• Title/Summary/Keyword: Markov random field

Search Result 97, Processing Time 0.037 seconds

An Edge-Based Algorithm for Discontinuity Adaptive Image Smoothing (에지기반의 불연속 경계적응 영상 평활화 알고리즘)

  • 강동중;권인소
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.273-273
    • /
    • 2000
  • We present a new scheme to increase the performance of edge-preserving image smoothing from the parameter tuning of a Markov random field (MRF) function. The method is based on automatic control of the image smoothing-strength in MRF model ing in which an introduced parameter function is based on control of enforcing power of a discontinuity-adaptive Markov function and edge magnitude resulted from discontinuities of image intensity. Without any binary decision for the edge magnitude, adaptive control of the enforcing power with the full edge magnitude could improve the performance of discontinuity-preserving image smoothing.

  • PDF

MRF-based Fuzzy Classification Using EM Algorithm

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
    • /
    • v.21 no.5
    • /
    • pp.417-423
    • /
    • 2005
  • A fuzzy approach using an EM algorithm for image classification is presented. In this study, a double compound stochastic image process is assumed to combine a discrete-valued field for region-class processes and a continuous random field for observed intensity processes. The Markov random field is employed to characterize the geophysical connectedness of a digital image structure. The fuzzy classification is an EM iterative approach based on mixture probability distribution. Under the assumption of the double compound process, given an initial class map, this approach iteratively computes the fuzzy membership vectors in the E-step and the estimates of class-related parameters in the M-step. In the experiments with remotely sensed data, the MRF-based method yielded a spatially smooth class-map with more distinctive configuration of the classes than the non-MRF approach.

Natural Scene Text Binarization using Tensor Voting and Markov Random Field (텐서보팅과 마르코프 랜덤 필드를 이용한 자연 영상의 텍스트 이진화)

  • Choi, Hyun Su;Lee, Guee Sang
    • Smart Media Journal
    • /
    • v.4 no.4
    • /
    • pp.18-23
    • /
    • 2015
  • In this paper, we propose a method for detecting the number of clusters. This method can improve the performance of a gaussian mixture model function in conventional markov random field method by using the tensor voting. The key point of the proposed method is that extracts the number of the center through the continuity of saliency map of the input data of the tensor voting token. At first, we separate the foreground and background region candidate in a given natural images. After that, we extract the appropriate cluster number for each separate candidate regions by applying the tensor voting. We can make accurate modeling a gaussian mixture model by using a detected number of cluster. We can return the result of natural binary text image by calculating the unary term and the pairwise term of markov random field. After the experiment, we can confirm that the proposed method returns the optimal cluster number and text binarization results are improved.

Image Dehazing using Transmission Map Based on Hidden Markov Random Field Model (은닉 마코프 랜덤 모델 기반의 전달 맵을 이용한 안개 제거)

  • Lee, Min-Hyuk;Kwon, Oh-Seol
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.1
    • /
    • pp.145-151
    • /
    • 2014
  • This paper proposes an image haze removal algorithm for a single image. The conventional Dark Channel Prior(DCP) algorithm estimates a transmission map using the dark information in an image, and the haze regions are then detected using a matting algorithm. However, since the DCP algorithm uses block-based processing, block artifacts are invariably formed in the transmission map. To solve this problem, the proposed algorithm generates a modified transmission map using a Hidden Markov Random Field(HMRF) and Expectation-Maximization(EM) algorithm. Experimental results confirm that the proposed algorithm is superior to conventional algorithms in image haze removal.

