Crystal Vision
Data packet management
TANDEM-200 User Manual R1.7
17
13/02/2008
2 Data packet management
Ancillary data can be placed in both the vertical and horizontal blanking intervals of the
serial component video signal (SDI).
The VANC or Vertical ANCillary data space is used for ancillary data such as VITS or
vertical time code whilst AES/EBU digital audio data is embedded within in the
horizontal blanking data interval or HANC.
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Vertical ancillary data - VANC
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Active video
field 1
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Active video
field 2
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Vertical ancillary data - VANC
Vertical ancillary data - VANC
Vertical ancillary data - VANC
SW
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There is room for four groups of AES/EBU digital audio between the end of active video
(EAV) and the start of active video (SAV). A group is comprised of two AES/EBU stereo
signals or four monaural channels.
Each TANDEM-200 ‘side’ can de-embed up to four additional audio channels from one
of the four groups of its SDI input stream and can embed four audio channels into one of
four possible audio groups in the output SDI stream.
The following ancillary data handling options are provided:
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Support for contiguous HANC data packing
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Automatic mark audio group for deletion
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Blank entire HANC data space, except the EDH insert before embedding
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Wide range of formats to embed on all HANC lines or leave a gap around the
vertical switching point
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Variable error masking and error handling
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Enable or disable EDH processing
