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[Author] Hitoshi KITAZAWA(13hit)

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  • Extraction and Tracking Moving Objects in Detail Considering Visual Feature Constraint and Structure Constraint

    Zhu LI  Yoichi TOMIOKA  Hitoshi KITAZAWA  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E96-D No:5
      Page(s):
    1171-1181

    Detailed tracking is required for many vision applications. A visual feature-based constraint underlies most conventional motion estimation methods. For example, optical flow methods assume that the brightness of each pixel is constant in two consecutive frames. However, it is difficult to realize accurate extraction and tracking using only visual feature information, because viewpoint changes and inconsistent illumination cause the visual features of some regions of objects to appear different in consecutive frames. A structure-based constraint of objects is also necessary for tracking. In the proposed method, both visual feature matching and structure matching are formulated as a linear assignment problem and then integrated.

  • FOREWORD

    Masaharu IMAI  Hitoshi KITAZAWA  

     
    FOREWORD

      Vol:
    E81-A No:12
      Page(s):
    2475-2475
  • Robust Moving Object Extraction and Tracking Method Based on Matching Position Constraints

    Tetsuya OKUDA  Yoichi TOMIOKA  Hitoshi KITAZAWA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2015/04/28
      Vol:
    E98-D No:8
      Page(s):
    1571-1579

    Object extraction and tracking in a video image is basic technology for many applications, such as video surveillance and robot vision. Many moving object extraction and tracking methods have been proposed. However, they fail when the scenes include illumination change or light reflection. For tracking the moving object robustly, we should consider not only the RGB values of input images but also the shape information of the objects. If the objects' shapes do not change suddenly, matching positions on the cost matrix of exclusive block matching are located nearly on a line. We propose a method for obtaining the correspondence of feature points by imposing a matching position constraint induced by the shape constancy. We demonstrate experimentally that the proposed method achieves robust tracking in various environments.

  • A New Routing Method Considering Neighboring-Wire Capacitance Constraints

    Takumi WATANABE  Kimihiro YAMAKOSHI  Hitoshi KITAZAWA  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E81-A No:12
      Page(s):
    2679-2687

    This paper presents a new routing method that takes into account neighboring-wire-capacitance (inter-layer and intra-layer) constraints. Intermediate routing (IR) assigns each H/V wire segment to the detailed routing (DR) grid using global routing (GR) results, considering the neighboring-wire constraints (NWC) for critical nets. In DR, the results of IR for constrained nets and their neighboring wires are preserved, and violations that occur in IR are corrected. A simple method for setting NWC that satisfy the initial wire capacitance given in a set-wire-load (SWL) file is also presented. The routing method enables more accurate delay evaluation by considering inter-wire capacitance before DR, and avoids long and costly turnaround in deepsubmicron layout design. Experimental results using MCNC benchmark test data shows that the errors between the maximum delay from IR and that from DR for each net were less than 5% for long (long delay) nets.

  • Template Matching Method Based on Visual Feature Constraint and Structure Constraint

    Zhu LI  Kojiro TOMOTSUNE  Yoichi TOMIOKA  Hitoshi KITAZAWA  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E95-D No:8
      Page(s):
    2105-2115

    Template matching for image sequences captured with a moving camera is very important for several applications such as Robot Vision, SLAM, ITS, and video surveillance systems. However, it is difficult to realize accurate template matching using only visual feature information such as HSV histograms, edge histograms, HOG histograms, and SIFT features, because it is affected by several phenomena such as illumination change, viewpoint change, size change, and noise. In order to realize robust tracking, structure information such as the relative position of each part of the object should be considered. In this paper, we propose a method that considers both visual feature information and structure information. Experiments show that the proposed method realizes robust tracking and determine the relationships between object parts in the scenes and those in the template.

