Interactive functions in broadcast video-on-demand

Abstract

Broadcast schemes for Video-on-Demand (VoD) service are done according to a predetermined schedule. New clients have to wait for the beginning of the next instance of the target video stream. A video server may not be able to deviate from its scheduled video data retrievals when a video stream is shared by more than one client. With this difficulty, the possibility of providing interactive VCR (video cassette recorder) functions in broadcast VoD has not been well addressed. In this project, two broadcasting schemes are proposed and analyzed to address the issue of VCR functions in broadcast VoD service. Each scheme has its own merits in supporting interactive functions. The first scheme, called Skip-Forward Broadcasting (SFB), allows clients to reposition their points-of-play in a forward direction. The second scheme, called Short-Range Fast-Forward Broadcasting (SRFFB), is designed to support clients to view the video at a doubled speed in the forward direction. Further, both schemes support pause/resume interaction and 'on the fly' seamless channel transition without any user-observable disruptions. However these two schemes have a large requirement on the client-side buffers. To reduce the buffer requirement, two additional schemes are also introduced. The third scheme, called Mirrored-Pyramid Broadcasting (MPB), supports fast-forward with a reduced client-side I/0 bandwidth requirement. The fourth scheme, called Small-Buffer Skip-Forward Broadcasting (SB-SFB), is a modified version of the Skip-Forward Broadcasting scheme that reduces the buffer requirement by half