• Title/Summary/Keyword: boundary pixel

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A Generalized Image Interpolation-based Reversible Data Hiding Scheme with High Embedding Capacity and Image Quality

  • Tsai, Yuan-Yu;Chen, Jian-Ting;Kuo, Yin-Chi;Chan, Chi-Shiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.9
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    • pp.3286-3301
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    • 2014
  • Jung and Yoo proposed the first image interpolation-based reversible data hiding algorithm. Although their algorithm achieved superior interpolation results, the embedding capacity was insufficient. Lee and Huang proposed an improved algorithm to enhance the embedding capacity and the interpolation results. However, these algorithms present limitations to magnify the original image to any resolution and pixels in the boundary region of the magnified image are poorly manipulated. Furthermore, the capacity and the image quality can be improved further. This study modifies the pixel mapping scheme and adopts a bilinear interpolation to solve boundary artifacts. The modified reference pixel determination and an optimal pixel adjustment process can effectively enhance the embedding capacity and the image quality. The experimental results show our proposed algorithm achieves a higher embedding capacity under acceptable visual distortions, and can be applied to a magnified image at any resolution. Our proposed technique is feasible in reversible data hiding.

Motion Detection using Adaptive Background Image and A Net Model Pixel Space of Boundary Detection (적응적 배경영상과 그물형 픽셀 간격의 윤곽점 검출을 이용한 객체의 움직임 검출)

  • Lee Chang soo;Jun Moon seog
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.3C
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    • pp.92-101
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    • 2005
  • It is difficult to detect the accurate detection which leads the camera it moves follows in change of the noise or illumination and Also, it could be recognized with backgound if the object doesn't move during hours. In this paper, the proposed method is updating changed background image as much as N*M pixel mask as time goes on after get a difference between imput image and first background image. And checking image pixel can efficiently detect moving by computing fixed distance pixel instead of operate all pixel. Also, set up minimum area of object to use boundary point of object abstracted through checking image pixel and motion detect of object. Therefore motion detection is available as is fast and correct without doing checking image pixel every Dame. From experiment, the designed and implemented system showed high precision ratio in performance assessment more than 90 percents.

Enhanced Graph-Based Method in Spectral Partitioning Segmentation using Homogenous Optimum Cut Algorithm with Boundary Segmentation

  • S. Syed Ibrahim;G. Ravi
    • International Journal of Computer Science & Network Security
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    • v.23 no.7
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    • pp.61-70
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    • 2023
  • Image segmentation is a very crucial step in effective digital image processing. In the past decade, several research contributions were given related to this field. However, a general segmentation algorithm suitable for various applications is still challenging. Among several image segmentation approaches, graph-based approach has gained popularity due to its basic ability which reflects global image properties. This paper proposes a methodology to partition the image with its pixel, region and texture along with its intensity. To make segmentation faster in large images, it is processed in parallel among several CPUs. A way to achieve this is to split images into tiles that are independently processed. However, regions overlapping the tile border are split or lost when the minimum size requirements of the segmentation algorithm are not met. Here the contributions are made to segment the image on the basis of its pixel using min-cut/max-flow algorithm along with edge-based segmentation of the image. To segment on the basis of the region using a homogenous optimum cut algorithm with boundary segmentation. On the basis of texture, the object type using spectral partitioning technique is identified which also minimizes the graph cut value.

Despeckling and Classification of High Resolution SAR Imagery (고해상도 SAR 영상 Speckle 제거 및 분류)

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.25 no.5
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    • pp.455-464
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    • 2009
  • Lee(2009) proposed the boundary-adaptive despeckling method using a Bayesian model which is based on the lognormal distribution for image intensity and a Markov random field(MRF) for image texture. This method employs the Point-Jacobian iteration to obtain a maximum a posteriori(MAP) estimate of despeckled imagery. The boundary-adaptive algorithm is designed to use less information from more distant neighbors as the pixel is closer to boundary. It can reduce the possibility to involve the pixel values of adjacent region with different characteristics. The boundary-adaptive scheme was comprehensively evaluated using simulation data and the effectiveness of boundary adaption was proved in Lee(2009). This study, as an extension of Lee(2009), has suggested a modified iteration algorithm of MAP estimation to enhance computational efficiency and to combine classification. The experiment of simulation data shows that the boundary-adaption results in yielding clear boundary as well as reducing error in classification. The boundary-adaptive scheme has also been applied to high resolution Terra-SAR data acquired from the west coast of Youngjong-do, and the results imply that it can improve analytical accuracy in SAR application.

Moving Object Segmentation using Space-oriented Object Boundary Linking and Background Registration (공간기반 객체 외곽선 연결과 배경 저장을 사용한 움직이는 객체 분할)

  • Lee Ho Suk
    • Journal of KIISE:Software and Applications
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    • v.32 no.2
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    • pp.128-139
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    • 2005
  • Moving object boundary is very important for moving object segmentation. But the moving object boundary shows broken boundary We invent a novel space-oriented boundary linking algorithm to link the broken boundary The boundary linking algorithm forms a quadrant around the terminating pixel in the broken boundary and searches forward other terminating pixel to link within a radius. The boundary linking algorithm guarantees shortest distance linking. We also register the background from image sequence. We construct two object masks, one from the result of boundary linking and the other from the registered background, and use these two complementary object masks together for moving object segmentation. We also suppress the moving cast shadow using Roberts gradient operator. The major advantages of the proposed algorithms are more accurate moving object segmentation and the segmentation of the object which has holes in its region using these two object masks. We experiment the algorithms using the standard MPEG-4 test sequences and real video sequence. The proposed algorithms are very efficient and can process QCIF image more than 48 fps and CIF image more than 19 fps using a 2.0GHz Pentium-4 computer.

