• Title/Summary/Keyword: Image Edge

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A Study on the Lossless Image Compression using Context based Predictive Technique of Error Feedback (에러 피드백의 컨텍스트 기반 예측기법을 이용한 무손실 영상 압축에 관한 연구)

  • Chu, Hyung-Suk;Park, Byung-Su;An, Chong-Koo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.12
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    • pp.2251-2256
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    • 2007
  • In this paper, the wavelet transform based lossless image compression algorithm is proposed. The proposed algorithm transforms the input image using 9/7 ICFB and S+P filter, and eliminates the spacious correlation of the subband coefficients, applying the context modeling predictive technique based on the multi-resolution structure and the feedback of the prediction error. The prediction context exploits the subordination and direction property of the different level subband in the vertical, horizontal, and diagonal subband coefficients. The simulation result of the high frequency images such as PEPPERS, BOAT, and AIRPLANE shows that the proposed algorithm efficiently predicts the edge area of each multi-resolution subband.

CONVERTING BITMAP IMAGES INTO SCALABLE VECTOR GRAPHICS

  • Zhou, Hailing;Zheng, Jianmin;Seah, Hock Soon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.435-440
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    • 2009
  • The scalable vector graphics (SVG) standard has allowed the complex bitmap images to be represented by vector based graphics and provided some advantages over the raster based graphics in applications, for example, where scalability is required. This paper presents an algorithmto convert bitmap images into SVG format. The algorithm is an integration of pixel-level triangulation, data dependent triangulation, a new image mesh simplification algorithm, and a polygonization process. Both triangulation techniques enable the image quality (especially the edge features) to be preserved well in the reconstructed image and the simplification and polygonization procedures reduce the size of the SVG file. Experiments confirm the effectiveness of the proposed algorithm.

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A Novel DWT-SVD Canny-Based Watermarking Using a Modified Torus Technique

  • Lalani, Salima;Doye, D.D.
    • Journal of Information Processing Systems
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    • v.12 no.4
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    • pp.681-687
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    • 2016
  • Today's modern world requires a digital watermarking technique that takes the redundancy of an image into consideration for embedding a watermark. The novel algorithm used in this paper takes into consideration the redundancies of spatial domain and wavelet domain for embedding a watermark. Also, the cryptography-based secret key makes the algorithm difficult to hack and help protect ownership. Watermarking is blind, as it does not require the original image. Few coefficient matrices and secret keys are essential to retrieve the original watermark, which makes it redundant to various intentional attacks. The proposed technique resolves the challenge of optimizing transparency and robustness using a Canny-based edge detector technique. Improvements in the transparency of the cover image can be seen in the computed PSNR value, which is 44.20 dB.

Medical Image Retrieval Using Feature Extraction Based on Wavelet Transform (웨이블렛 변환 기반의 특징 검출을 이용한 의료영상 검색)

  • Lee, H.S.;Ma, K.Y.;Ahn, Y.B.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.321-322
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    • 1998
  • In this paper, a medical images retrieval method using feature extraction based on wavelet transform is proposed. We used energy of coefficients which is represented by wavelet transform. The proposed retrieval algorithm is comprised of the two retrieval. At first, we make a energy map for wavelet coefficient of a query image and then compare is to one of db image. And then we use an edge information of the query image to retrieve the images selected at the first retrieval once more. Consequently some retrieved images are displayed on screen.

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SAR Despeckling with Boundary Correction

  • Lee, Sang-Hoon
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.270-273
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    • 2007
  • In this paper, a SAR-despeck1ing approach of adaptive iteration based a Bayesian model using the lognormal distribution for image intensity and a Gibbs random field (GRF) for image texture is proposed for noise removal of the images that are corrupted by multiplicative speckle noise. When the image intensity is logarithmically transformed, the speckle noise is approximately Gaussian additive noise, and it tends to a normal probability much faster than the intensity distribution. The MRF is incorporated into digital image analysis by viewing pixel types as states of molecules in a lattice-like physical system. The iterative approach based on MRF is very effective for the inner areas of regions in the observed scene, but may result in yielding false reconstruction around the boundaries due to using wrong information of adjacent regions with different characteristics. The proposed method suggests an adaptive approach using variable parameters depending on the location of reconstructed area, that is, how near to the boundary. The proximity of boundary is estimated by the statistics based on edge value, standard deviation, entropy, and the 4th moment of intensity distribution.

