Abstract: A method and apparatus for compressing and restructuring video signals are provided to promote the usefulness of a video channel, resulting in the efficacy of accommodating more video programs in a single video channel. Several video compressing and restructuring devices are used to directly compress multiple digital video data streams which are then integrated by a multiplexer. Each of the video compressing and restructuring devices comprises a plurality of video compressors for compressing the video codes of the digital video data stream, and a multiplexer for integrating the video codes having been compressed by the video compressor. Each video compressor comprises a trancoder for properly adjusting quantization scale for further compressing video signals. Based on the present invention, video signals are directly compressed with simple method and apparatus of low cost, leading to the realizing of an analogy Video-On-Demand system (approximate to a Video-On-Demand system).

Abstract: The present invention optimizes data placement in reference to the service of cyclic re-broadcast, typical of a media server. When the media data to be re-broadcast and the cycle of the re-broadcast are known, it is possible, according to the present invention, to calculate the portions of all the media data that will be read simultaneously and place sequentially such portions of data, so that the search time of the read/write head in the data blocks of direct access devices, such as magnetic disks, magnetic disk arrays, read-and-write optical disks, and other storage devices, can be reduced. Using the inventive data placement technology, the search time of the read/write head can be significantly reduced and the efficiency of bandwidth use can be improved, without altering typical hardware devices.

Abstract: The present invention discloses a network access admission controller and the method used to determine its schedulability. The basic principle involves determining, for all the connections to be checked, if there is any time slot, among all the time slots within a cycle, that will satisfy the scheduling property without the possible misjudgment of schedulability found in the conventional technology. The inventive method of determining schedulability makes its judgment based on packets issued by all the connections and on each of these connections individually. In particular, a determination is made regarding whether there is a particular time slot, among all the time slots, corresponding to the cycle of connection under evaluation, such that all the time slots prior to it are capable of processing the previously issued packets from the connections having higher priority than this particular time slot.

Abstract: An improved method is disclosed for placing continuous media data in a memory storage disk that will increase the disk operating efficiency and increase the number of users in a service round.