Instruction manual

HDE-3000 - 78 -
Appendix A. Discussion of HD Captioning
Definitions
SD = standard definition video (NTSC and PAL).
HD = high definition video (1080i, 1080PsF, 1080P, and 720P).
VANC = the vertical ancillary data area in a video signal.
HANC = the horizontal ancillary data area in a video signal.
Introduction
Closed captioning for HD represents a new paradigm in closed captioning. Instead of
encoding the caption data as an analog waveform into a dedicated video line (21 for NTSC,
22 for PAL), HD caption data is encoded as ancillary data packets in the VANC area of the
video. Along with the caption data, the VANC area may contain several other types of
ancillary data packets.
The Important Specifications
EIA-608-B specifies SD line 21 caption data authoring, encoding, and decoding.
EIA-708-B specifies HD caption data authoring, encoding, and decoding.
SMPTE291M specifies ancillary data packet formatting.
SMPTE334M specifies the formatting of caption data into ancillary data packets to
be encoded into the VANC area of the video.
SMPTE RP168 defines the switching point for synchronous video switching
(referenced in SMPTE334M).
SMPTE274M specifies all of the 1080 I and 1080 P formats.
SMPTE RP211 defines the 1080 PsF (progressive segmented frame) formats.
SMPTE296M specifies all of the 720 P formats.