SMAPIP


Grant-in-Aid for Scientific Research on Priority Areas
``Statistical Mechanical Approach to Probabilistic Information Processing''

Research Project C02:
Design of Adaptive Filters for Image Processing
by means of Markov Random Field Models


[Japanese Version]

Project Leader:
Kazuyuki Takana

Graduate School of Information Sciences, Tohoku University (Japan)

Address, Phone, E-mail address:

  • Address: Graduate School of Information Sciences, Tohoku University,
    Aramaki-Aza-Aoba 6-3-09, Aoba-ku, Sendai 980-8579, Japan
  • Phone: +81-22-795-5885, E-mail: kazu [at mark] smapip.is.tohoku.ac.jp
  • Office: Room No.403 in Research Building No.3 - Electrical, Information and Physics Engineering, Aobayama Campus, Tohoku University


    1. What is an image restoration?

        Let us consider that an original image is degraded by adding a noise. It is the image restoration that the original image is estimated from the degraded image.

      Design of Image processing filter and theory of magnetic material.

        Some probabilistic models proposed to investigate the properties of magnetic material can be applied to design image processing filters. Why is it possible?

          Image processing and magnetic material have two similar theoretical structures with each other. The similarities are very simple. They are constructed from many elements. The many elements interact with each other. As you know, the classical spin systems have a lot of spins and each spin interacts with the neighboring spins. The ordered state is determined from interactions and external fields. On the other hand, images are constructed from a lot of pixels. Output of each pixel are determined from the input values of the neighboring pixels. Output images are determined from a priori information and given data. Thus, the conventional image processing theory and the classical spin system have the similar structure. In the classical spin system, the phase transition occurs at a critical temperature. Below the critical temperature, the classical spin system has a disordered state, for example Paramagnetic state. Above the critical temperature, the classical spin system has an ordered state, for example Ferromagnetic state. In statistical mechanics, many researchers investigate the classical spin systems near the critical temperature. Near the critical temperature, fluctuation is enhanced. Statistical mechanics has a lot of techniques to treat fluctuation near the critical temperature. On the other hand, it is difficult for conventional filters to treat fluctuation in data systematically. In the present project, the statistical mechanical strategies are employed to treat fluctuation in data in image processing.

        Image restirations by means of probabilistic models

          Binary image restiration (The noise is a binary symmetric channel; Loopy Belief Propagation)

          Original Image, Degraded Image and Restored Image by using Ising Model

             
            Kazuyuki Tanaka: Statistical-mechanical approach to image processing (Topical Review), Journal of Physics A: Mathematical and General, vol.35, no.37, pp.R81-R150, September 2002.

          Multi-valued image restoration (4-valued image; The noise is an extended version of binary symmetric channel; Loopy Belief Propagation)

          Original Image, Degraded Image and Restored Image by Potts Model

            Kazuyuki Tanaka: Theoretical Study of Hyperparameter Estimation by Maximization of Marginal Likelihood in Image Restoration by means of Cluster Variation Method, IEICE Transactions (A), Vol.J83-A, No.10 (October 2000), pp.1148-1160 (PDF file, in Japanese); translated in Electronics and Communications in Japan, Part 3: Fundamental Electronic Science, Vol.85, No.7 (July 2002) pp.50-62 (PDF File, in English).

          Multi-valued image restoration (4-valued image; The noise is an extended version of binary symmetric channel; Loopy Belief Propagation)

          Original Image, Degraded Image and Restored Image by Q-Ising Model

            Kazuyuki Tanaka, Jun-ichi Inoue and D. M. Titterington: Probabilistic image processing by means of Bethe approximation for Q-Ising model, Journal of Physics A: Mathematical and General, Vol. 36, No. 43 (October 2003), pp.11023-11036 (PDF File).

          Grey-level image restoration by using modified Potts model (256-valed Image; The noise is an extended version of binary symmetric channel; Loopy Belief Propagation)

          Original Image, Degraded Image and Restored Image by Modified Potts Model

               
            Kazuyuki Tanaka: Automatic Hyperparameter Estimation in Probabilistic Image Restoration Algorithm based on Gibbs Microcanonical Distribution. IEICE Transactions (D-II), Vol.J85-D-II, No.5 (May 2002), pp.815-824. (PDF File, in Japanese).

          Grey-level image restoration by Gaussian Graphical Model (256-valued image; The noise is an additive white Gaussian noise; Exact calculation by using multi-dimensional Gaussian integral formulas)

          Original Image, Degraded Image and Restored Image by Modified Gaussian Graphical Model

               
            Kazuyuki Tanaka and Jun-ichi Inoue: Maximum Likelihood Hyperparameter Estimation for Solvable Markov Random Field Model in Image Restoration, IEICE Transactions on Information and Systems, Vol.E85-D, No.3 (March 2002), pp.546-557 (PDF file).

          Color image restoration (256-valued image; The noise is an additive white Gaussian noise; Exact calculation by using multi-dimensional Gaussian integral formulas)

          Original Image, Degraded Image and Restored Image by Modified Gaussian Graphical Model

               
            Kazuyuki Tanaka and Tsuyoshi Horiguchi: Solvable Markov Random Field Model in Color Image Restoration, Phisical Review E, Vol.65, No.4 (April 2002), Article No.046142, pp.1-18 (PDF file, Postscript file).


      Contact: Kazuyuki Tanaka
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