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201-220hit(332hit)

  • Parameter Embedding in Motion-JPEG2000 through ROI for Variable-Coefficient Invertible Deinterlacing

    Jun UCHITA  Shogo MURAMATSU  Takuma ISHIDA  Hisakazu KIKUCHI  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E89-D No:11
      Page(s):
    2794-2801

    In this paper, a coefficient-parameter embedding method into Motion-JPEG2000 (MJP2) is proposed for invertible deinterlacing with variable coefficients. Invertible deinterlacing, which the authors have developed before, can be used as a preprocess of frame-based motion picture codec, such as MJP2, for interlaced videos. When the conventional field-interleaving is used instead, comb-tooth artifacts appear around edges of moving objects. On the other hand, the invertible deinterlacing technique allows us to suppress the comb-tooth artifacts and also guaranties recovery of original pictures. As previous works, the authors have developed a variable coefficient scheme with a motion detector, which realizes adaptability to local characteristics of given pictures. However, when this deinterlacing technique is applied to a video codec, coefficient parameters have to be sent to receivers for original picture recovery. This paper proposes a parameter-embedding technique in MJP2 and constructs a standard stream which consists both of picture data and the parameters. The parameters are embedded into the LH1 component of wavelet transform domain through the ROI (region of interest) function of JPEG2000 without significant loss in the performance of comb-tooth suppression. Some experimental results show the feasibility of our proposed scheme.

  • Compression Gain Measurements Using ROI-Based Data Reduction

    Hyungkeuk LEE  Sanghoon LEE  

     
    LETTER

      Vol:
    E89-A No:11
      Page(s):
    2985-2989

    For mobile visual communications, the development of more robust and efficient video traffic control and transmission techniques remains one of the most important issues. Foveated video originates from visual entropy reduction by removing undetectable high visual frequencies that occur at a distance from the fixation point. In this paper, compression gain is defined and measured to quantify the enhanced performance when the visual throughput of the regions of interest (ROI) is increased over a capacity-limited channel.

  • Prioritized Transmission Gain for Mobile Visual Communications

    Hyungkeuk LEE  Sanghoon LEE  

     
    LETTER

      Vol:
    E89-B No:10
      Page(s):
    2809-2812

    For point-to-point mobile visual communications, layered video has been utilized to adapt to time-varying channel capacity over noisy environments. From the perspective of the HVS (Human Visual System), it is necessary to minimize the loss of visual quality by specifically maintaining the throughput of visually important regions, objects and so on. Utilizing the prioritized bitstreams generated according to each layer, the throughput can be improved for given channel statistics. In this paper, we define the transmission gain and measure the improved performance when the throughput of ROI (Regions Of Interest) is increased relative to visually unimportant regions over a capacity limited mobile channel.

  • Traffic Engineering for Provisioning Restorable Hose-Model VPNs

    Yu-Liang LIU  Yeali Sunny SUN  Meng Chang CHEN  

     
    PAPER

      Vol:
    E89-B No:9
      Page(s):
    2394-2403

    Virtual Private Networks (VPNs) are overlay networks established on top of a public network backbone with the goal of providing a service comparable to Private Networks (PNs). The recently proposed VPN hose-model provides customers with flexible and convenient ways to specify their bandwidth requirements. To meet the specified bandwidth requirements, the Network Service Provider (NSP) must reserve sufficient bandwidth on the data transmission paths between each pair of endpoints in a VPN. In addition, the reliability of a VPN depends on the reliability of the data transmission paths. Italiano et al. proposed an algorithm that finds a set of backup paths for a given VPN (VPN tree) under the single-link failure model [1]. When a link failure is detected on a VPN tree, a backup path corresponding to the failed link can be activated to restore the disconnected VPN tree into a new one, thereby ensuring the reliability of the VPN. However, Italiano's algorithm cannot guarantee that the specified bandwidth requirement of the given VPN under the single-link failure model will be met. To address this issue, we propose a new backup path set selection algorithm called BANGUAD in this paper. In addition, the problem of establishing multiple bandwidth-guaranteed hose-model VPNs under the single-link failure model has not been investigated previously. However in this problem, bandwidth-sharing algorithms have the potential to improve the performance of a provisioning algorithm significantly. Therefore, we also propose a bandwidth sharing algorithm and three provisioning algorithms for establishing multiple bandwidth-guaranteed hose-model VPNs under the single-link failure model. Simulations that compare the performance of the proposed algorithms are reported.

