This paper proposes a bitstream scaling technique for MPEG video for the purpose of media synchronizations. The proposed scaling technique can reduce the frame rate as well as the bit rate of an MPEG data sequence to fit them to the values specified by a synchronization system. The advantage of the proposed technique over existing scaling methods is that it is considering not only the performance of synchronization but also the picture quality of the resulting sequences. To further improve the quality of sequences scaled by the proposed method, this paper also proposes an MPEG encoding technique which sets some of the parameters suitable for the scaling. An experiment using these techniques in an actual media synchronization system has illustrated the usefulness of the proposed approach.

A plastics such as polycarbonate take a graded birefringent orientation when a high dc ununiform electric field is applied to its molten phase. This ununiformity is maintained even in a solid phase after decreasing the temperature. Therefore, the plastic plate operating as a variable retardation plate is easily and inexpensively fabricated by using this bulk plastics with graded birefringence.

The fiber type dye laser composed by modulating a commercial grade plastic fiber has been studied. One is the active clad type and the other is the coupling waveguide type. These active fiber pumped by a pulsed N2 laser generate the intense emission of the superradiant mode with the spectrum width of 35 nm.