Moving Shadow Detection using Deep Learning and Markov Random Field (딥 러닝과 마르코프 랜덤필드를 이용한 동영상 내 그림자 검출)

  • Lee, Jong Taek;Kang, Hyunwoo;Lim, Kil-Taek
    • Journal of Korea Multimedia Society
    • /
    • v.18 no.12
    • /
    • pp.1432-1438
    • /
    • 2015
  • We present a methodology to detect moving shadows in video sequences, which is considered as a challenging and critical problem in the most visual surveillance systems since 1980s. While most previous moving shadow detection methods used hand-crafted features such as chromaticity, physical properties, geometry, or combination thereof, our method can automatically learn features to classify whether image segments are shadow or foreground by using a deep learning architecture. Furthermore, applying Markov Random Field enables our system to refine our shadow detection results to improve its performance. Our algorithm is applied to five different challenging datasets of moving shadow detection, and its performance is comparable to that of state-of-the-art approaches.

Moving object segmentation using Markov Random Field (마코프 랜덤 필드를 이용한 움직이는 객체의 분할에 관한 연구)

  • 정철곤;김중규
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.27 no.3A
    • /
    • pp.221-230
    • /
    • 2002
  • This paper presents a new moving object segmentation algorithm using markov random field. The algorithm is based on signal detection theory. That is to say, motion of moving object is decided by binary decision rule, and false decision is corrected by markov random field model. The procedure toward complete segmentation consists of two steps: motion detection and object segmentation. First, motion detection decides the presence of motion on velocity vector by binary decision rule. And velocity vector is generated by optical flow. Second, object segmentation cancels noise by Bayes rule. Experimental results demonstrate the efficiency of the presented method.

SOME SMALL DEVIATION THEOREMS FOR ARBITRARY RANDOM FIELDS WITH RESPECT TO BINOMIAL DISTRIBUTIONS INDEXED BY AN INFINITE TREE ON GENERALIZED RANDOM SELECTION SYSTEMS

  • LI, FANG;WANG, KANGKANG
    • Journal of applied mathematics & informatics
    • /
    • v.33 no.5_6
    • /
    • pp.517-530
    • /
    • 2015
  • In this paper, we establish a class of strong limit theorems, represented by inequalities, for the arbitrary random field with respect to the product binomial distributions indexed by the infinite tree on the generalized random selection system by constructing the consistent distri-bution and a nonnegative martingale with pure analytical methods. As corollaries, some limit properties for the Markov chain field with respect to the binomial distributions indexed by the infinite tree on the generalized random selection system are studied.

A study on the relation between stationarity and synthesized images for GMRF (GMRF 모델의 안정성과 합성 영상과의 관계에 관한 연구)

  • 김성이;최윤식
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.34S no.2
    • /
    • pp.71-78
    • /
    • 1997
  • Markov random field models have extensively used in applications such as image segmentation and image restoration. In this paper, we consider the relation between the stationarity of parameters and the synthesized images for gauss-markov rnadom field which has the most popularly used among many MRF models. GMRF model, which is both wide-sense Markov and strict-sense markov, has AR representations and is also a kind of gibbs distribution. Therefore, we may approach in aspect of both AR models and gibbs models. We show the relation between the stationarity of parameters and the images which are synthesized by two approaching methods and derive the stationary regions of parameters in 1st order and isotropic 2nd order case.

  • PDF

An EM Algorithm-Based Approach for Imputation of Pixel Values in Color Image (색조영상에서 랜덤결측화소값 대체를 위한 EM 알고리즘 기반 기법)

  • Kim, Seung-Gu
    • The Korean Journal of Applied Statistics
    • /
    • v.23 no.2
    • /
    • pp.305-315
    • /
    • 2010
  • In this paper, a frequentistic approach to impute the values of R, G, B-components in random missing pixels of color image is provided. Under assumption that the given image is a realization of Gaussian Markov random field, its model is designed such that each neighbor pixel values for a given pixel follows (independently) the normal distribution with covariance matrix scaled by an evaluates of the similarity between two pixel values, so that the imputation is not to be affected by the neighbors with different color. An approximate EM-based algorithm maximizing the underlying likelihood is implemented to estimate the parameters and to impute the missing pixel values. Some experiments are presented to show its effectiveness through performance comparison with a popular interpolation method.