  • Fast K Nearest Neighbors Search Algorithm Based on Wavelet Transform

    Yu-Long QIAO  Zhe-Ming LU  Sheng-He SUN  

     
    LETTER-Vision

      Vol:
    E89-A No:8
      Page(s):
    2239-2243

    This letter proposes a fast k nearest neighbors search algorithm based on the wavelet transform. This technique exploits the important information of the approximation coefficients of the transform coefficient vector, from which we obtain two crucial inequalities that can be used to reject those vectors for which it is impossible to be k nearest neighbors. The computational complexity for searching for k nearest neighbors can be largely reduced. Experimental results on texture classification verify the effectiveness of our algorithm.

  • Removal of Adherent Waterdrops from Images Acquired with a Stereo Camera System

    Yuu TANAKA  Atsushi YAMASHITA  Toru KANEKO  Kenjiro T. MIURA  

     
    PAPER-Stereo and Multiple View Analysis

      Vol:
    E89-D No:7
      Page(s):
    2021-2027

    In this paper, we propose a new method that can remove view-disturbing noises from stereo images. One of the thorny problems in outdoor surveillance by a camera is that adherent noises such as waterdrops on the protecting glass surface lens disturb the view from the camera. Therefore, we propose a method for removing adherent noises from stereo images taken with a stereo camera system. Our method is based on the stereo measurement and utilizes disparities between stereo image pair. Positions of noises in images can be detected by comparing disparities measured from stereo images with the distance between the stereo camera system and the glass surface. True disparities of image regions hidden by noises can be estimated from the property that disparities are generally similar with those around noises. Finally, we can remove noises from images by replacing the above regions with textures of corresponding image regions obtained by the disparity referring. Experimental results show the effectiveness of the proposed method.

  • A Hybrid Decimal Division Algorithm Reducing Computational Iterations

    Yong-Dae KIM  Soon-Youl KWON  Seon-Kyoung HAN  Kyoung-Rok CHO  Younggap YOU  

     
    PAPER-Numerical Analysis and Optimization

      Vol:
    E89-A No:6
      Page(s):
    1807-1812

    This paper presents a hybrid decimal division algorithm to improve division speed. The proposed hybrid algorithm employs either non-restoring or restoring algorithm on each digit to reduce iterative computations. The selection of the algorithm is based on the relative remainder values with respect to the half of its divisor. The proposed algorithm requires maximum 7n+4 add/subtract operations for an n-digit quotient, whereas other restoring or non-restoring schemes comprise more than 10n+1 operations.

  • A New Question Answering System for Chinese Restricted Domain

    Haiqing HU  Peilin JIANG  Fuji REN  Shingo KUROIWA  

     
    PAPER-Language

      Vol:
    E89-D No:6
      Page(s):
    1848-1859

    In this paper, we propose the construction of a web-based Question Answering (QA) system for restricted domain, which combines three resource information databases for the retrieval mechanism, including a Question&Answer database, a special domain documents database and the web resource retrieved by Google search engine. We describe a new retrieval technique of integrating a probabilistic technique based on OkapiBM25 and a semantic analysis which based on the ontology of HowNet knowledge base and a special domain HowNet created for the restricted domain. Furthermore, we provide a method of question expansion by computing word semantic similarity. The system is first developed for a middle-size domain of sightseeing information. The experiments proved the efficiency of our method for restricted domain and it is feasible to transfer to other domains expediently using the proposed method.

  • A Block Smoothing-Based Method for Flicker Removal in Image Sequences

    Lei ZHOU  Qiang NI  Yuanhua ZHOU  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E89-D No:4
      Page(s):
    1578-1581

    An automatic and efficient algorithm for removal of intensity flicker is proposed. The novel repair process is founded on the block-based estimation and restoration algorithm with regard to luminance variation. It is easily realized and controlled to remove most intensity flicker and preserve the wanted effects, like fade in and fade out.

  • Teeth Image Recognition for Biometrics

    Tae-Woo KIM  Tae-Kyung CHO  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E89-D No:3
      Page(s):
    1309-1313

    This paper presents a personal identification method based on BMME and LDA for images acquired at anterior and posterior occlusion expression of teeth. The method consists of teeth region extraction, BMME, and pattern recognition for the images acquired at the anterior and posterior occlusion state of teeth. Two occlusions can provide consistent teeth appearance in images and BMME can reduce matching error in pattern recognition. Using teeth images can be beneficial in recognition because teeth, rigid objects, cannot be deformed at the moment of image acquisition. In the experiments, the algorithm was successful in teeth recognition for personal identification for 20 people, which encouraged our method to be able to contribute to multi-modal authentication systems.

