Tektronix MTX100A, User Manual

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Using the Menus
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MTX100A MPEG Recorder & Player User Manual
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Update: When you select this button, the following Select Update Item dialog
box appears. Use this dialog box to select which parameters in a stream are
updated when looped.
Continuity Counter: Sets whether to update continuity_counter. Press the
TAB button repeatedly to select this item, and then press the SELECT button
to toggle the check box on or off.
PCR/PTS/DTS: Sets whether to update PCR (Program Clock Reference),
PTS (Presentation Time Stamp), and DTS (Decoding Time-Stamp). Press the
TAB button repeatedly to select this item, and then press the SELECT button
to toggle the check box on or off.
Update Method: Specifies the method to update PCR/PTS/DTS. You can
select Software or Hardware.
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Hardware: PCR/PTS/DTS are updated using the counter values of the
27 MHz clock on the output board. Since data output and PCRs are
completely locked, the continuity of PCRs is maintained at the loop point
even if playing long stream loops. However, timing errors occur in
PTS/DTS.
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Software: PCR/PTS/DTS are updated by adding the actual looping time
(defined by the start and stop positions) to the stream every time it is
looped. There are no timing errors in PTS/DTS, however, it is difficult to
maintain the continuity of PCRs at the loop point because the updating is
not synchronized with the 27 MHz clock on the output board. Since this
method is used to update NPT, if you enable the NPT option, Software is
selected automatically.
Press the TAB button repeatedly to select the list box, and then press the arrow
buttons to select either of two methods.