System for dynamically optimizing DVD navigational commands by combining a first and a second navigational commands retrieved from a medium for playback

摘要

A DVD playback system having a navigation engine utilizes an optimizer which optimizes navigational commands to reduce the amount of memory required to store commands read from a DVD medium. The optimizer determines if a command is the type which may be combined with a subsequent command, and, if the following may be combined with the first. If so, the optimizer combines the two commands. Additionally, the optimizer re-orders command sequences before they are interpreted in order to permit their execution in parallel. After re-ordering the commands, the optimizer routes commands to either a primary or secondary execution unit for parallel execution. Commands are examined in the re- ordered sequence, with the first command encountered being routed to the primary execution unit and subsequent commands being routed to the primary or secondary execution unit depending upon whether they may be executed in parallel with commands in the primary execution unit without conflicting operations on the commands' operands.