  • Signaling Overhead Analysis of Distributed Control for Partition-Based Protection in WDM Mesh Networks

    Chen-Shie HO  Sy-Yen KUO  

     
    PAPER-Network Protocols, Topology and Fault Tolerance

      Vol:
    E89-D No:2
      Page(s):
    728-737

    While the survivability becomes more and more important in WDM backbone network design, the signaling strategy corresponding to a protection/restoration scenario upon failures will have significant influence on the performance and then determine the integrity of the total solution. In this paper we will discuss the control mechanisms for several representative protection schemes, analyze their adaptation and application, and propose the corresponding signaling model and control protocol for a novel dynamic group protection strategy. The simulation results show that the control overhead of our proposed method outperforms the segmented protection and has the benefit on resource utilization and failure restoration speed.

  • A Class of Two-Dimensional Signal Having a Flat Power Spectrum and a Low Peak Factor

    Takafumi HAYASHI  

     
    PAPER-Digital Signal Processing

      Vol:
    E89-A No:2
      Page(s):
    494-502

    This paper presents a new generative approach for generating two-dimensional signals having both a low peak factor (crest factor) and a flat power spectrum. The flat power spectrum provides zero auto-correlation, except at the zero shift. The proposed method is a generative scheme, not a search method, and produces a two-dimensional signal of size 2(2n1+1)2(2n2+1)2 for an arbitrary pair of positive integers n1 and n2 without any computer search. The peak factor of the proposed signal is equal to the peak factor of a single trigonometric function.

  • Variable Frame Skipping Scheme Based on Estimated Quality of Non-coded Frames at Decoder for Real-Time Video Coding

    Tien-Ying KUO  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E88-D No:12
      Page(s):
    2849-2856

    This paper proposes a block-based video encoder employing variable frame skipping (VFS) to improve the video quality in low bit rate channel. The basic idea of VFS mechanism is to decide and skip a suitable, non-fixed number of frames in temporal domain to reduce bit usage. The saved bits can be allocated to enhance the spatial quality of video. In literature, several methods of frame skipping decision have been proposed, but most of them only consider the similarities between neighboring coded frames as the decision criteria. Our proposed method takes into account the reconstruction of the skipped frames using motion-compensated frame interpolation at decoder. The proposed VFS models the reconstructed objective quality of the skipped frame and, therefore, can provide a fast estimate to the frame skipping at encoder. The proposed VFS can determine the suitable frame skipping in real time and provide the encoded video with better spatial-temporal bit allocation.

  • Optimal Sampling Operator for Signal Restoration in the Presence of Signal Space and Observation Space Noises

    Aqeel SYED  Hidemitsu OGAWA  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E88-D No:12
      Page(s):
    2828-2838

    The partial projection filter (PTPF) for a given observation operator provides an optimal signal restoration in the presence of both the signal space and observation space noises. However, restoration error by the filter still depends on the observation operator which consists of measurement and sampling processes. In this paper, we determine a sampling operator which minimizes the restoration error by the PTPF. We see that under some assumptions about noise statistics, the restoration error by the PTPF is divided into two terms corresponding to the error arising from the signal space noise and that from the observation space noise. It has been found that although the restoration error due to the signal space noise is independent of the sampling operator, the restoration error arising from the observation space noise can arbitrarily be decreased by increasing the number of sample points in the proposed sampling operator. An illustrative example of optimal sampling in the trigonometric polynomial space is also given.

  • Semi-Dynamic Protection Path Configuration for Hybrid Optical Cross-Connect Networks

    Hoyoung HWANG  

     
    PAPER

      Vol:
    E88-B No:10
      Page(s):
    3922-3929

    In this paper, a semi-dynamic protection path configuration method is proposed for WDM optical networks. In the method, the protection path is established by connecting several sub-lightpaths from the source node to the destination node of the original working lightpath, as opposed to conventional path restoration method where a single protection lightpath between the source-destination pair performs restoration. The proposed method provides enhanced flexibility in protection path configuration and relieves the cost of spare capacity reservation. This paper also studies the effects of wavelength conversion capability of intermediate optical cross-connect nodes on protection path routing and spare capacity utilization. In terms of spare capacity utilization, the proposed method shows substantial reduction of spare capacity overhead compared with dedicated path restoration in all optical networks without wavelength conversion, and shows similar capacity efficiency compared with shared path restoration in opaque networks with full wavelength conversion capability. In terms of robustness, the proposed method shows nearly the same restoration ratio for double-link failure as that of dynamic restoration method.