  • A Global Router Optimizing Timing and Area for High-Speed Bipolar LSIs

    Ikuo HARADA  Yuichiro TAKEI  Hitoshi KITAZAWA  

     
    PAPER

      Vol:
    E77-A No:12
      Page(s):
    2058-2066

    A timing-driven global routing algorithm is proposed that directly models the path-based timing constraints. By keeping track of the critical path delay and channel densities, and using novel heuristic criteria, it can select routing paths that minimize area as well as satisfy the timing constraints. Using bipolar-specific features, this router can be used to design LSI chips that handle signals with speeds greater that a gigabit per second. Experimental results shows an average delay improvement of 17.6%.

  • Exclusive Block Matching for Moving Object Extraction and Tracking

    Zhu LI  Kenichi YABUTA  Hitoshi KITAZAWA  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E93-D No:5
      Page(s):
    1263-1271

    Robust object tracking is required by many vision applications, and it will be useful for the motion analysis of moving object if we can not only track the object, but also make clear the corresponding relation of each part between consecutive frames. For this purpose, we propose a new method for moving object extraction and tracking based on the exclusive block matching. We build a cost matrix consisting of the similarities between the current frame's and the previous frame's blocks and obtain the corresponding relation by solving one-to-one matching as linear assignment problem. In addition, we can track the trajectory of occluded blocks by dealing with multi-frames simultaneously.

  • Power and Timing Optimization for ECL LSIs in Post-Layout Design

    Akira ONOZAWA  Hitoshi KITAZAWA  Kenji KAWAI  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E79-A No:6
      Page(s):
    892-899

    In this paper, a post-layout optimization technique for power dissipation and timing of cell-based Bipolar ECL LSIs is proposed. An ECL LSI can operate at a frequency of a few GHz but the power dissipation is very high compared to CMOS LSIs, which makes the systems using ECL quite expensive. Therefore it is crucial to develop of CAD techniques that minimize the power dissipation of an ECL LSI without decreasing its performance. To begin with, power and delay models of an ECL gate are presented as functions of its switching current. The power dissipation is a linear function of the switching current and the delay time is its hyperbolic function. These functions are obtained considering the post-layout interconnect capacitance and resistance to make the optimization results accurate enough. Using the delay model, a set of timing constraints specifying the max/min cell delay and the clock skew are extracted. This set of constraints in then given to a nonlinear programming package. The objective functions are clock skew time, the clock cycle time and the power dissipation, which are optimized in this order. With the minimum delay and hold constraints, the problem is not convex so that conventional convex programming approach cannot be used. As a result of the optimization, the switching currents for cells are obtained. These are realized within cells by regulating programmable resistors", which is a special feature of our ECL cell library. Since the above optimization is carried out after the placement and routing of the circuit, it can take accurate delay and power estimation into consideration. Experimental results show more than 40% power reductions for circuits including a real communication system chip, compared to the max power versions. The clock cycle time was maintained or even made faster due to the efficient clock skew optimization.

  • An FPGA Implementation of the Two-Dimensional FDTD Method and Its Performance Comparison with GPGPU

    Ryota TAKASU  Yoichi TOMIOKA  Yutaro ISHIGAKI  Ning LI  Tsugimichi SHIBATA  Mamoru NAKANISHI  Hitoshi KITAZAWA  

     
    PAPER

      Vol:
    E97-C No:7
      Page(s):
    697-706

    Electromagnetic field analysis is a time-consuming process, and a method involving the use of an FPGA accelerator is one of the attractive ways to accelerate the analysis; the other method involve the use of CPU and GPU. In this paper, we propose an FPGA accelerator dedicated for a two-dimensional finite-difference time-domain (FDTD) method. This accelerator is based on a two-dimensional single instruction multiple data (SIMD) array architecture. Each processing element (PE) is composed of a six-stage pipeline that is optimized for the FDTD method. Moreover, driving signal generation and impedance termination are also implemented in the hardware. We demonstrate that our accelerator is 11 times faster than existing FPGA accelerators and 9 times faster than parallel computing on the NVIDIA Tesla C2075. As an application of the high-speed FDTD accelerator, the design optimization of a waveguide is shown.

