• Title/Summary/Keyword: image-photo

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A Study on the Measurement of the Personal Exposure Dose by Film Badge Dosimeter (필름배지선량계에 의한 개인피폭선량 측정에 관한 연구)

  • Chung, Woon-Kwan
    • Journal of Radiation Protection and Research
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    • v.19 no.1
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    • pp.37-50
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    • 1994
  • The experimental evaluation of exposure conversion formula using the relationship between optical photo-density, exposure dose and the quality of radiation characteristics of radiation energy to X-ray and ${\gamma}-rays$. The film badge dosimeter is analysed by exposure conversion formula which evaluate image fading characteristics for development time and directional characteristics for incident beam angle. In conclusion, exposure conversion formula evaluated of this study is satisfied with quality decision criterion of the film badge dosimeter.

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A Study on the effect of JPEG recompression with the color image quality (JPEG 재 압축이 컬러 이미지 품질에 미치는 영향에 관한 연구)

  • 이성형;구철회
    • Proceedings of the Korean Printing Society Conference
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    • 2000.04a
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    • pp.17-24
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    • 2000
  • The Joint Photographic Experts Group (JPEG) is a standara still-image compression technique, established by the International 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 nto the same as values before compression. Image of JPEG compression is often made to JPEG recompression at saving to apply JPEG compression of color image. In general, JPEG is a lossy compression and compression image is predicted to be varied image quality according to recompressed Q-factor. Various distortions of JPEG compression and JPEG recompression has been reported in previous paper. In this paper, we compress four difference color samples (photo image, gradient image, vector drawing image, text image) according to various Q-factor, and then compressed images are recompressed according to various Q-factor once again. As the results, we inspect variation of quality and file size of recompressed color image, and ensure the optimum recompression factor.

A study on the effect of JPEG recompression with the color image quality (JPEG 재압축이 컬러 이미지 품질에 미치는 영향에 관한 연구)

  • 이성형;조가람;구철희
    • Journal of the Korean Graphic Arts Communication Society
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    • v.18 no.2
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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.

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Image Retrieval Using the Fusion of Spatial Histogram and Wavelet Moments (공간 히스토그램과 웨이브릿 모멘트의 융합에 의한 영상검색)

  • 서상용;손재곤;김남철
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.11-14
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    • 2000
  • We present an image retrieval method that improves retrieval rate by using the fusion of histogram and wavelet moment features. The key idea is that images similar to a query image are selected in DB by using the wavelet moment features. Then the result images are retrieved from the selected images by using histogram method. In order to evaluate the performance of the proposed method, we use Brodatz texture database, MPEG-7 T1 database and Corel Draw photo. Experimental result shows that the proposed method is better than each of histogram method and wavelet moment method.

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Fast Detection of Forgery Image using Discrete Cosine Transform Four Step Search Algorithm

  • Shin, Yong-Dal;Cho, Yong-Suk
    • Journal of Korea Multimedia Society
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    • v.22 no.5
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    • pp.527-534
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    • 2019
  • Recently, Photo editing softwares such as digital cameras, Paintshop Pro, and Photoshop digital can create counterfeit images easily. Various techniques for detection of tamper images or forgery images have been proposed in the literature. A form of digital forgery is copy-move image forgery. Copy-move is one of the forgeries and is used wherever you need to cover a part of the image to add or remove information. Copy-move image forgery refers to copying a specific area of an image itself and pasting it into another area of the same image. The purpose of copy-move image forgery detection is to detect the same or very similar region image within the original image. In this paper, we proposed fast detection of forgery image using four step search based on discrete cosine transform and a four step search algorithm using discrete cosine transform (FSSDCT). The computational complexity of our algorithm reduced 34.23 % than conventional DCT three step search algorithm (DCTTSS).

3D Analysis of Scene and Light Environment Reconstruction for Image Synthesis (영상합성을 위한 3D 공간 해석 및 조명환경의 재구성)

  • Hwang, Yong-Ho;Hong, Hyun-Ki
    • Journal of Korea Game Society
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    • v.6 no.2
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    • pp.45-50
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    • 2006
  • In order to generate a photo-realistic synthesized image, we should reconstruct light environment by 3D analysis of scene. This paper presents a novel method for identifying the positions and characteristics of the lights-the global and local lights-in the real image, which are used to illuminate the synthetic objects. First, we generate High Dynamic Range(HDR) radiance map from omni-directional images taken by a digital camera with a fisheye lens. Then, the positions of the camera and light sources in the scene are identified automatically from the correspondences between images without a priori camera calibration. Types of the light sources are classified according to whether they illuminate the whole scene, and then we reconstruct 3D illumination environment. Experimental results showed that the proposed method with distributed ray tracing makes it possible to achieve photo-realistic image synthesis. It is expected that animators and lighting experts for the film and animation industry would benefit highly from it.