Parallel Thinniing Algorithm using Weighted-Value (가중치를 이용한 병렬 세선화 알고리즘)

  • Han, Nak-Hee;Rhee, Phil-Kyu
    • Korean Journal of Cognitive Science
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    • v.7 no.1
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    • pp.5-35
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    • 1996
  • This paper addresses an one-pass parallel thinning algorithm which shows effectiveness in both accuracy and speed. The proposed method is based on parallel iterative boundary removal.Image connectivity are preseved and the algorithms performance is compared to other algorithms especially to parallel thinning algorithm which is the best parallel algorithm have been proposed.Evaluation result shows that the proposed algorithm compare favorably to others.The result shows exact thinning free from one pixel boundary noise and free from distortion of shape.

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Boundary-adaptive Despeckling : Simulation Study

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.25 no.3
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    • pp.295-309
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    • 2009
  • In this study, an iterative maximum a posteriori (MAP) approach using a Bayesian model of Markovrandom field (MRF) was proposed for despeckling images that contains speckle. Image process is assumed to combine the random fields associated with the observed intensity process and the image texture process respectively. The objective measure for determining the optimal restoration of this "double compound stochastic" image process is based on Bayes' theorem, and the MAP estimation employs the Point-Jacobian iteration to obtain the optimal solution. In the proposed algorithm, MRF is used to quantify the spatial interaction probabilistically, that is, to provide a type of prior information on the image texture and the neighbor window of any size is defined for contextual information on a local region. However, the window of a certain size would result in using wrong information for the estimation from adjacent regions with different characteristics at the pixels close to or on boundary. To overcome this problem, the new method is designed to use less information from more distant neighbors as the pixel is closer to boundary. It can reduce the possibility to involve the pixel values of adjacent region with different characteristics. The proximity to boundary is estimated using a non-uniformity measurement based on standard deviation of local region. The new scheme has been extensively evaluated using simulation data, and the experimental results show a considerable improvement in despeckling the images that contain speckle.

Automatic Object Segmentation and Background Composition for Interactive Video Communications over Mobile Phones

  • Kim, Daehee;Oh, Jahwan;Jeon, Jieun;Lee, Junghyun
    • IEIE Transactions on Smart Processing and Computing
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    • v.1 no.3
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    • pp.125-132
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    • 2012
  • This paper proposes an automatic object segmentation and background composition method for video communication over consumer mobile phones. The object regions were extracted based on the motion and color variance of the first two frames. To combine the motion and variance information, the Euclidean distance between the motion boundary pixel and the neighboring color variance edge pixels was calculated, and the nearest edge pixel was labeled to the object boundary. The labeling results were refined using the morphology for a more accurate and natural-looking boundary. The grow-cut segmentation algorithm begins in the expanded label map, where the inner and outer boundary belongs to the foreground and background, respectively. The segmented object region and a new background image stored a priori in the mobile phone was then composed. In the background composition process, the background motion was measured using the optical-flow, and the final result was synthesized by accurately locating the object region according to the motion information. This study can be considered an extended, improved version of the existing background composition algorithm by considering motion information in a video. The proposed segmentation algorithm reduces the computational complexity significantly by choosing the minimum resolution at each segmentation step. The experimental results showed that the proposed algorithm can generate a fast, accurate and natural-looking background composition.

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An Efficient Edge Detection Technique for Separating Regions in an Image (영상내에서 영역 구분을 위한 효율적인 경계검출 기법)

  • Shin, Kwang-seong;Shin, Seong-yoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.05a
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    • pp.359-360
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    • 2021
  • The pixel-based processing of an image refers to a process of converting a value of one pixel only depending on the value of the current pixel, regardless of the value of another pixel. Pixel-based processing is used as the most basic operation in many fields such as image conversion, image enhancement, and image synthesis. There are processing methods such as arithmetic operation, histogram smoothing, and contrast stretching. In this paper, in order to clearly distinguish the tidal flat region from the tidal flat image of the west coast taken with a drone, we seek a method to find an efficient outline using pixel-based processing in the boundary detection part of the pre-processing process.

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Pixel-Isolation Walls of Liquid Crystal Display Formed by Anisotropic Photoreaction of the Prepolymers Containing Cinnamate Moiety

  • Jung, Eun-Ae;Sung, Shi-Joon;Cho, Kuk-Young;Kim, Dae-Hwan;Son, Dae-Ho;Kang, Jin-Kyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.879-882
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    • 2009
  • A pixel isolation wall of liquid crystal display is fabricated by the anisotropic photoreaction of a cinnamate based prepolymer. The various oligomers containing a cinnamate moiety were synthesized and used for the formation of the pixel isolation wall. The anisotropic photoreaction of cinnamate moiety was closely related with the liquid crystal orientation at the polymer wall boundary.

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