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[Author] Hao XU(11hit)

1-11hit
  • Adaptive Updating Probabilistic Model for Visual Tracking

    Kai FANG  Shuoyan LIU  Chunjie XU  Hao XUE  

     
    LETTER-Pattern Recognition

      Pubricized:
    2017/01/06
      Vol:
    E100-D No:4
      Page(s):
    914-917

    In this paper, an adaptive updating probabilistic model is proposed to track an object in real-world environment that includes motion blur, illumination changes, pose variations, and occlusions. This model adaptively updates tracker with the searching and updating process. The searching process focuses on how to learn appropriate tracker and updating process aims to correct it as a robust and efficient tracker in unconstrained real-world environments. Specifically, according to various changes in an object's appearance and recent probability matrix (TPM), tracker probability is achieved in Expectation-Maximization (EM) manner. When the tracking in each frame is completed, the estimated object's state is obtained and then fed into update current TPM and tracker probability via running EM in a similar manner. The highest tracker probability denotes the object location in every frame. The experimental result demonstrates that our method tracks targets accurately and robustly in the real-world tracking environments.

  • Adaptive-Partial Template Update with Center-Shifting Recovery for High Frame Rate and Ultra-Low Delay Deformation Matching

    Songlin DU  Yuhao XU  Tingting HU  Takeshi IKENAGA  

     
    PAPER-Image

      Vol:
    E102-A No:12
      Page(s):
    1872-1881

    High frame rate and ultra-low delay matching system plays an important role in various human-machine interactive applications, which demands better performance in matching deformable and out-of-plane rotating objects. Although many algorithms have been proposed for deformation tracking and matching, few of them are suitable for hardware implementation due to complicated operations and large time consumption. This paper proposes a hardware-oriented template update and recovery method for high frame rate and ultra-low delay deformation matching system. In the proposed method, the new template is generated in real time by partially updating the template descriptor and adding new keypoints simultaneously with the matching process in pixels (proposal #1), which avoids the large inter-frame delay. The size and shape of region of interest (ROI) are made flexible and the Hamming threshold used for brute-force matching is adjusted according to pixel position and the flexible ROI (proposal #2), which solves the problem of template drift. The template is recovered by the previous one with a relative center-shifting vector when it is judged as lost via region-wise difference check (proposal #3). Evaluation results indicate that the proposed method successfully achieves the real-time processing of 784fps at the resolution of 640×480 on field-programmable gate array (FPGA), with a delay of 0.808ms/frame, as well as achieves satisfactory deformation matching results in comparison with other general methods.

  • Altered Fingerprints Detection Based on Deep Feature Fusion

    Chao XU  Yunfeng YAN  Lehangyu YANG  Sheng LI  Guorui FENG  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2022/06/13
      Vol:
    E105-D No:9
      Page(s):
    1647-1651

    The altered fingerprints help criminals escape from police and cause great harm to the society. In this letter, an altered fingerprint detection method is proposed. The method is constructed by two deep convolutional neural networks to train the time-domain and frequency-domain features. A spectral attention module is added to connect two networks. After the extraction network, a feature fusion module is then used to exploit relationship of two network features. We make ablation experiments and add the module proposed in some popular architectures. Results show the proposed method can improve the performance of altered fingerprint detection compared with the recent neural networks.

  • Sorted Sector Covering Combined with Image Condensation -- An Efficient Method for Local Dimming of Direct-Lit and Edge-Lit LCDs Open Access

