Abstract: A system and method for displaying MPEG-2 packets as a hierarchy of tables within a window of a graphical display. This hierarchial display is updated continuously as new packets are received, thus providing a real time display. When a packet is received, and the location of that packet has not been identified, the packet is placed at the top of the hierarchy. Once a subsequent packet is received wherein the subsequent packet identifies the location of the earlier received packet, the earlier received packet is moved to its correct location within the hierarchy. When a user of the system clicks one of the tables within the hierarchy, the system saves the next data packet or packets containing data for the table into a display table buffer. The system then displays a second window and formats the data from the display table buffer into the second window.

Abstract: A method and a test instrument are provided for measuring program clock reference (PCR) jitter in a data stream, such as an MPEG-2 transport stream. The test instrument includes a line interface circuit for receiving the data stream, a digital computer for processing the data stream and a local clock for generating timestamps. The digital computer extracts from the data stream a PCR sample value which represents a count of a system time clock used to generate the data stream. The timestamp is obtained from the local clock and is associated with the PCR sample value. The digital computer determines a reconstructed system time clock from a set of values including the PCR sample value and the timestamp, and previously-received PCR sample values and associated timestamps within a window representative of a predetermined time interval. The window is shifted as new PCR sample values are received.

Abstract: A method and a test instrument are provided for measuring program clock reference (PCR) jitter in a data stream, such as an MPEG-2 transport stream. The test instrument includes a line interface circuit for receiving the data stream, a digital computer for processing the data stream, a local clock for generating timestamps and a display unit. The digital computer extracts from the data stream a PCR sample which represents a count of a system time clock used to generate the data stream. The timestamp is obtained from the local clock and is associated with the PCR sample value. The digital computer determines a line of best fit to a set of values including the PCR sample value and the timestamp, and previously received PCR sample values and associated timestamps. The line of best fit represents a reconstructed system time clock. The digital computer determines a PCR jitter value for the PCR sample value by determining a distance between the line of best fit and the PCR sample value.