[in Japanese]

View full abstract

In the past, when TV viewers saw important information (such as a map) on TV and wanted to keep that information, they had to write it down. To simplify this, we developed a printing method that uses a data-casting service. This method was accepted by the Association of Radio Industries and Business in early 2004 and was published as STD-B24 Version 4.0. In this method, important information is sent via a data-casting service as a printable (XHTML-print) data file with BML. The service was developed on the basis of STD-B24 Version 4.0 specifications. Because the digital TV does not have a printer driver, printable data has to be sent in a deviceindependent format such as an XHTML-print file. After a TV receives broadcast data, the XHTML-print file is transferred from the TV to a printer, and the user can print high-quality images and data. We have now designed and developed optimized method of BML programming in order to make the best of STD-B24 Version 4.0, and have evaluated the performance and effectiveness of this method.

View full abstract

The 'Kabushiki Shikyo' program, broadcast on NHK Radio 2, reports on the daily closing prices and net changes of about 830 stocks listed on the Tokyo Stock Exchange. Reading out the numerical values within the allotted broadcast time without making mistakes can be extremely difficult for the announcers. We have therefore developed a prototype voice synthesizer for stock-price bulletins, which uses numerical speech synthesis and automatic speech-rate conversion. Our prototype system has been used in experimental digital terrestrial radio broadcasts since October 2006. This article describes the generation of texts to build the speech waveform database, the mechanism used to synthesize numerical speech via the database, the evaluation of naturalness of synthesized speech samples, and the prototype system currently being used by experimental digital terrestrial radio.

View full abstract

Mobile relay broadcasting requires better antenna reception techniques in order to expand the receiving area. We are developing a tracking and receiving system using a phased array antenna that can operate even in severe multipath fading conditions. Accurately estimating the direction of arrival (DOA) is key to making this system work effectively. We developed a method for estimating the DOA using pilot signals allocated to specific carriers over the bandwidth of the orthogonal frequency-division signal. We also analyzed the effects of multipath interference on estimation precision. We then fabricated a prototype system and demonstrated its capability for mobile relay broadcasting in an outdoor experiment.

View full abstract

We have developed a mobile robot camera that can move in any lateral direction, as well as up and down, as a tool for efficient program production. The system adopts methods that utilize a gyrosensor and the number of wheel revolutions to determine the camera's position, and that enable a high degree of positioning accuracy. It also uses a unique filming algorithm that simulates the operation methods used by human camera operators. Therefore, the robot camera can shoot scenes with natural camerawork. Moreover, we have developed a highly accurate image composition system using this mobile robot camera as a tool for the efficient production of HD virtual studio programs. The system is currently being operated on a continuous basis as a practical camera in live broadcasts as well.

View full abstract

The developments in mobile communication and broadcasting technologies have been remarkable. Developments in multi-functional planar antennas are especially desired for mobile communications. In this paper, single-feed planar antenna with three frequency bands printed on a dielectric substrate is proposed. Its resonance mechanism was clarified by analyzing the characteristics of return loss, radiation pattern, and current distribution on antenna elements using the FDTD (finite difference time domain) method. Moreover, two set-ups incorporating the three wireless systems were analyzed as an example of applications of the proposed antenna. One incorporated an 800 MHz cellular phone system, third generation cellular phone, and wireless LAN (IEEE802.11b). The return loss and radiation pattern characteristics were determined analytically and experimentally. The other incorporated digital terrestrial television broadcasting, a third generation cellular phone, and a wireless LAN (IEEE802.11b). Its characteristics were also determined analytically. These results showed that this antenna is useful as a multi-functional planar antenna in mobile communications.

View full abstract

A non-photorealistic rendering (NPR) method is presented for generating stippling on the basis of multiplicatively weighted centroidal Voronoi tessellations (CVT). Multiplicative weights are set and updated on the basis of the position of generating points and pixel values of an input image. This paper presents three kinds of multiplicative weights, that is, fixed, variable and monotonically nondecreasing ones. Experimental results show that the stipplings generated by the present method have sharper edges than that by multiplicatively unweighted CVTs.

View full abstract

This paper proposes a method for automatically generating a multimedia encyclopedia composed of video clips using closed-caption text information. The goal is to automatically index each video segment of the television program by the principal video object. We focus on several features of the closed-caption text style in order to identify the principal video objects. Using Quinlan's C4.5 decision-tree learning algorithm and the predicted accuracies of production rule indicators, we extract one object noun for each video shot. To show the effectiveness of the method, we conducted experiments on the extraction of video segments in which animals appear in twenty television programs on animals and nature. We obtained a precision rate of 74.6 percent and a recall rate of 51.4 percent on the extraction of video segments in which animals appear, and generated a multimedia encyclopedia comprising 322 video clips showing 82 kinds of animals.

View full abstract

A hand-held device that displays visual and force information has been developed. The display consists of an LCD panel and a moveable weight located at the back of the device. While the device is held, the force applied by the user's hands controls the weight's movement. The weight is moved by a PC-controlled servo-motor. Perceptual properties of a prototype display were investigated using force information and visual/force information. Force perception affected by the weight movement was psychophysically measured as a fundamental property. In an experiment, users sufficiently perceived force changes affected by the hands and caused by the weight's movement. Perceptual properties of the presented visual and force information were also discussed.

View full abstract

We compared the image quality of organic light-emitting diode (OLED) displays with that of LCDs by quantitatively measuring image quality parameters and subjectively evaluating images on the displays. Results showed that the black-level and contrast performance of OLED displays are superior to those of LCDs in a wide range of ambient light conditions. For these properties, the subjective image quality of fireworks images on OLED displays was particularly high. Image quality features of OLED display images are also discussed.

View full abstract

We report on an interface system in this paper for 10-ft and large screen environments. The proposed system uses penlights for operations, including pointing. Although the method pointing by the system is indirect, it is virtually direct. Several gesture-based operations have also been implemented, which are used for applications. We found that the system was easy to learn and that users could quickly master its operations through an evaluation experiment.

View full abstract