| 摘要 |
PURPOSE:To select a receiving picture signal required for a subscriber, by storing previously the receiving picture signal within a fixed time together with transmission source information in a store and forward exchange and by causing the subscriber to index transmission source information. CONSTITUTION:The subscriber which wants to obtain the right of choice of the picture signal records transmission source information for the picture signal, which is transmitted within the time designated by the subscriber, and the picture signal into store and forward exchange part STOC. After a while, when the indexing request of the receiving picture signal for example, comes to toll siwtch TS from, Sub B, TS reports it to STOC, and STOC transmits transmission source information to Sub B. Sub B determines a required picture signal on a basis of transmission source information and transmits its number to TS with the PB signal. When receiving PB, TS reports it to STOC. STOC reads out the requested picture signal on a basis of the number of the requested picture signal and transmits it to Sub B. |
