This paper proposes a method to detect the positions of point symmetrical industrial components by using the normalized correlation matching. The objective image is divided into plural square blocks with the same size and all the blocks set as the original template image. The inverted template images are generated by inverting all the original template images. In this method, the template matching is executed using all the inverted template images, and the position of symmetrical components is extracted by the result of the voting process to the candidates for the centers of point symmetry. The experimental results show that the proposed method detected the point symmetrical components successfully.

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A data hiding method for ordered dither images with keeping enough picture quality was proposed and studied for typical threshold ordering methods. The proposed method only embeds the data to flat patterns, which dominate the possible block patterns, and makes the image after embedding to be also flat patterns. This method has also the effect to prevent the data embedding on text area, which usually causes strong damage to the image quality. It is acknowledged that the embedded image by proposed method is better than one by conventional method in picture quality and in data compression ratio. By controlling the data embedding frequency, we succeeded to introduce the unnoticeable embedding rate for various images.

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This paper describes problems of the FAX transmission via modem as a part of VoIP service, and proposes the solutions of the problems on the theoretical and experimental bases. The characteristics of the VoIP network, compared with the PSTN (Public Switched Telephone Network), are analyzed and the requirements for FAX communication are studied. Three problems emerge as results of the analysis and the study: echo problem, wave shape reproduction problem, and dial timer problem. The three problems are confirmed by experiment, and the solutions are proposed, based on the analysis and the experiment.

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We have developed a LC rear-projection display with a novel aspherical mirror projection optical system. This system realizes the LC rear-projection display with thiner depth compared with a conventional projection lens system. The aspherical mirror is a key-part of this display and can be manufactured by the method of resin mold whose shape and accuracy is simulated and analyzed. Also a most suitable screen was developed for this rear-projection display for suppression of image ghost on the screen. By using these technologies we carried out development of a thinner LC rear-projection display with high quality images.

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A data embedding method, which is based on the two-dimensional phase modulation of sampling lattice, has been proposed. In this paper, we present an improved version of the phase modulation based data embedding method, which has no use of original images in the decoding process.

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