• Title/Summary/Keyword: Video Distortion

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An Effective Detection of Print Image Forgeries Based on Modeling of Color Matrix : An Application to QR Code (컬러 매트릭스 모델링에 의한 영상 인쇄물 위변조 검출 기법 : QR코드에의 적용)

  • Choi, Do-young;Kim, Jin-soo
    • The Journal of the Korea Contents Association
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    • v.18 no.10
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    • pp.431-442
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    • 2018
  • 2-dimensional barcode, QR code has been used for containing various information such as image, video, map, and business cards. Currently, a smartphone is used as a QR code scanner, displaying the code and converting it to a standard URL for a website. However, QR codes are not very common in encrypted application and so have a few applications. This paper proposes a new color-code, which integrates the conventional QR code and color design, and can be effectively used in some product certification system. The proposed method exploits the fact that genuine code is produced by CMYK color model, but the counterfeit is captured by RGB color model and during this process, color information of the code is changed. This paper introduces the color matrix model to measure the distortion between genuine code and counterfeit code. By investigating the statistical characteristics of color matrix, an effective detection of print image forgeries are designed. Various experiments with color codes show that the proposed system can be effectively used in product certification systems.

Development of Adaptive Digital Image Watermarking Techniques (적응형 영상 워터마킹 알고리즘 개발)

  • Min, Jun-Yeong
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.4
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    • pp.1112-1119
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    • 1999
  • Digital watermarking is to embed imperceptible mark into image, video, audio and text data to prevent the illegal copy of multimedia data, arbitrary modification, and also illegal sales of the copes without agreement of copyright ownership. The DCT(discrete Cosine Transforms) transforms of original image is conducted in this research and these DCT coefficients are expanded by Fourier series expansion algorithm. In order to embed the imperceptible and robust watermark, the Fourier coefficients(lower frequency coefficients) can be calculated using sine and cosine function which have a complete orthogonal basis function, and the watermark is embedded into these coefficients, In the experiment, we can show robustness with respect to image distortion such as JPEG compression, bluring and adding uniform noise. The correlation coefficient are in the range from 0.5467 to 0.9507.

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Fast Mode Decision in H.264/AVC Using Adaptive Selection of Reference Frame and Selective Intra Mode (다중 참조 영상의 적응적 선택 및 선택적 인트라 모드를 이용한 H.264/AVC의 고속 모드 결정 방법)

  • Lee Woong-Ho;Lee Jung-Ho;Cho Ik-Hwan;Jeong Dong-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.3C
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    • pp.271-278
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    • 2006
  • Rate-constrained coding is one of the many coding-efficiency oriented tools of H.264/AVC, but mode decision process of RDO(Rate distortion optimization) requires high computational complexity. Many fast mode decision algorithms have been proposed to reduce the computational complexity of mode decision. In this paper, we propose two algorithms for reduction of mode decision in H.264/AVC, which are the fast reference frame selection and selective intra prediction mode decision. Fast reference frame selection is efficient for inter predication and selective intra prediction mode decision can effectively reduce excessive calculation load of intra prediction mode decision. The simulation results showed that the proposed methods could reduce the encoding time of the overall sequences by 44.63% on average without any noticeable degradation of the coding efficiency.

An Efficient Data-reuse Deblocking Filter Algorithm for H.264/AVC (H.264/AVC 비디오 코덱을 위한 효율적인 자료 재사용 디블록킹 필터 알고리즘)

  • Lee, Hyoung-Pyo;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.6
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    • pp.30-35
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    • 2007
  • H.264/AVC provides better quality than other algorithms by using a deblocking filter to remove blocking distortion on block boundary of the decoded picture. However, this filtering process includes lots of memory accesses, which cause delay of overall decoding time. In this paper, we propose a data-reuse algorithm to speed up the process for the deblocking filter. To reuse the data, a new filtering order is suggested. By using this order, we reduce the memory access and accelerate the deblocking filter. The modeling of proposed algorithm is compiled under ARM ADS1.2 and simulated with Armulator. The results of the experiment compared with H.264/AVC standard are achieved on average 58.45% and 57.93% performance improvements at execution cycles and memory access cycles, respectively.

Fast Intra Coding using DCT Coefficients (DCT 계수를 이용한 고속 인트라 코딩)

  • Kim, Ga-Ram;Kim, Nam-Uk;Lee, Yung-Lyul
    • Journal of Broadcast Engineering
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    • v.20 no.6
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    • pp.862-870
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    • 2015
  • The RDO (Rate Distortion Optimization) process of HEVC results in good coding efficiency, but relatively requires much encoding time. In order to reduce the encoding time of RDO process, this paper proposes a method of fast intra prediction mode decision using DCT coefficients distributions and the existence of DCT coefficients. The proposed fast Intra coding sets the number of intra prediction mode candidates to three(3) from the RMD (Rough Mode Decision) process in HM16.0 reference SW and reduces the number of candidates one more time by investigating DCT coefficients distribution. After that, if there exists a quantized DCT block having all zero coefficient values for a specific candidate before the RDO process, the candidate is chosen without the RDO process. The proposed method reduces the encoder complexity on average 46%, while the coding efficiency is 2.1% decreased compared with the HEVC encoder.

