In the future Broadband ISDN. Asynchronous Transfer Mode (ATM) is to be the major transfer mode and widely employed for its user-network interface simplicity. Moreover, it allows terminals to vary their transmission speed and well suits to video signal transmission. Variable Bit-Rate (VBR) coding for video signals is one of the attractive technologies for B-ISDN, and has been widely studied. In this paper, some aspects of VBR video coding are described. The progress of standardization works for VBR video coding is also introduced.
