Abstract: A method and a system for performing trick mode features in a personal video recorder without introducing a channel change delay during normal viewing. The method includes the steps of recording a video source signal and concurrently bypassing the video source signal to a display device, without experiencing any buffering delay associated with the recording step. During trick mode operation the bypassing step can be automatically terminated and a recorded version of the video source signal can be substituted and sent to the display. The bypassing step further can include substituting, without any buffering delay, an alternate video source signal in response to a user selection of an alternate video source signal channel. A user notification can be generated to acknowledge receipt of a trick mode command. The user notification can be terminated once the step of substituting the recorded version of the video source signal has been completed.

Abstract: A method and apparatus for simultaneously recording and displaying video signals from two different video sources. The apparatus comprises a main channel processing circuit/logic (148), a second channel processing circuit/logic (150), and common circuitry/logic (152). The common circuitry comprises a digital video encoder pipe (112) that decodes both a first and second encoded video signals. The main channel processing circuit processes a first decoded video signal utilizing a first clock to form a main picture for display. The second channel processing circuit processes a second decoded video signal to form a PIP picture for combination with the main picture for display. The PIP picture is produced using a second clock signal that is independent from the first clock signal. In a record mode, the second channel clock is coupled to the second channel processing circuit to produce a recordable signal using a digital encoder.

Abstract: A Conversion system merges and converts data in a plurality of different data formats from a plurality of different sources, to a selected output data format for transmission on a selected transmission channel. A method for digital data format conversion involves de-packetizing an input packetized datastream. A timing recovery parameter is formed in response to a desired output data format. The depacketized data is re-packetized in response to the desired output data format and the timing recovery parameter is incorporated in the re-packetized data. The re-packetized data is multiplexed in response to the selected format and provided to an output channel.

Abstract: A decoder conditional access system incorporates different encryption systems for providing access to programs derived from different sources. A conditional access processor for processing encrypted program data and an associated encryption code includes a first algorithm means for decrypting the encryption code to provide an encryption key. The conditional access processor also includes a second algorithm means for encrypting the encryption key and the second encryption algorithm is different to the first encryption algorithm. A datastream representing the program is generated from encrypted program data and an associated encryption code. The encryption code is decrypted to provide an encryption key using a first algorithm. The encryption key is encrypted using a second algorithm different to the first encryption algorithm and the program datastream is formed from the encrypted program data and the encrypted encryption key.

Abstract: An adaptive decoder generates a program representative datastream, in selectable, encrypted or decrypted form. A method for adaptively processing input encrypted program data with an associated encryption code provides either an encrypted or a decrypted program output. In an encrypted mode, encrypted program data and an associated encryption code is exported to an output port. In a decrypted mode, input encrypted program data is decrypted using an encryption key derived from the encryption code to provide decrypted program data. The decrypted program data is exported to the output port. Non-encrypted program data is exported to an output port in a selectable non-encrypted mode.

Abstract: A decoder excludes an encryption code or key from decrypted or non-decrypted program output data. Decrypted program representative data is generated from an input datastream containing encrypted program data and an associated encryption code. The encrypted program data is decrypted using the encryption to provide decrypted program data. An output datastream is formed containing the decrypted program data but excluding the encryption code. The encryption code may be excluded by submitting non-encryption code data for the encryption code. The output datastream may also contain ancillary date formed to support decoding of the decrypted program data.

Abstract: Program specific information (PSI) is formed suitable for use in recovering data content of a program in the form of a packetized datastream. Packet identifiers (PIDs) that identify individual packetized datastreams constituting the program are renumbered and corresponding packetized datastreams that constitute different programs are given the same PID. A program map table (PMT) is created that associates the renumbered PIDs with the individual packetized datastreams constituting the program. A program association table (PAT) is also created for associating the program with PIDs that identify packets comprising the PMT. A parameter may be employed within the PSI to indicate that the PSI is to be applied in subsequent processing of the program irrespective of a substantive difference between the PSI and previous PSI content. In addition, the PSI may incorporate a version number that is varied between successive occurrences of the PSI irrespective of substantive change in PSI content.

Abstract: A decoding method minimizes the use of incorrect program specific information (PSI) parameters across program boundaries and provides default video and audio outputs for reproduction during error conditions. Program representative packetized datastreams incorporating PSI suitable for use in recovering data content of the program are decoded. PSI packets in the datastream are identified and a parameter within the identified PSI data is used to determine whether the identified PSI data is to be used for decoding the program content, irrespective of previous PSI content. Current PSI is updated with the identified PSI data in response to the parameter. Program content packets are identified using the current PSI. The program content packets are assembled into a decoded datastream using the current PSI. The current PSI may also updated with the identified PSI data irrespective of the content of the identified PSI data, provided that there is an absence of a PSI content error indication.

Abstract: A storage medium format for a storage medium containing packetized data programs includes packet identifiers (PIDs) that identify individual packetized datastreams constituting a program. The data format facilitates the association and assembly of the packetized datastreams of the program by a decoder, independent of PID de-mapping data. The PIDs include a base PID for identifying one datastream and a second PID of predetermined offset value to the base PID for identifying a second datastream. Corresponding packetized datastreams that constitute different programs are given the same PID. The storage medium format may also include program specific information (PSI) suitable for use in recovering data content of a program. The PSI includes an MPEG-like program map table (PMT) and an MPEG-like program association table (PAT) and incorporates a parameter suitable for commanding a decoder to apply the PSI in decoding the program irrespective of previous PSI content.

Abstract: A program representative packetized datastream is generated from an input packetized datastream representing a plurality of programs. Program content packets comprising a desired program selected from the plurality of programs are identified. Condensed program specific information (CPSI) suitable for use in identifying and assembling the identified packets is formed. The resulting CPSI and the identified packets are formed into a datastream. Program specific information packets and program content packets are also extracted from a packetized datastream and stored on a storage medium.