A Study on the Application of Computers to the Development of Humor Image Fashion Design (컴퓨터를 활용한 유머 이미지 패션디자인 개발에 관한 연구)

  • 우세희;최현숙
    • Journal of the Korean Society of Costume
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    • v.53 no.5
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    • pp.65-77
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    • 2003
  • Due to the rapid changes occurring in many aspects of contemporary society, the need for a means to actively combat widespread feelings of emptiness and alienation among the public, while satisfying its visual pleasure, is increasing. Thus the need for humorous elements which bring freedom to the human psyche is urgently requested. Of course, the field of fashion cannot be left out in this trend, and humor image design is a good example of this. Humor image in fashion endeavors to release the tension accumulated in the modern world, while trying to find a way to recover the original pureness of mankind. Another aspect currently important is computers. The creation of images in modern visual art relies a lot upon computers. Traditional visual processes such as painting, photography and video are now merged within digital technology. and are now quite symbiotic to each other. With the development of computers came computer art. which uses all applicable functions of a computer to create art. Any artistic action which uses a computer in any stage of its creation can be called computer art. The common factor in humor and computer art in modern fashion can be classified as follows : repetition, deformation and distortion. exaggeration and abridgement. juxtaposition. and Tromp l'oeil. This study has placed its objective on the fusion of humor image fashion and computer art, by manufacturing a work with humor and computers, two important aspects of modern culture. Expanding the field of fashion design while promoting creativity In fashion by finding a verging point between art and science is also necessary. I have designed and made five costumes using the above cited techniques in computer humor images, on a theoretical basis.

An HEVC intra encoder sharing DCT with RDO for a low complex hardware (하드웨어 복잡도를 줄이기 위한 RDO내 DCT 공유구조의 HEVC 화면내 예측부호화기)

  • Lee, Sukho;Jang, Juneyoung;Byun, Kyungjun;Eum, Nakwoong
    • Smart Media Journal
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    • v.3 no.4
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    • pp.16-21
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    • 2014
  • HEVC is the latest joint video coding standard with ITU-T SG16 WP and ISO/IEC JTC1/SC29/WG11. Its coding efficiency is about two times compared to H.264 high profile. Intra prediction has 35 directional modes including dc and planer. However an accurate mode decision on lots of modes with SSE is too costly to implement it with hardware. The key idea of this paper is a DCT shared architecture to reduce the complexity of HEVC intra encoder. It is to use same DCT block to quantize as well as to calculate SSE in RDO. The proposed intra encoder uses two step mode decision to lighten complexity with simplified RDO blocks and shares the transform resources. Its BD-rate increase is negligible at 20% on hardware aspect and the operating clock frequency is 300MHz@60fps on FHD ($1920{\times}1080$) image.

A Study on the Multiresolution Motion Estimation Adequate to Low-Band-Shift Method in Wavelet Domain (웨이블릿 변환 영역에서 저대역 이동법에 적합한 다해상도 움직임 추정에 관한 연구)

  • 조재만;김현민;고형화
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.2C
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    • pp.110-120
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    • 2003
  • In this paper, we propose a Multiresolution Motion Estimation(MRME) adapted to Low-Band-Shift(LBS) method in wavelet domain. To overcome shift-variant property on wavelet coefficients, the LBS was previously proposed. This method which is applied to reference frame in video coding technique, has superior performance in terms of rate-distortion characteristic. However, this method needs more memory and computational complexity. In this paper, The computational complexity of the proposed method(LBS-MRME) is about 15.6% of that of existing method at 3-level wavelet transform. And although it has about 7 times as much as existing method's motion vector since each subband has different motion vector, it decreases motion compensated prediction error by detailed motion estimation, and then has better efficient coding performance. The experimental results with the proposed method showed about 0.3∼11.6% improvement of MAD performance in case of lossless coding, and 0.3∼3.0㏈ improvement of PSNR performance at the same bit rate in case of lossy coding.

Analysis on Characteristics of Representation of Surrealism on Fantasy Online Game's Character (판타지 온라인 게임의 캐릭터에 관한 초현실주의의 표현 특징 분석)

  • Kim, Kyoung-Nam;Lee, Myoun-Jae
    • Journal of Korea Game Society
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    • v.5 no.4
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    • pp.3-12
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    • 2005
  • Many works have been published with using surrealism techniques among the representation characteristics of media space of video and art. It has begun to research on these work. But many of these researches have not cover surrealism techniques in game graphic. So, in this paper, we have analyzed representation characteristics of fantasy online game's character using surrealism techniques in surrealism. In result, there are means to express nonexistent image in real world in surrealism by using such as collage of parts of body, animals, and other object, deformation, and distortion. Also, these methods have been used in game characters of online game based on fantasy. We analyzed on characteristics of fantasy game's character in aesthetic point view. It should be profitable for making creative and favorable game characters and making creative game graphic by increasing the possibility of art techniques usage.

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Fast Inter Block Mode Decision Using Image Complexity in H.264/AVC (H.264/AVC에서 영상 복잡도를 이용한 고속 인터 블록 모드 결정)

  • Kim, Seong-Hee;Oh, Jeong-Su
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.11C
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    • pp.925-931
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    • 2008
  • In video coding standard H.264/AVC, variable block size mode algorithm improves compression efficiency but has need of a large amount of computation for various block modes and mode decision. Meanwhile, decided inter block modes depend on the complexity of a block image, and then the more complex a macroblock is, the smaller its block size is. This paper proposes fast inter block mode decision algorithm. It limits valid block modes to the block modes with a great chance for decision using the image complexity and carries out motion estimation rate-distortion optimization with only the valid block modes. In addition to that, it applies fast motion estimation PDE to the valid block modes with only the $16{\times}16$ block mode. The reference software JM 9.5 was executed to estimate the proposed algorithm's performance. The simulation results showed that the proposed algorithm could save about 24.12% of the averaged motion estimation time while keeping the image quality and the bit rate to be -0.02dB and -0.12% on the average, respectively.