  • FPGA Implementation of Exclusive Block Matching for Robust Moving Object Extraction and Tracking

    Yoichi TOMIOKA  Ryota TAKASU  Takashi AOKI  Eiichi HOSOYA  Hitoshi KITAZAWA  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E97-D No:3
      Page(s):
    573-582

    Hardware acceleration is an essential technique for extracting and tracking moving objects in real time. It is desirable to design tracking algorithms such that they are applicable for parallel computations on hardware. Exclusive block matching methods are designed for hardware implementation, and they can realize detailed motion extraction as well as robust moving object tracking. In this study, we develop tracking hardware based on an exclusive block matching method on FPGA. This tracking hardware is based on a two-dimensional systolic array architecture, and can realize robust moving object extraction and tracking at more than 100 fps for QVGA images using the high parallelism of an exclusive block matching method, synchronous shift data transfer, and special circuits to accelerate searching the exclusive correspondence of blocks.

  • Privacy Protection by Masking Moving Objects for Security Cameras

    Kenichi YABUTA  Hitoshi KITAZAWA  Toshihisa TANAKA  

     
    PAPER-Image

      Vol:
    E92-A No:3
      Page(s):
    919-927

    Because of an increasing number of security cameras, it is crucial to establish a system that protects the privacy of objects in the recorded images. To this end, we propose a framework of image processing and data hiding for security monitoring and privacy protection. First, we state the requirements of the proposed monitoring systems and suggest possible implementation that satisfies those requirements. The underlying concept of our proposed framework is as follows: (1) in the recorded images, the objects whose privacy should be protected are deteriorated by appropriate image processing; (2) the original objects are encrypted and watermarked into the output image, which is encoded using an image compression standard; (3) real-time processing is performed such that no future frame is required to generate on output bitstream. It should be noted that in this framework, anyone can observe the decoded image that includes the deteriorated objects that are unrecognizable or invisible. On the other hand, for crime investigation, this system allows a limited number of users to observe the original objects by using a special viewer that decrypts and decodes the watermarked objects with a decoding password. Moreover, the special viewer allows us to select the objects to be decoded and displayed. We provide an implementation example, experimental results, and performance evaluations to support our proposed framework.

  • A Layout System for Mixed A/D Standard Cell LSI's

    Ikuo HARADA  Hitoshi KITAZAWA  Takao KANEKO  

     
    PAPER

      Vol:
    E75-C No:3
      Page(s):
    322-332

    A layout system for mixed analog/digital standard cell LSI's is described. The system includes interactive floorplan and placement features and automatic global and channel router. In mixed analog/digital circuits, crosstalk noise causes chip performance degradation. Thus, the proposed global routing algorithm routes analog nets in areas that are free of digital nets as much as possible. The number of line crossovers, especially for analog nets, is minimized by both global and detailed routers, because these crossovers are the dominant factors in the crosstalk noise. Double width lines can be used to avoid unexpected voltage drops caused by parasitic resistances. A postprocess automatically puts up shield lines for very noise sensitive wirings to improve the S/N ratio. Experimental results show that the proposed algorithms are effective in reducing the number of crossovers and redundant vias.

  • Sunshine-Change-Tolerant Moving Object Masking for Realizing both Privacy Protection and Video Surveillance

    Yoichi TOMIOKA  Hikaru MURAKAMI  Hitoshi KITAZAWA  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E97-D No:9
      Page(s):
    2483-2492

    Recently, video surveillance systems have been widely introduced in various places, and protecting the privacy of objects in the scene has been as important as ensuring security. Masking each moving object with a background subtraction method is an effective technique to protect its privacy. However, the background subtraction method is heavily affected by sunshine change, and a redundant masking by over-extraction is inevitable. Such superfluous masking disturbs the quality of video surveillance. In this paper, we propose a moving object masking method combining background subtraction and machine learning based on Real AdaBoost. This method can reduce the superfluous masking while maintaining the reliability of privacy protection. In the experiments, we demonstrate that the proposed method achieves about 78-94% accuracy for classifying superfluous masking regions and moving objects.