Recentry, high quality moving pictures are needed in various fields. Here, we propose a new scheme to improve moving picture quality. It uses picture structure and the spatio-temporal continuity of the moving pictures. Unnecessary regions are deleted by using segmentation and hierarchical representation of region. The deleted regions are reproduced by interpolation using motion compensation based on linear vector field approximation and spatio-temporal integration. The proposed scheme is applied to moving pictures degraded by white additive Gaussian noise and its effectiveness is verified.

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In this paper, we propose a new method of color image quantization. This technology is for a color map display. which has a limited capability due to the size of a frame buffer. Firstly, a color image is segmented into some small blocks, and the number of colors to be as-signed to each block is determined according to t,he sharpness of the corresponding block. Sharper the block is, more colors are assigned to the block. A set of DCT coefficients of the block is used as a parameter of the sharpness. This met, hod enables to assign more colors to the characteristic area even if the area is small. Several experimental results show that the subjective quality. of the displayed image is improved especially for natural images.

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Communication sevices over communication satellites, especially video distribution sevices, have being remarkably widespread according to the increase of satellites. In satellite video communication systems, digital coding and transmission is expected to realize efficient use of the channel by multiplexing video channels into one transponder, and to improve the interference characteristics. In this papar, a compact digital TV decoder is introduced which was developed using a VLSI chip comforming to the MPEG-1 international standard video coding algorithm. The decoder was evaluated over a real sattellite channel and was confirmed to operate normally and to provide a cost-effective "Satellite multimedia broadcasting system".

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In order to transmit a high resolution still Picture over ISDN network, we have developed the still Picture transmission equipment. It utilize the JPEG Still Picture coding scheme and can be connect to a Personal Computer and a SVP( Still Video player) by RS-232C and SCSI interface. By converting a picture control circuit to LSI and employing high density mounting technology, we can realize to make the equipment light weight and miniaturization. We also developed compact size protocol which enable to transmit a picture from this equipment to another by end-to-end type packet.

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