ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
22.8
Showing 1-20 articles out of 20 articles from the selected issue
  • Type: Cover
    Pages Cover1-
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Index
    Pages Toc1-
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Masato Tsukahara, Miki Haseyama, Hideo Kitajima
    Type: Article
    Pages 1-6
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Image coding for edge retention using adaptive KL transform is investigated. The pixel blocks are classified into subsets of blocks according to their edge contents and orientations. Five covariance matrices are calculated and five matrices of KL transform (adaptive KL transform) are designed for each class. In practice, images are separated into two frequency components, that are low and high frequency components. The DCT is used for image coding of the low frequency components. Adaptive KLT is used for edge images coding (high frequency components). The method for edge images coding is compared with a method using the DCT and the effectiveness of using adaptive KL transform is examined.
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  • Satoshi ASAMIZU, Miki HASEYAMA, Hideo KITAJIMA
    Type: Article
    Pages 7-12
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper proposes a motion model using a DCT for motion compensation based on table lookup. In this paper the coefficients of DCT finds from a movement of every pixel. It is decided that the number of the coefficients in IDCT. The proposed method represented motion that the coefficients of IDCT. The proposed method make a table using the coefficients of DCT number can be set up freely. Various motion patterns are put into a table. The motion compensation based on table lookup selects the motion to minimize prediction error from the table.
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  • Riichiroh Koike, Miki Haseyama, Hideo Kitajima
    Type: Article
    Pages 13-18
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper proposes multi-flame motion-compensated prediction using 3-D model. Motion-compensated prediction using 3-D model has much quantity of coding. The proposed method improves coding efficiency by using same parameter in multi-flame. Results of some experiments show to verify the effect of proposed method.
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  • Madoka HASEGAWA, Takeharu ADACHI, Shigeo KATO, Yoshifumi YAMADA
    Type: Article
    Pages 19-25
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper describes a partially decodable method using modified Golomb-Rice code. When an image of quite large size is represented in a display, the shrinked image or a part of the image are displayed. Many users often hope to view the desired part of the image with higher resolution by enlargement or to see the parts of the image outside of the displayed area by scrolling. In such cases, it is needed that any part of encoded bit stream can be decoded. That is to say, the code should be able to be decoded not only from the top of code sequence but also from any position. In our method, we realized the partially decodable coding method by using a special all 1 digits code of desired length for block detection.
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  • Kunitoshi KOMATSU, Kaoru SEZAKI
    Type: Article
    Pages 27-32
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In this paper, we propose one-dimentional reversible two-channel filter banks. Up to now, only reversible filter banks (reversible wavelet transforms) have been proposed which correspond to particular perfect reconstruction filters with (taps of lowpass filter)^*(taps of highpass filter) being 2^*2,1^*3,5^*3,2^*6. In this paper, we propose reversible filter banks which correspond to general perfect reconstruction filters with (2N)^*(2N), (2N+1)^*(2M+1). Firstly, reversible filter banks of 2^*2 and 1^*3 are shown and then various reversible filter banks are derived by combining them. The lossless and lossy compression efficiencies of the proposed method are compared with conventional methods in consideration of their application to unified lossless and lossy coding of still images. It is shown that compression efficiency of the proposed method is almost the same as conventional methods.
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  • Masayuki BABA, Yoshiaki KATO
    Type: Article
    Pages 33-40
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Recently MPEG-2 Transport Streams (TS) become widely use for digital broadcasting services. For switching programs or inserting advertisement between programs, the MPEG-2 TS 'splicing' technique which is prescribed in MPEG-2 standard will be used in the future. In this report, we examine realization methods of splicing based on MPEG-2 standard and its application. Especially we consider creation methods of TS suited for splicing and operation of splicing device. Furthermore we propose more useful splicing methods.
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  • Hatsuhito UENO, Ichiro MATSUDA, Susumu ITOH, Hiroyuki IMAIZUMI
    Type: Article
    Pages 41-46
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We previously proposed a new disparity compensation scheme using bilinear transform with variable-size-patches for stereo video coding. This paper describes performance of several evaluation parameters which are utilized for detecting disparity vectors. Simulation results indicate that energy of AC components of disparity compensated prediction error signals in each block composed of 8×8 pels where DCT is carried out is the best of the above parameters in terms of coding performance and computational load. In addition, incorporation of a coding rate of disparity vectors into the evaluation parameter as well as increase of kinds of patch-size can further improve coding performance.
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  • Kenichi WATANABE, Tetsuro NAGAE, Ichiro MATSUDA, Susumu ITOH
    Type: Article
    Pages 47-52
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper proposes a new region-oriented coding scheme of still images based on Voronoi diagrams. In this scheme, first an image is partitioned into Voronoi regions so that their boundaries can fit well the principal contours in the image. Then image signals in each Voronoi region are encoded using orthogonal transform. We introduce the hierarchical renewal method of positions of generators to improve performance of the segmentation. And the adaptive transform method which conducts one-dimensional DCT twice is utilized to reduce the amount of computation required for transform coding. Furthermore, this paper describes a technique which optimizes representative values of linear quantizers for DCT coefficients. Simulation results indicate that the proposed coding scheme achieves the almost same coding performance as the KLT-based scheme, although the former can remarkably reduce computational load compared with the latter.
