Abstract: A method receives first and second copies of a video stream by first and second video processing devices, respectively, and processes the first and the second copies of the video stream to generate first and second statistical data for the video stream, respectively. The method transmits in first and second transmissions the first and the second copies of the video stream with the first and the second statistical data respectively from the first and the second video processing device to a third video processing device, and reads the first and the second statistical data from the first and the second transmissions by the third video processing device. The method then combines the first and the second statistical data with one copy of the video stream by the third video processing device, and transmits the one copy of the video stream with the first and the second statistical data.

Abstract: A method for processing a video stream includes receiving first and second copies of the video stream by first and second video processing devices, respectively, and generating first and second statistical data for the video stream by the first and the second video processing devices, respectively. The method further includes transmitting in first and second transmissions the first and the second copies of the video stream with the first and the second statistical data respectively from the first and the second video processing device to a third video processing device, and reading the first and the second statistical data from the first and the second transmissions by the third video processing device. The method further includes combining the first and the second statistical data with one copy of the video stream by the third video processing device, and transmitting the one copy of the video stream with the first and the second statistical data.

Abstract: A method for processing a video stream includes receiving first and second copies of the video stream by first and second video processing devices, respectively, and generating first and second statistical data for the video stream by the first and the second video processing devices, respectively. The method further includes transmitting in first and second transmissions the first and the second copies of the video stream with the first and the second statistical data respectively from the first and the second video processing device to a third video processing device, and reading the first and the second statistical data from the first and the second transmissions by the third video processing device. The method further includes combining the first and the second statistical data with one copy of the video stream by the third video processing device, and transmitting the one copy of the video stream with the first and the second statistical data.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composited video stream, encoding the composited video stream to create an encoded composited video stream, and restoring the encoded composited video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composited video stream, encoding the composited video stream to create an encoded composited video stream, and restoring the encoded composited video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composited video stream, encoding the composited video stream to create an encoded composited video stream, and restoring the encoded composited video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: Multiple-frame format data streams are selectively encrypted at a master head-end prior to distribution. Selective encryption includes monitoring packet for frame header information. Only packets that do not contain frame header information are encrypted, while those that contain frame header information are left unencrypted. Splicers at distribution hubs can then interject local content into the data streams and forward these to individual subscribers at the local node groups.

Abstract: An auto-adaptive program distribution system in which content is transmitted from one or more content providers to one or more subscribers each associated with a service group includes an auto-adaptive switch whose inputs is a set of programs from the content providers and whose outputs are grouped into at least two groups, the first of which is dedicated to broadcast programming directed to multiple service groups, and the second of which is dedicated to switched programming sent to one or more of the service groups. The switched programming group includes at least one program selected on an on-demand basis. The auto-adaptive switch is provided with an analysis module which handles the group allocation, and makes its assignments based on statistical analyses performed in accordance with prescribed algorithms which take factors such as seasonal television viewership, seasonal and aberrational events and programming, time of day, week, year, and so forth.

Abstract: A data processing apparatus for a first encrypted digital datum in a digital data stream distributed in a distributed system. The apparatus includes a key extractor for obtaining a symmetric encryption key used to encrypt the first encrypted digital datum; a decryption system for creating a plaintext digital datum from the first encrypted digital datum using the symmetric encryption key; a processing system for operating on the plaintext digital datum to produce a modified plaintext digital datum; an encryption system for creating second encrypted digital datum from the modified plaintext digital datum using the symmetric encryption key; and a transmitter for introducing the second encrypted digital datum into digital data stream.

Abstract: A system for conducting fast-channel switching of programming delivered as compressed data streams over a unicast channel includes a switch for receiving both fully-compressed and a partially-compressed versions of the data streams corresponding to available programming. Upon receiving a channel change request from a user, the switch switches to a partially compressed data stream of the requested program and delivers this data stream over the unicast channel. The switch then monitors a fully-compressed data stream of the requested program, and upon encountering an anchor frame therein, switches to delivery of the fully-compressed version of the requested program over the unicast channel.

Abstract: Motion graphics keying in the compressed domain may be accomplished by receiving a compressed video stream comprising one or more source macroblocks, receiving a keyed graphics stream, determining which of the one or more source macroblocks overlaps with the keyed graphics stream, decoding only the one or more overlapping macroblocks to create one or more decoded macroblocks, combining the keyed graphics stream with the one or more decoded macroblocks to create a composite video stream, encoding the composite video stream to create an encoded composite video stream, and restoring the encoded composite video stream in the compressed video stream in place of the one or more overlapping macroblocks.

Abstract: A method and apparatus for optimizing the data transfer rate over a transport layer (i.e., communication link) such as the Internet is provided. Initially the data is prepared for transmission by a transfer rate controller, then the data is encoded by a Forward Error Correction (FEC) encoder. After the data has been transferred over the transport layer, the quality of the data transfer link is assessed by an FEC decoder that determines if any errors occurred during data transfer and if errors are detected, the magnitude of the errors (i.e., FEC-correctable packets, FEC-uncorrectable packets). This information is used to generate a feedback message which is used by the transfer rate controller to adjust and optimize the data transfer rate for the link quality as determined at that point in time. By continually monitoring and assessing link quality and providing feedback to the transfer rate controller, the transfer rate can be continually adapted to the varying link quality.

Abstract: In a video system having an encoder and multiple decoders, a snooping circuit in each decoder compares an address on a common data bus to determine whether encoded video data is read or written by a host computer. When the address on the common data bus is detected to be an address within a predetermined range, the read or write data on the common data bus is latched into a first-in-first-out (FIFO) memory. A decoding circuit in each decoder decodes from the FIFO memory to provide a decoded video data output stream. In this manner, multiple decoders can be supported by the video system without additional bandwidth demand on the host computer.