    Marc ALBRECHT  Andreas KARRENBAUER  Tobias JUNG  Chihao XU  

     
    INVITED PAPER

      Vol:
    E93-C No:11
      Page(s):
    1556-1563

    We consider the backlight calculation of local dimming as an optimization problem. The luminance produced by many LEDs at each pixel considered is calculated which should cover the gray value of each pixel, while the sum of LED currents is to be minimized. For this purpose a specific approach called as "Sorted Sector Covering" (SSC) was developed and is described in this paper. In our pre-processing unit called condenser the source image is reduced to a matrix of much lower resolution so that the computation effort of the SSC algorithm is drastically reduced. During this preprocessing phase, filter functions can be integrated so that a further reduction of the power consumption is achieved. Our processing system allows high power saving and high visual quality at low processor cost. We approach the local dimming problem in the physical viewing direction -- from LED to pixel. The luminance for the pixel is based on the light spread function (LSF) and the PWM values of the LEDs. As the physical viewing direction is chosen, this method is universal and can be applied for any kind of LED arrangement -- direct-lit as well as edge-lit. It is validated on prototypes, e.g., a locally dimmed edge-lit TV.

  • Multi-Autonomous Robot Enhanced Ad-Hoc Network under Uncertain and Vulnerable Environment Open Access

    Ming FENG  Lijun QIAN  Hao XU  

     
    INVITED PAPER

      Pubricized:
    2019/04/26
      Vol:
    E102-B No:10
      Page(s):
    1925-1932

    This paper studies the problem of real-time routing in a multi-autonomous robot enhanced network at uncertain and vulnerable tactical edge. Recent network protocols, such as opportunistic mobile network routing protocols, engaged social network in communication network that can increase the interoperability by using social mobility and opportunistic carry and forward routing algorithms. However, in practical harsh environment such as a battlefield, the uncertainty of social mobility and complexity of vulnerable environment due to unpredictable physical and cyber-attacks from enemy, would seriously affect the effectiveness and practicality of these emerging network protocols. This paper presents a GT-SaRE-MANET (Game Theoretic Situation-aware Robot Enhanced Mobile Ad-hoc Network) routing protocol that adopt the online reinforcement learning technique to supervise the mobility of multi-robots as well as handle the uncertainty and potential physical and cyber attack at tactical edge. Firstly, a set of game theoretic mission oriented metrics has been introduced to describe the interrelation among network quality, multi-robot mobility as well as potential attacking activities. Then, a distributed multi-agent game theoretic reinforcement learning algorithm has been developed. It will not only optimize GT-SaRE-MANET routing protocol and the mobility of multi-robots online, but also effectively avoid the physical and/or cyber-attacks from enemy by using the game theoretic mission oriented metrics. The effectiveness of proposed design has been demonstrated through computer aided simulations and hardware experiments.

  • Automatic and Accurate 3D Measurement Based on RGBD Saliency Detection

    Yibo JIANG  Hui BI  Hui LI  Zhihao XU  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2018/12/21
      Vol:
    E102-D No:3
      Page(s):
    688-689

    The 3D measurement is widely required in modern industries. In this letter, a method based on the RGBD saliency detection with depth range adjusting (RGBD-DRA) is proposed for 3D measurement. By using superpixels and prior maps, RGBD saliency detection is utilized to detect and measure the target object automatically Meanwhile, the proposed depth range adjusting is processing while measuring to prompt the measuring accuracy further. The experimental results demonstrate the proposed method automatic and accurate, with 3 mm and 3.77% maximum deviation value and rate, respectively.

  • An Algorithm of Connecting Broken Objects Based on the Skeletons

    Chao XU  Dongxiang ZHOU  Yunhui LIU  

     
    LETTER-Pattern Recognition

      Pubricized:
    2016/08/10
      Vol:
    E99-D No:11
      Page(s):
    2832-2835

    The segmentation of Mycobacterium tuberculosis images forms the basis for the computer-aided diagnosis of tuberculosis. The segmented objects are often broken due to the low-contrast objects and the limits of segmentation method. This will result in decreasing the accuracy of segmentation and recognition. A simple and effective post-processing method is proposed to connect the broken objects. The broken objects in the segmented binary images are connected based on the information obtained from their skeletons. Experimental results demonstrate the effectiveness of our proposed method.