  • Highly-Reliable and Fast M:N End-to-End Restoration Scheme for Photonic IP Networks

    Wataru IMAJUKU  Yoshiaki SONE  Naohide NAGATSU  Akio SAHARA  Yoshihiro TAKIGAWA  

     
    PAPER

      Vol:
    E88-B No:10
      Page(s):
    3914-3921

    The concept of an optical path layer has become increasingly attractive with the growth of traffic in the backbone network. The recent advances in optical switching technology support the deployment of optical cross-connect (OXC) nodes and the construction of large-scale optical path networks. This paper proposes a highly-reliable and fast pre-assigned restoration scheme for optical path networks. To achieve the pre-assigned restoration scheme, this paper investigates the extension of the Generalized Multi-Protocol Label Switching (GMPLS) protocol functionality considering the interoperability with GMPLS capable IP routers in the future. This paper also proposes a new network control architecture called the "partition model" through discussion of network architecture. We clarify that the M:N end-to-end restoration scheme achieves efficient resource usage and management of the network especially in the "partitioned model" network. With the finite design of the GMPLS protocol extension based on the M:N end-to-end restoration scheme, we successfully achieve an intelligent protocol that guarantees 100% recovery against single link failure and is capable of protection grade fast restoration of the optical path less than 50 msec. To our knowledge, this is the first demonstration of GMPLS-controlled protection grade fast optical path restoration.

  • A Distributed Route Computation Method to Promote Bandwidth Sharing between Backup Lightpaths

    Nagao OGINO  Hideaki TANAKA  

     
    PAPER

      Vol:
    E88-B No:10
      Page(s):
    3930-3940

    The optical network is a promising approach for realizing a scalable backbone network. In backbone networks, survivability is very important because great volumes of traffic incur damage from faulty equipment. To address this issue, various recovery schemes have been proposed for optical backbone networks. Among those schemes, shared mesh restoration utilizes link bandwidth efficiently because the backup lightpaths share link bandwidth if they protect against different failures and are never utilized simultaneously. However, a route computation method for the backup lightpaths that promotes such bandwidth sharing is necessary to achieve efficient bandwidth utilization. This paper proposes a distributed route computation method for the backup lightpaths in shared mesh restoration. In this method, the link weight is estimated to be smaller if a backup lightpath newly established can share the link bandwidth with the backup lightpaths already accommodated in that link. The link weight can be calculated using the Markov Decision Theory. The bandwidth sharing between the backup lightpaths can be promoted by selecting the shortest route based on such modified link weights. The proposed method effectively realizes efficient utilization of the link bandwidth and achieves low loss rate of reliable lightpath establishment requests under the same traffic load. The proposed method restricts the amount of link state information advertised by the routing protocol and achieves a sufficiently small amount of route calculation.

  • A Spatiotemporal Neuronal Filter for Channel Equalization and Video Restoration

    Elhassane IBNELHAJ  Driss ABOUTAJDINE  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E88-D No:10
      Page(s):
    2427-2431

    In this paper we present a 3D adaptive nonlinear filter, namely the 3D adaptive CPWLN, based on the Canonical Piece Wise-Linear Network with an LMS L-filter type of adaptation. This filter is used to equalize nonlinear channel effect and remove impulsive/or mixed impulsive and Additive White Gaussian noise from video sequences. First, motion compensation is performed by a robust estimator. Then, a 3-D CPWLN LMS L-filter is applied. The overall combination is able to adequately remove undesired effects of communication channel and noise. Computer simulations on real-world image sequences are included. The algorithm yields promising results in terms of both objective and subjective quality of the restored sequence.

  • Study of On-Glass Mobile Antennas for Digital Terrestrial Television

    Shin-ichiro MATSUZAWA  Kazuo SATO  Kunitoshi NISHIKAWA  

     
    LETTER-Antennas and Propagation

      Vol:
    E88-B No:7
      Page(s):
    3094-3096

    Digital Terrestrial Television (DTV) services began in Japan in December 2003. This paper proposes a novel on-glass antenna for mobile reception of terrestrial television. The gain of the proposed antenna is 4.7 dB higher than commercial monopole antennas when installed on a vehicle. Other merits of this antenna are a broad input impedance bandwidth across the UHF band (470-710 MHz), and the fact that it does not spoil vehicle appearance. Field experiments have confirmed that a diversity system using four of the proposed antennas is capable of mobile DTV reception.

  • A Visual Attention Based Region-of-Interest Determination Framework for Video Sequences

    Wen-Huang CHENG  Wei-Ta CHU  Ja-Ling WU  

     
    PAPER-Image Processing and Multimedia Systems

      Vol:
    E88-D No:7
      Page(s):
    1578-1586

    This paper presents a framework for automatic video region-of-interest determination based on visual attention model. We view this work as a preliminary step towards the solution of high-level semantic video analysis. Facing such a challenging issue, in this work, a set of attempts on using video attention features and knowledge of computational media aesthetics are made. The three types of visual attention features we used are intensity, color, and motion. Referring to aesthetic principles, these features are combined according to camera motion types on the basis of a new proposed video analysis unit, frame-segment. We conduct subjective experiments on several kinds of video data and demonstrate the effectiveness of the proposed framework.

201-220hit(332hit)