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FS4 Frame Synchronizer/Converter v1.1
1.3 Downconvert
AFD dflt
This parameter selects what occurs when the Downconvert Mode parameter has been
set to “Auto AFD” (see
“7 Downconvert Mode” on page 76
) and no AFD codes are detected
at the selected input source.
2 Caption Xlator
This parameter translates closed captioning from the SD CEA-608 format on line 21 to the
HD CEA-708 format and inserts it into the output video stream.
NOTE:
This parameter interacts with parameter SD Line 21 Blanking, see below.
In standard definition video (525i59.94 or 625i50), closed captioning data is encoded and
sent on line 21 of both fields, using a format defined by the Consumer Electronics
Association standard, CEA-608. This is traditionally called “line 21", “SD”, or “608”
captioning, and is used for analog composite, analog component, and serial digital (SDI)
video.
In high definition video, closed captioning is encoded and sent as Vertical Ancillary
(VANC) packets in SDI video, using a format defined by the Consumer Electronics
Association standard CEA-708 (there is no equivalent for analog HD video). This is
traditionally called “HD,” “DTV,” or “708” captioning. The data formatting and encoding
for 708 captions is very different from the data contained in 608 (SD) captioning,
reflecting the added features and capabilities available with the CEA-708 standard.
When the Caption Translator is on, the FS4 Upconverter automatically translates
incoming line 21 captions to CEA-708 format and inserts the VANC packets into the
converted HD video stream. This is a complete translation from CEA-608 format to CEA-
708 format (including the embedded SD captions).
Hold Last (default)
Crop
Anamorphic
14x9
Letterbox
Hold the last setting.
Image is cropped to fit new screen size.
HD image is converted to full-screen SD with a 16x9 aspect ratio
(anamorphic).
Image is reduced slightly with aspect ratio preserved. Black is
added top and bottom, and the left and right sides are cropped.
Image is reduced with black top and bottom added to image area,
with the aspect ratio preserved.
Off (default)
When Off, caption translation is not performed.
On
When set to On, the FS4 will automatically translate incoming line
21 captions to CEA-708 format and insert the VANC packets into
the converted video stream. This is a complete translation from
CEA-608 format to CEA-708 format (including the embedded SD
captions).
