Abstract: A multi-threaded digital versatile disc system which is controlled by a system thread includes an independent counter thread for controlling the counter parameters. Only the counter thread (and not the system thread) increments and decrements the counter parameters based on an input from the system clock. Counter parameters can be attached, or associated, with the counter thread and all associated counter parameters are incremented together by the thread. The counter thread has a semaphore and a queue associated with it and the counter thread remains dormant until woken up by the semaphore. The semaphore queue receives periodic messages from the system clock via a conventional operating system mechanism and periodically increments and decrements its associated counter parameters. Other threads, originating from this system or from another system, can also communicate with the counter thread by means of the queue by directing an event message to the operating system which places the message in the queue.

Abstract: A method and system of read-ahead caching for use in a DVD player utilizing CSS titles is disclosed. The caching system is a host-based read-ahead caching system that utilizes a threaded architecture for caching. One thread is dedicated to retrieving data from the cache and a second thread is dedicated to reading data from the cache. The producer thread is intelligent enough to cache only within a title boundary, thus preventing costly re-authentication steps.

Abstract: A multi-threaded digital versatile disc system which is controlled by a system thread includes an independent counter thread for controlling the counter parameters. Only the counter thread (and not the system thread) increments and decrements the counter parameters based on an input from the system clock. Counter parameters can be attached, or associated, with the counter thread and all associated counter parameters are incremented together by the thread. The counter thread has a semaphore and a queue associated with it and the counter thread remains dormant until woken up by the semaphore. The semaphore queue receives periodic messages from the system clock via a conventional operating system mechanism and periodically increments and decrements its associated counter parameters. Other threads originating from this system or from another system, can also communicate with the counter thread by means of the queue by directing an event message to the operating system which places the message in the queue.

Abstract: A method and system are disclosed for allowing selection of an icon most logically desired by the user in a graphic user interface when multiple icons are overlapping and the pointing device coordinates would force a given selection not desired by the user. A logical icon selector is provided that is coupled to the pointing device and provides a logic for selecting the desired icon based on proximity of the pointing device icon to the desired icon. Based on a calculation of the location of the overlapping icons to the pointing device icon, the icon having the closest proximity to the pointing device is selected.

Abstract: 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.

Abstract: A DVD playback system in accordance with the principles of the present invention provides a method and apparatus in which a pointing device, such as a mouse, a joystick, or a stylus may activate "non-user" buttons while conforming to the DVD specification. The DVD playback system responds to the tentative selection of a non-user button, i.e., a target button by determining whether the target button would be a connectable destination, if any directional button were activated while the current button is selected. If the target button is accessible to the currently selected button via directional commands, the playback system determines whether there is a connectivity path between the currently selected button and the target button through one or more intermediate buttons. If such a path exists, the playback system selects each intermediate button until the target button is reached, at which point the target button is selected.

Abstract: A media player includes an input manager and an input driver. The input manager operates between a device driver and a player application program. The input manager provides a uniform interface for input drivers and, upon receiving a command from an input driver passes the command along to an application program. The input manager ranks input devices according to a user's preferences and, should the input manager receive commands from more than one device driver at one time, the input manager passes along the commands in accordance with the user's input device preferences. Each input device driver provides the input manager with an indication of the driver's capabilities so that the input manager passes the appropriate information, such as location information in the case of a location sensitive input device's driver, to the driver. Each input device driver also performs the translation of input signals into a format that is acceptable by the input manager.

Abstract: The set up information associated with at least some of a DVD disc's titles are stored in a DVD player's local memory. Items are chosen for storage based upon the likelihood that a title will be played. The likelihood that a title will be played is balanced against the availability of local memory for storing this information. Titles are ranked according to the likelihood they might be played and titles of lower rank may be purged from the local memory, or title cache, set aside for this task. Six basic criteria are used to rank a title as extremely likely, highly likely, likely, or not likely to be played. A title ranked extremely likely to be played has top caching priority, one that is highly likely to be played has the second highest caching priority, and so on. Each time a title's set up information is read, the title is ranked for caching. Additionally, the state of the title cache is stored every time a user plays a DVD.

Abstract: A digital signal manager that dynamically chooses between hardware and software compression/decompression (CODEC) so as to maximize the usage of any digital signal device hardware capabilities; and that provides a common, uncompressed data interchange format for applications regardless of any compression technique that may have been used to create the data file.

Abstract: A specialized linked-list editing structure is used to order multimedia file segments in a multimedia file to be edited. Each multimedia file segment is comprised of a number of contiguous data units, which may preferably be bytes, that are portions of the overall multimedia file even though the file segments may be physically located in different data files. The linked list is arranged as a plurality of nodes where each node represents a single file segment and the linked list orders all of the file segments to make up the entire multimedia file. Accordingly, editing can be performed at the data unit level so that both compressed and uncompressed files can be handled. Editing operations on the file result in changes to this linked-list structure instead of the file itself, thus avoiding the necessity of making file copies. More particularly, the linked-list structure consists of a list of records called "file descriptor nodes".