System requirements and considerations for visual table of contents in personal video recording

With the introduction of non-tape based digital video recorders, consumers can expect alternative navigation methods to the well-known trick-play modes found on analog and digital tape-based systems. In this paper, we explore the system requirements and aspects of the Visual Table of Content (VTOC). One reason for implementing a VTOC search mode is that it provides a much higher visual performance at high search speeds (50 times or higher) than the conventional search techniques. We present a solution based on re-using MPEG-compressed video data to generate the video signal for the visual search. The video search signal is composed of a set of sub-pictures (mosaic screen) each of which is MPEG compressed An efficient strategy is introduced that allows either full or partial re-use of the compressed sub-pictures to allow the generation of a new mosaic screen.