番組多重テレビ方式の放送教育への応用 : シミュレーションによる検討と放送大学への提言

概要

論文の詳細を見る
For educational broadcasting purposes, it is desirable that as many programs as possible be transmitted. The research investigated whether the still picture TV system developed by NHK could provide such a service. Experiments were conducted using simulation video recordings taken from conventional programs broadcast by the University of the Air, Japan. There are two ways of selecting the still picture frames. One way is by fixed limited time intervals. In the case of a picture showing an average level of movement, too short a time is irritating to the viewer. In the case of a picture depicting little movement, a long interval, even one of 10 seconds, is preferable. An acceptable duration for all pictures is of 2 to 4 seconds. Another way which gives viewers the more notural feeling, is by picking out pictures at not periodic but desirable instances. The problem is that pictures from different programs may coincide on the same frame. When 48 programs are transmitted simultaneously, overlapping is likely to be 20% of any one program. It is considered that the reasonable number of simultaneous broadcasts, in this second way, be in the region of between 10 and 20. Our results indicate the potential that exists to expand the number of programs broadcast, in the future. This is a concept which may be of use in the development also of the "multimedia system".
放送大学の論文