  • Contrast Enhancement of Mycobacterium Tuberculosis Images Based on Improved Histogram Equalization

    Chao XU  Dongxiang ZHOU  Keju PENG  Weihong FAN  Yunhui LIU  

     
    LETTER-Biological Engineering

      Pubricized:
    2016/07/27
      Vol:
    E99-D No:11
      Page(s):
    2847-2850

    There are often low contrast Mycobacterium tuberculosis (MTB) objects in the MTB images. Based on improved histogram equalization (HE), a framework of contrast enhancement is proposed to increase the contrast of MTB images. Our proposed algorithm was compared with the traditional HE and the weighted thresholded HE. The experimental results demonstrate that our proposed algorithm has better performance in contrast enhancement, artifacts suppression, and brightness preserving for MTB images.

  • Automatic Recognition of Mycobacterium Tuberculosis Based on Active Shape Model

    Chao XU  Dongxiang ZHOU  Tao GUAN  Yongping ZHAI  Yunhui LIU  

     
    PAPER-Pattern Recognition

      Pubricized:
    2016/01/08
      Vol:
    E99-D No:4
      Page(s):
    1162-1171

    This paper realized the automatic recognition of Mycobacterium tuberculosis in Ziehl-Neelsen stained images by the conventional light microscopy, which can be used in the computer-aided diagnosis of the tuberculosis. We proposed a novel recognition method based on active shape model. First, the candidate bacillus objects are segmented by a method of marker-based watershed transform. Next, a point distribution model of the object shape is proposed to label the landmarks on the object automatically. Then the active shape model is performed after aligning the training set with a weight matrix. The deformation regulation of the object shape is discovered and successfully applied in recognition without using geometric and other commonly used features. During this process, a width consistency constraint is combined with the shape parameter to improve the accuracy of the recognition. Experimental results demonstrate that the proposed method yields high accuracy in the images with different background colors. The recognition accuracy in object level and image level are 92.37% and 97.91% respectively.

  • Silicon Controlled Rectifier Based Partially Depleted SOI ESD Protection Device for High Voltage Application

    Yibo JIANG  Hui BI  Hui LI  Zhihao XU  Cheng SHI  

     
    BRIEF PAPER-Semiconductor Materials and Devices

      Pubricized:
    2019/10/09
      Vol:
    E103-C No:4
      Page(s):
    191-193

    In partially depleted SOI (PD-SOI) technology, the SCR-based protection device is desired due to its relatively high robustness, but be restricted to use because of its inherent low holding voltage (Vh) and high triggering voltage (Vt1). In this paper, the body-tie side triggering diode inserting silicon controlled rectifier (BSTDISCR) is proposed and verified in 180 nm PD-SOI technology. Compared to the other devices in the same process and other related works, the BSTDISCR presents as a robust and latchup-immune PD-SOI ESD protection device, with appropriate Vt1 of 6.3 V, high Vh of 4.2 V, high normalized second breakdown current (It2), which indicates the ESD protection robustness, of 13.3 mA/µm, low normalized parasitic capacitance of 0.74 fF/µm.

  • Deformable Part-Based Model Transfer for Object Detection

    Zhiwei RUAN  Guijin WANG  Xinggang LIN  Jing-Hao XUE  Yong JIANG  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E97-D No:5
      Page(s):
    1394-1397

    The transfer of prior knowledge from source domains can improve the performance of learning when the training data in a target domain are insufficient. In this paper we propose a new strategy to transfer deformable part models (DPMs) for object detection, using offline-trained auxiliary DPMs of similar categories as source models to improve the performance of the target object detector. A DPM presents an object by using a root filter and several part filters. We use these filters of the auxiliary DPMs as prior knowledge and adapt the filters to the target object. With a latent transfer learning method, appropriate local features are extracted for the transfer of part filters. Our experiments demonstrate that this strategy can lead to a detector superior to some state-of-the-art methods.