixel values of the edge image have the Gaussian distribution around '0', and most of the pixel values are `0`. By these analyses we suggest the Zero-Based codec that expresses all values in a CU by a single bit flag. Also, in order to reduce the computational complexity of the proposed codec, the block partition and the intra-prediction techniques are proposed by using edge information like the number of each edge direction, the distribution and the amplitude of a major edge direction in the CU. Experimental results show that the proposed codec leads to a slighter distortion in Y domain than that of HEVC, but has far faster processing speed up to 53 times while it maintains the similar image quality compared to HEVC.

• Journal of Korea Multimedia Society
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• v.7 no.12
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• pp.1692-1699
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• 2004

Many researchers have developed various techniques for detection of human faces in ordinary still images. Face detection is the first imperative step of human face recognition systems. The two main problems of human face detection are how to cutoff the running time and how to reduce the number of false positives. In this paper, we present frontal and near-frontal face detection algorithm in still gray images using a thick edge image and neural network. We have devised a new filter that gets the thick edge image. Our overall scheme for face detection consists of two main phases. In the first phase we describe how to create the thick edge image using the filter and search for face candidates using a whole face detector. It is very helpful in removing plenty of windows with non-faces. The second phase verifies for detecting human faces using component-based eye detectors and the whole face detector. The experimental results show that our algorithm can reduce the running time and the number of false positives.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.301-302
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• 2006

Load effect which occurs due to the electrode structure for PDP(plasma display panel) can seriously reduce the image quality of PDP. In this paper, we propose the method of reducing load effect in presentation images, which have the possibility of load effect, by using LUT(look-up table). The proposed method enhances the image quality of PDP by correcting load effect region of the still image.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1995.06a
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• pp.91-96
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• 1995

In this paper we propose algorithms for high resolution image sequence interpolation. Image sequences, in general, are assumed to have greater amount of information than a still image. By this reason, image sequences can be used to improve the resolution of interpolated image sequences. Therefore the proposed algorithms can be the theoretical basis for interpolating dynamic image sequences. In order to demonstrate the validity of the proposed algorithms, experimental results using both synthetic and real test images are presented.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.2
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• pp.25-32
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• 2004

Purpose : The simulator is used to determine patient field and ensure the treatment field, which encompasses the required anatomy during patient normal movement such as during breathing. The latest simulator provide real time display of still, flouroscopic and digitalized image, but conventional simulator is not yet. The purpose of this study is to introduce digital image capture system(DICS) using conventional simulator and clinical case using digital captured still and flouroscopic image. Methods and materials : We connect the video signal cable to the video terminal in the back up of simulator monitor, and connect the video jack to the A/D converter. After connection between the converter jack and computer, We can acquire still image and record flouroscopic image with operating image capture program. The data created with this system can be used in patient treatment, and modified for verification by using image processing software. (j.e. photoshop, paintshop) Result : DICS was able to establish easy and economical procedure. DCIS image was helpful for simulation. DICS imaging was powerful tool in the evaluation of the department specific patient positioning. Conclusion : Because the commercialized simulator based of digital capture is very expensive, it is not easily to establish DICS simulator in the most hospital. DICS using conventional simulator enable to utilize the practical use of image equal to high cost digitalized simulator and to research many clinical cases in case of using other software program.

• ETRI Journal
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• v.9 no.3
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• pp.115-126
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• 1987

자연화(Natural Image)는 CCITT SG Vlll에서 통용되는 기술용어로서 정지된 컬러 영상(Still Full Color Image)을 의미한다. 자연화는 많은 정보를 내포하고 높은 신뢰도를 갖기때문에 자연화 통신기술의 중요성이 날로 증대되고 있다. 본고에서는 자연화 통신에 필요한 영상정보 압축기술의 현황을 분석하고 또한 국제표준화 기술동향을 설명하였다.

• Journal of Broadcast Engineering
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• v.2 no.2
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• pp.104-113
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• 1997

In this paper, we investigate on the techniques for still image compression based on the wavelet transform, which will be adopted as a part of the MPEG-4 compression standards. Also we propose an effective still image compression technique, which is simpler than the MPEG-4 compression method and is improved by using a visually weighted quantizer based to HVS(Human Visual System), Simulations are carried out and compared with the algorithm proposed in MPEG-4. The simulation results show that the proposed method in this paper gives much better image quality than that of the method in MPEG-4. Also, except the case where the compression ratio is high, it shows that the proposed method has lower in complexity and provides a better subjective and objective image quality than EZW in most cases. Since wavelet transform well reflects HVS, the compressed image rarely causes blocking artifact compared with JPEG, and in most cases, it shows considerable quality improvement over JPEG.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.491-494
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• 1999

Introduction of digital communication network such as Integrated Services Digital Networks(ISDN) and digital storage media have rapidly developed. Due to a large amount of image data, compression is the key techniques in still image and video using digital signal processing for transmitting and storing. Digital image compression provides solutions for various image applications that represent digital image requiring a large amount of data. In this paper, the proposed DWT(Discrete Wavelet Transform) filter bank is consisted of simple architecture, but it is efficiently designed that a user obtain a wanted compression rate as only input parameter. If it is implemented by FPGA chip, the designed encoder operates in 12MHz.

• Journal of Internet Computing and Services
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• v.6 no.5
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• pp.133-141
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• 2005

In this paper, we designed about OFDM/QPSK image transmission system simulator embedded watermark in wireless channel environment. Channel environment used OFDM/QPSK still image transmission system considering AWGN, Multi-path fading. And, we analyzed effect of still image and watermark information in considered channel environment. Watermark information is coded by DM-SS (Direct Matric/Spread Spectrum) image watermarking scheme, Also, we used interleaving scheme for mitigating the degradation in watermarking data under wireless channel. As a results, we could know that PSNR of watermark image improved of about 1dB by 54.2371dB then apply interleaving in same multi-path fading environment.