SYSTEM AND METHOD FOR VIDEO STREAM ENCRYPTION |
USA
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Abstract
A system and method of video stream encryption. A storage device stores a first quantization scale and a second quantization scale. An encryption application receives video data, a first quantization scale and a second quantization scale, generating quantized data by dividing the video into the first quantization scale, generating supplementary data by subtracting the quantized data multiplied by the first quantization scale from the video data, generating quantized supplementary data by dividing the supplementary data into the second quantization scale, and generating encrypted quantized supplementary data using variablelength encoding and symmetrical/asymmetrical encryption algorithm.
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TRANSCODER SYSTEM FOR ADAPTIVELY REDUCING FRAME-RATE |
USA
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Abstract
A transcoder system for adaptively reducing frame rate is provided, which can change audio-visual stream of a GOP (group of picture). Each picture in the GOP consists of a plurality of macroblocks. The transcoder system includes a switching device, a variable length decoder, a motion vector compensation device, a memory and an encoder/decoder. The motion vector compensation device can compute output motion vectors respectively for the macroblocks in accordance with input picture types, so video data of I-, P-and B-pictures without complete reduced frame-rate transcoding in the prior art can be avoided. Therefore, video transcoding for pictures can be performed completely and quickly to thus reduce required transcoding computation and further increase transcoding speed.
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INTERMEDIA SYNCHRONIZATION SYSTEM FOR COMMUNICATION MULTIMEDIA DATA IN A COMPUTER NETWORK |
USA
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Abstract
The inventive system mainly includes a synchronization marker at a transmitting site and a synchronization forcer at a receiving site connecting to each other via computer networks. The synchronization marker performs the sequential mark marking of frames per every marking interval. The synchronization forcer regulates the play time of the audio signals and their corresponding video signals according to their sequential marks. The inventive system can determine precisely about the minimum marking interval yielding a bounded skew requirement. Consequently, the invention satisfies any given skew requirement under various buffer size and traffic arrivals while imposing minimal overhead.
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PERIPHERY DEVICE IN A WIRELESS NETWORK |
USA
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Abstract
Apparatus for transmitting a signal from a periphery device to an Internet through a wireless local area network is disclosed herein, the apparatus including the following devices. Firstly, the converting device is used to transmit the signal between the local area network and the Internet using pack exchanging. Thus the frame is briefer than that used in the prior art. The frame is transmitted between the periphery device and the local area network with the frame of a brief structure. Second, the converting device is used as the bridge between the wireless local area network and the local area network. Third, the transceiving device is used to transmit the signal to the converting device through the wireless local area network. The transmitting periphery device is used to transmit a first output frame to the transceiving device. Thus the first output frame is sent to the converting device through the wireless local area network. Fourth, the receiving periphery device is used to receive the signal from the converting device.
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STACKABLE UTOPIA SWITCHING APPARATUS FOR A BROADBAND SWITCHING SYSTEM |
USA
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Abstract
A stackable UTOPIA switching device for use in an Asynchronous Transfer Mode switch is provided to connect to more digital subscriber lines (DSL). The inventive UTOPIA switching device can work along or be arranged in a tree-like hierarchy to connect to more DSLs. The UTOPIA switching device comprises an Up-link end and a down-link end. The down-link end can connect to 31 slave multiplexers or physical layers at the most. The up-link end can connect to master USD or slave USD. Both the up-link end and the down-link end have three input queues and an output queue for storing the cells. The cells are stored in the input queues and the output queues according to the control of a priority queuing logic circuits.
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SYSTEM AND METHOD FOR ON-DEMAND ACCESS CONCENTRATOR FOR VIRTUAL PRIVATE NETWORKS |
USA
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Abstract
Two stages of PPP negotiations are adopted for users to access a virtual private network (VPN). The access concentrator for providing PPP connections is designed to provide the two-stage connection. In the first stage, a user is verified as an authenticated VPN user, and a first network address is assigned. In the second stage, a service requested by the authenticated user is decoded for determining either the service being a VPN service or a non-VPN service. If the service is a non-VPN service, the request is processed by reference to the network address. Otherwise, a second PPP negotiation is executed between the access concentrator and a server in a VPN, and then the server of the VPN assigns the user a VPN address for providing VPN service.
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MULTI-LINGUISTIC WIRELESS SPREAD SPECTRUM NARRATION SERVICE SYSTEM |
USA
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Abstract
A multi-linguistic wireless spread spectrum narration service system includes a speech database, a plurality of basestation units, and at least one mobile unit. The speech database is stored with multi-linguistic narration service speech messages. The plurality of basestation units are arranged at each exhibition section of an exhibition field. Each basestation unit controller captures narration service speech messages from the speech database and a wireless communication is performed. The mobile unit controller is provided to be worn by a visitor. The mobile unit detects the wireless signals of a specific basestation unit. Thus, a synchronous or asynchronous connection is built through the spread spectrum radio frequency processing and baseband processing module. Therefore, the narration service speech message from the basestation unit is received.
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Double-threshold admission control method in cluster-based micro/picocellular wireless networks |
USA
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Abstract
There is disclosed a double-threshold admission control method in cluster-based micro/picocellular wireless networks. The method provides a cluster level threshold and cell level threshold. When the number of occupied channels in the cluster is less than the cluster level threshold and the number of occupied channels in the cell is less than the cell level threshold the mobile user is admitted to enter a cell. Otherwise, the mobile user is refused to enter the cell.
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METHOD FOR FINDING AND RESERVING AVAILABLE BANDWIDTH IN MULTIHOP MOBILE WIRELESS NETWORKS |
USA
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Abstract
A method for finding and reserving bandwidth in multihop mobile wireless networks is disclosed, which first finds the common free slots of all the links on a path, and marks the common free slots as “available” slots. Then, the slots among the common free slots which are not on the same positions in the TDMA frame as the common free slots of the downstream and upstream links for each link are found and marked as “reservable” slots. The current bandwidth of a link is defined as the current number of reservable slots on the link. Next, An iterative process is performed to try to increase the bandwidth of the link having the smallest current bandwidth such that the bandwidth of the path can be increased.
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FLEXIBLE AND HIGH-SPEED NETWORK PACKET CLASSIFYING METHOD |
USA
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Abstract
A flexible and high-speed network packet classifying method is disclosed. A plurality of aggregated flows (Aflows) are defined, each corresponding to an Aflow ID and described by symbols in fields of headers of a plurality of network packets. The tokens of the fields of the headers of the plurality of network packets are extracted. A bit stream pool of a memory is indexed responsive to the token of the field by using a two-stage index manager, wherein the bit stream pool has a plurality of bit streams, each having a plurality of bits arranged serially, and each bit corresponds to an aggregated flow. A bits-and operation is performed for a plurality of bit streams obtained from the bit stream pool for classifying network packets.
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