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A study on improvement of convergent measurement performance of color display tube using photo sensors (포토 센서를 이용한 브라운관의 컨버젼스 측정 성능 향상에 관한 연구)

  • ;;Zeungnam Bien
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.3
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    • pp.93-101
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    • 1998
  • In Integrated Tube Components(ITC) process in themanufacturing of color display tube, we describe the necessity of the convergence measurement method using photo sensors. Compared with methods using 1D or 2D cameras, its characteristics is to use of moving image patterns and fixed sensors. This measurement method is formulated as the measurement problem of the phase difference in phase changing periodic signals. The convergence measurement system using photo sensors, for the good performance, must have a small standard deviation for the repetitive measurement in the same condition and a fast measurement time for thecovergence change. By above two conditions, we proposed the real time measurement algorithm of the pahse difference using fundametal and harmonic in phase changing periodic signals. And, the proposed algorithm is applied to the convergence measurement system.

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Distinction of Real Face and Photo using Stereo Vision (스테레오비전을 이용한 실물 얼굴과 사진의 구분)

  • Shin, Jin-Seob;Kim, Hyun-Jung;Won, Il-Yong
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.7
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    • pp.17-25
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    • 2014
  • In the devices that leave video records, it is an important issue to distinguish whether the input image is a real object or a photo when securing an identifying image. Using a single image and sensor, which is a simple way to distinguish the target from distance measurement has many weaknesses. Thus, this paper proposes a way to distinguish a simple photo and a real object by using stereo images. It is not only measures the distance to the target, but also checks a three-dimensional effect by making the depth map of the face area. They take pictures of the photos and the real faces, and the measured value of the depth map is applied to the learning algorithm. Exactly through iterative learning to distinguish between the real faces and the photos looked for patterns. The usefulness of the proposed algorithm was verified experimentally.

A study on quality transformation of Digital printing photograph according to Comporession Method (압축방식에 따른 디지털 인쇄사진의 품질 변화에 관한 연구)

  • Cho, Ga-Ram;Koo, Chul-Whoi
    • Journal of the Korean Graphic Arts Communication Society
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    • v.21 no.1
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    • pp.35-44
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    • 2003
  • Because of computer developing, the digital image making the use of many a field of application with - web-above, electronic publishing. printing, dynamic image management and photo CD production etc., however many problems of save and management. The management image use of compression moth which don't have a affect on image, reduce file size. A study used sequential DCT0based mode and progressive DCT-based mode of JPEG(Joing Photographic Experts Group) compression method and Wavelet compression method. Therefore, the analog image and digital image was changed and applied by several stages according to compression rate. It made inquiries of the optimum compression rate that be compared quality transformation between original image and compressed image. As compression image was printing simply, the quality was studied by subjective valuation method, that was studied propriety and usefulness.

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Simpson Style Caricature based on MLS

  • Lee, Jiye;Byun, Hae Won
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.6
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    • pp.1449-1462
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    • 2013
  • We present a novel approach to producing facial caricature with Simpson cartoon style based on Moving Least Squares (MLS). We take advantage of employing the caricature stylization rule of caricature artist, Justin. Our method allows Simpson-style cartoon character similar to user's features by using Justin's technique, which is a set of caricature stylization rules. Our method transforms input photo image into Simpson style caricature by using MLS approximation. The unique characteristics of user in the photo can be detected by comparing to the mean face feature and the input face feature extracted by AAM(Active Appearance Model). To exaggerate the detected unique characteristics, we set up the exaggeration rules using Justin's technique. In addition, during the cartooning process, user's hairs and accessories are used to the deformed image to make a close resemblance. Our method preserves the reliable and stylized caricature through the exaggeration rules of the actual caricature artist's techniques. From this study, we can easily create a Simpson-style cartoon caricature to resemble user's features by combining a caricature with existing cartoon researches.