[in Japanese]

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[in Japanese]

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[in Japanese]

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Transform coding is frequently used in the high-efficient coding of images. In transform coding, a bit allocation map is determined according to the statistic of images. Usually, the map is calculated to minimize the coding error for a given bit rate. However, this paper proposes an other scheme in which a bit allocation is determined to minimize the bit rate for a given coding error. In general, the usual method is suitable for producing devices when transmitting television images. However, the second method is effective in maintaining image quality, when transmitting many freeze frame images having different statistic and storing many images in the storage mass. An analytical formula was derived for the proposed method and good performance was obtained by computer simulation. A desired quality (SNR) of images can be easily obtained using this method.

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This paper proposes a recognition system for novels written in Japanese using a personal computer. This system consists of a document image processing unit and a character recognition unit. In the former, normalizaton of the document image and extraction of the character patterns are carried out. In the latter, pre-classification and recognition of character patterns are conducted. An the experiment involving 56, 054 characters on 93 pages in the novel achieved on average recognition rate of 98.15%. The average Processing time was 3.1 sec/charahter.

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A transmission system using one satellite broadcasting channel in the 12GHz band to broadcast many PCM high-quality sounds multiplexed by time division is presented. This multiplexed signal digitally modulation a carrier wave by using the orthogonal carrier modulation method. In this system, the frame format, Which has a 2.048Mb/s transmission bit-rate is a single channel sharing the transmission signal format of PCM sound for satellite TV broadcasting. This system can transmit 12-16 multiplexed channels by improving the effectiveness of error correction code and error control by range transmission. Transmission characteristics and sound-quality are assessed by a satellite transmission experiment. This system is found to be acceptable for sufficient sound quality broadcasting service, even if the received C/N is degraded.

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[in Japanese]

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[in Japanese]

View full abstract