Kramer Electronics SP-14 - Manual (Page 20)

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4.6. Time Code Settings
SP-14 processes time code information from SD formats on the analogue Composite, S-Video and
Component inputs. For 480i/NTSC lines 14/277 and 16/279 are scanned for time code (VITC). For
576i/PAL lines 19/282,21/284 are scanned for time code (VITC).
Also, time code information from SMPTE RP-188 ancillary data packets (DID = 0x60, SDID = 0x60) on
the 3GSDI inputs is processed. The packets are tagged internally with the associated incoming video
frame, then sent out again on the 3GSDI output (only) when that frame reaches the output. Note that
the frame-count part of the time is regenerated as per SMPTE 12M. Missing/corrupted input packets get
replaced and frame-count on the output will match the output format.
Time Code Output
SP-14 allows to specifically switch off that time code information.
TC Source Select
The time code source can be either “Current Input' or ''Free-Run”, i.e. internal generation.
When “Current Input' mode is selected, the output time code will track the input received from the
current video source. If that input consists of a series of clips with time code discontinuities at start of
each new clip, then the output will change to match. If the input player is paused at any stage, but still
outputting valid time code, then the SP-14 output time code will also be paused.
Note that the output tracking allows for differences that can arise as a result of either one of input or
output being in 'NTSC time'. If the video format is 23.98Hz, 29.97 or 59.94Hz, then the associated time
code will run slightly slower by comparison with real time, and is known as 'NTSC time'. If
“Drop Frame
Mode ” is enabled, then this is compensated for by skipping two frames every minute, so the error is kept
small.
If the currently selected video input channel hardware does not support time code (DVI, HDMI,
Analogue, and Test Pattern) then the TC source selection option will say 'N/A' (not available). If time
code input is supported by the video input channel hardware (CVBS 1/2, S-Video, 3G-SDI 1/2, and Y-
CbCr) but there is no time code being supplied from the video source, then the output will just free-run.
If time code is seen for a while at the input, and then it stops, the output will continue, but free-running
based on the last time code seen.
When
“Free-Run” is selected, then the time code output will be generated inside the SP-14, but can be
reset to any start value by the user, as required.
TC Load Trigger Mode
This menu item is used to select
how the reload process happens. “Free-Run Manual” means the output
is changed immediately on demand whenever the user chooses “Time Code Load Now” in the menu.
The 'Synchro' options
under “TC Load Trigger Mode” require the current video source to also have time
code attached, so when the input time code matches the “Timecode Input Trigger” value, the output
time code will be the “TC Output Load' value. The different options provide several alternative ways of
specifying how much continuous pre-run time is included in the output time code before the trigger point
is reached:
-
“Synchro Auto” will start pre-run as soon as the input time code has been stable for 5 seconds
- “Synchro Prerun” will start pre-run at the offset entered by the user for the “Timecode Prerun Period'
- 'Synchro Manual' will wait until the input time code has been stable for 5 seconds and then the user
can start pre-run at any point until the trigger time by choosing
“Time Code Load Now” in the menu.
TC Input Trigger
Set time code input trigger value for synchronisation of the internally generated time code with the time
code provided by the video source.
TC Prerun Period
Set output time code pre run period.