[in Japanese]

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This paper describes a method for restoring the defects inherent in video archives recorded in analog mode. The requirements for the restoration system are that it takes a short time and that it does not cost much. First, the nature and occurrence of the defects are examined for video archives. A restoration method is then proposed that is based on the characteristics of the defects. The method uses temporal and spatial median filters, the differences in luminance levels between the original and filtered images, and the chrominance levels of the original images. It restores not only the defects in small motion areas but also conspicuous white scratches without producing any artifacts. It has a semiautomatic mode, and it enables the selection of the temporal and spatial median filters and the number of frames for the temporal filter or the macroblock size for the spatial filter.

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We developed a new studio presentation system, that enables performers of the Virtual Studio to see imaginary objects within the studio, such as CG characters. In Virtual Studio productions, performers cannot directly see their CG interactive opponent. Therefore, performers must act while watching a composite image of themselves and the CG images, causing eye movements that are not synchronized with the CG images. This provides an unnatural impression to the viewer. To overcome this problem, we developed a system composed of an intermittently projected image that is shown only during the non-exposure time of the CCD camera, thus making it “invisible” to the camera. The projector can project imaginary objects, thereby enabling natural interactions between the performer and CG images. This system has been used in actual television programs, enabling performers with no previous experience with the Virtual Studio to perform naturally.

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This paper presents a new Internet radio news service using speech rate conversion technology. The key feature of this service is that three different speech rates (rapid, normal and slow) can be selected based on the user's needs. Using this service, for example, elderly users can listen slowly, and busy or visually impaired users can listen rapidly. This speech rate conversion service on the Internet will enable more wide spread use of information services to complement conventional broadcast services.

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We aim to develop an automatic contents production system of soccer video commentary based on digital shooting techniques, which consists of digital camera work and digital switching technique. Digital camera work is defined as virtual panning and virtual zooming. Virtual panning is a video production technique of clipping a fixed size frame and then controlling the frame location on a high definition material video. Virtual zooming is a video production technique of clipping a frame and then controlling frame size. Also, digital switching is defined as the change in virtual cameras by controlling the rapid change of frame location or size on a high definition material video. We describe a method of digital camera work that focused on players and a ball as a sub-system of an automatic contents production system for soccer video commentary. This study uses analytic hierarchy process to carry out subjective evaluation of the produced video contents with digital camera work.

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We have provided web casting services of the national high school baseball championship tournament since 1996. This paper describes our technical approaches to diverse multimedia content production in this service. Among the various techniques developed, we focused on implementing and operating data handling mechanisms to provide high-quality contents with low operational cost. They include video contents production for the Internet, management and utilization of the metadata, and web contents distribution. In addition, we also describe the knowledge and experiences obtained through the service's actual operation.

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This paper presents a fast and accurate line extraction algorithm. Conventional line extraction algorithms first extract the edge pixels and then connect these edge pixels into lines. In contrast the proposed algorithm extracts the lines directly from the input image by tracing the perimeter of an intensity region and then uses simple linear regression to compute the equations of the lines. This proposed method allows the algorithm to use the intensity information in the image to correlate the edge pixels, thus simplifying the computation of the lines and increasing the robustness in the presence of noise. Experiments were performed on a variety of synthetic and natural images and demonstrated that the algorithm can extract lines reliably, while realizing a large improvement in speed over the conventional algorithms.

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A display system that requires no special glasses is useful technology for 3D images. Conventional lenticular and parallax barrier display systems have the disadvantages of producing images with divided horizontal resolution and without see-through. We describe, a newly developed, 3D display with a parallax polarizer barrier that can avoid these problems. The advantage of the parallax polarizer barrier is that the resolution of the presented parallax images is much greater than conventional display. This is because the 3D screen can multiplex projected images with both horizontal and vertical polarizations to display stereo views. This 3D screen can be made more easily using a 1/2-wave plate and a polarizer. The trial screen is 10cm square and consists of two 1/2-wave plates using a liquid crystal (LC) cell and a polarizer.

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We describe a contour-based image representation using a wavelet transform and a contour-domain image editing system that we developed using the proposed representation. Contour-based image representations depict the properties of the image edges and are invertible between an image and its representation. The contour-based image representations based on the wavelet transform have been proposed for many image-processing tasks. However, the low-frequency component of the wavelet transform defines entire pixels for an image and is not associate with contour geometry. We introduced a sampling to the low-frequency component of the wavelet-based image representation and proposed a contour-based image representation that describes an image with only the edge-information associated with the contour geometry. We describe examples of the image recovery from the proposed representation and present an interactive image editing system based on the proposed representation.

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The impact of packet losses on broadcast-quality video transmission through an asynchronous network is discussed based on the quality of the video playback. The main requirements for broadcast-quality video transmission are quality, synchronization, and smooth failover. Therefore, video quality is also related to network quality in an asynchronous network. When video frames that contain network packet losses are decoded, noise-free video cannot be maintained for block noises caused in video playback. One of the most important features of real-time video data transmission through an asynchronous network is the ability to correct and conceal errors. Adding redundant bits to the source information, as in forward error correction and error correcting code, increases the data bandwidth. Adding redundancy, such as by interleaving, lengthens the latency of the video playback. The appropriate redundancy factor, therefore should ensure a real-time response, minimize latency, and maintain video playback quality. Therefore, when selecting an appropriate error correction/concealment code, it is necessary to clarify the impact of successive packet losses on the quality degradation of broadcast-quality video. To clarify the relationship between the broadcast-quality video quality and network packet losses, we analyzed data based on observation of an actual network with the loss window size as a parameter. Next, we discussed the characteristics of the block noises on the video playback using the Markov model. For this purpose, we made an 80, 000-km-long ATM path on the Japan Gigabit Network and examined the peak-signal to noise ratio of the SMPTE-314M.video playback that contained ATM cell losses.

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We previously developed and presented a theory and experimental results for the layered model of vision consisting of the external world, retina and brain. This model was shown to be very effective in evaluating image quality, and provides a means for comparative evaluations of various modulation methods. We have also proposed the equivalence approximation method, by which computation is made easier than the original model. The purpose of this paper is to propose the fixed equivalence approximation method. In this new method the window size is fixed, so there is no need to optimize the window size. This is a practical improvement, as the optimal window size are sometimes another size and may pose difficulty. We performed experiments using five kinds of modulation methods and three kinds of images. The results indicate that the proposed method gives an appropriate measure of objective evaluation that coincides with subjective evaluation, and can, therefore, be an alternative to the original model or equivalence approximation method. Moreover, the present method has an advantage of considerable time saving.

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Retraction of Duplicate Publication

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