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Building Recognition using Image Segmentation and Color Features (영역분할과 컬러 특징을 이용한 건물 인식기법)

  • Heo, Jung-Hun;Lee, Min-Cheol
    • The Journal of Korea Robotics Society
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    • v.8 no.2
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    • pp.82-91
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    • 2013
  • This paper proposes a building recognition algorithm using watershed image segmentation algorithm and integrated region matching (IRM). To recognize a building, a preprocessing algorithm which is using Gaussian filter to remove noise and using canny edge extraction algorithm to extract edges is applied to input building image. First, images are segmented by watershed algorithm. Next, a region adjacency graph (RAG) based on the information of segmented regions is created. And then similar and small regions are merged. Second, a color distribution feature of each region is extracted. Finally, similar building images are obtained and ranked. The building recognition algorithm was evaluated by experiment. It is verified that the result from the proposed method is superior to color histogram matching based results.

Stereo Image Processing Algorithm to Preceding Vehicle Detection Based on DLI (차선변이 함수 기반의 선행차량 인식 알고리즘)

  • 황희정;백광렬;이운근
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.7
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    • pp.509-516
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    • 2004
  • This paper proposes an image processing algorithm for detecting obstacles on road using DLI(disparity of lane-related information) that is generated by stereo images acquired from dual cameras mounted on a moving vehicle. The DLI is a disparity that is acquired using a single lane information from road lane detection. For the purpose to reduce processing time, we use small block of edge-histogram based blocking logic. This algorithm detects moving objects such as preceding vehicles and obstacles. The proposed algorithm has been implemented in a personal computer with the road image data of a typical highway. We successfully performed experiments under a wide variety of road conditions without changing parameter values or adding human intervention. Experimental results also showed that the proposed DLI is quite successful.

Performance Analysis of Deep Learning-based Image Super Resolution Methods (딥 러닝 기반의 초해상도 이미지 복원 기법 성능 분석)

  • Lee, Hyunjae;Shin, Hyunkwang;Choi, Gyu Sang;Jin, Seong-Il
    • IEMEK Journal of Embedded Systems and Applications
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    • v.15 no.2
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    • pp.61-70
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    • 2020
  • Convolutional Neural Networks (CNN) have been used extensively in recent times to solve image classification and segmentation problems. However, the use of CNNs in image super-resolution problems remains largely unexploited. Filter interpolation and prediction model methods are the most commonly used algorithms in super-resolution algorithm implementations. The major limitation in the above named methods is that images become totally blurred and a lot of the edge information are lost. In this paper, we analyze super resolution based on CNN and the wavelet transform super resolution method. We compare and analyze the performance according to the number of layers and the training data of the CNN.

Development of Real-Time Image Processing System Using GPU (GPU를 이용한 실시간 이미지 프로세싱 시스템)

  • Oh Jae-Hong;Kang Hoon;Lee Ja-Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.5
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    • pp.393-397
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    • 2005
  • When a real-time image processing application is implemented with a general-purpose computer, CPU (Central Processing Unit) is usually heavily loaded and in many cases that CPU alone cannot meet the real-time requirement at all. Most modern computers are equipped with powerful Graphics Processing Units (GPUs) to accelerate graphics operations. There is a trend that the power of GPU outgrows that of CPU. If we take advantage of the powerful GPU for more general operations other than pure graphics operations, the processing time can be reduced. In this study, we will present techniques that apply GPU to general operations such as image processing procedures. Our experiment results show that significant speed-up can be achieved by using GPU.

Consideration of Image Quality of Dithered Picture by Constrained Average Method Using Various Probability Distribution Models

  • Sato, Mitsuhiro;Hasegawa, Madoka;Kato, Shigeo
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1495-1498
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    • 2002
  • The constrained average method is one of dither methods which combines edge emphasis and grayscale rendition to provide legibility of textual region and proper quality of continuous tone region. How-ever, image quality of continuous tone region is insufficient compared to other dither methods, such as ordered dither methods or the error diffusion method. The constrained average method uses a uniform distribution function to decide number of lit pixels related to the average intensity in a picture area. However, actual distribution of continuous tone region is closer to the Laplacian distribution or triangle distribution. In this paper, we introduce various probability distributions and the actual luminance distribution to decide the threshold value of the constrained average method in order to improve image quality of dithered image.

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