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  • Kazunori KOTANI, Yoshiko FURUSHO, Yuukou HORITA, Makoto MIYAHARA
    Type: Article
    Pages 53-60
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper shows the picture quality model for an evaluation of JPEG coded color pictures based on human observing points and local feature of color pictures. The distortion models are consist of fundermental quality factors defined by color difference on CIE L^*a^*b^* color space. The equations of evaluation are obtaind by Multivariate Analysis of distortion models. This model evaluates the picture quality with high accuracy and estimates Mean Opinion Score well.
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  • Takao Ino, Yukio Kobayashi, Makoto Miyahara
    Type: Article
    Pages 61-66
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We are investigating the important physical factors for the reproduction of the high order artistic impression in a display of images. We have considered the deterioration of "image depth" caused by the nonlinear gamma. In this report, we have corrected a gamma to a constant value γ=3.0 which is inverse characteristic of the input system independent of signal level. As a result of an assessment test, the assessment on "image depth" is improved greatly and we have confirmed that gamma characteristic is important not only for the reproduction of "image depth" but for the reproduction of the high order sensation. For instance, the nobility of an reproduced images is greatly improved.
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  • Takao Ino, Hideki Shirai, Yukio Kobayashi, Makoto Miyahara, Shuji Tani ...
    Type: Article
    Pages 67-74
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We are investigating the important physical factors for the difficult reproduction of high order artistic impression in a display of images. We have found a key assessment word "image depth" describes appropriately the high order subjective sensation that is indispensable for the display of extra high quality images. Related to the depth of images, Cross modulation among R, G and B signals is the newly discovered important physical factor affecting the display quality. As a result of an assessment test, we have confirmed that the cross modulation characteristic deteriorates the image depth. We have defined the characteristic of cross modulation to guarantee "the color difference is smaller than 1". We have developed a display which satisfy the given characteristics.
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  • Takao Ino, Hideki Shirai, Yukio Kobayashi, Makoto Miyahara
    Type: Article
    Pages 75-80
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We are investigating the important physical factors for the reproduction of the high order artistic impression in a display of images. We have considered the deterioration of "image depth" caused by the aliasing generated by that the structure of phosphor of a CRT display. In this report, we have simulated the effect comparing the simulated images of the phosphor structure of the Aperture Grill type and the Shadow Mask type (dot trio). As a result of an assessment test, we have obtained that the Aperture Grill type destroy "image depth" than the Shadow Mask type (dot trio). The destruction is clear in paintings of landscapes which contains much information of the "image depth".
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  • Toshikazu Matsui
    Type: Article
    Pages 81-88
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Visual accommodative responses to multiple motion patterns are examined using an infrared optometer. The stimuli are compound waves (Fourier stimuli) consisting of two drifting sinusoidal waves with opposite motion directions and amplitude-modulated waves (non-Fourier stimuli) whose carrier and signal sinusoidal components move in opposite directions. Accommodative responses are measured while each component wave's motion is paid attention to. It is shown that there exist two kinds of accommodative states which accompany two kinds of motion appearance characteristics depending on which component wave's motion observers pay attention to, irrespective of the viewing distance, and that the degree of the retinal image's blur becomes larger with a decrease in the spatial frequency of the attention-getting component wave. These results suggest that accommodation for motion images is determined based on the interaction between the accommodation mechanism and the motion detecting mechanism.
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  • Sumio Yano
    Type: Article
    Pages 89-94
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We examined the relationship between information as it is perceived by the human visual and vestibular systems. In this experiment, we used images from horizontally rotated camera for the visual information, and displayed these images through a head mounted display. Also, we set up an angular acceleration using a turntable as information to be perceived by the vestibular system. The direction of rotated cameras and the turn table were separately controlled, and the direction were varied. From the results of this experiment, we found that the human visual system hold a dominant position in the case of low stumili for the vestibular system, and the human visual and vestibular system fulfill excessively in the case of perceptible stimuli for the vestibular system.
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  • Yoshihiko Seri, Takashi Okuma, Kiyoshi Kiyokawa, Haruo Takemura, Naoka ...
    Type: Article
    Pages 95-100
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper describes a case study of implementating 3D user interface tool-kit. The tool-kit is designed for prototyping and constructing 3D user interface. The tookit provides 3D widgets and methods for direct manipulation of 3D primitives, and supports a variety of input and output devices for virtual reality systems. We describe the design policy and strategy of the tool-kit and introduce the implemented toolkit.
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  • Nobuhiro Aihara, Hidehiko Iwasa, Naokazu Yokoya, Haruo Takemura
    Type: Article
    Pages 101-108
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper proposes a new self-localization method using an omnidirectional image sensor which can observe a surrounding environment with 360-degrees of view. The method extracts information which is identical for the position of a sensor and invariant against the rotation of the sensor by generating an autocorrelation image from an observed omnidirectional image. The location of the sensor is identified by evaluating the similarity among the autocorrelation images in low dimensional eigenspaces. We have conducted experiments with real image sequences and examined the performance of the proposed method. The results show that accurate and robust estimation of the sensor's position is possible.
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  • Masanari Kanagawa, Kiyoshi Kiyokawa, Haruo Takemura, Naokazu Yokoya
    Type: Article
    Pages 109-116
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In a virtual reality system with a glove-based input device, the time lag affects on usability of direct manipulation of virtual objects. To find out how to improve the usability, we conducted two empirical studies. The experimental results show that visual feedback impedes direct manipulation with a large time lag. Also shown is that visibility of a real hand is effective in improving both manipulation efficiency and manipulation feeling.
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  • Type: Appendix
    Pages App1-
    Published: February 03, 1998
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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