HD491 Smart Encoder
Copyright © 2000-2014 EEG Enterprises, Inc. 22
All Rights Reserved.
HD Output Types
The HD491 is capable of outputting HD caption data in three different
ways. HD VANC Insertion implements SMPTE 334M-style encoding of
the caption data on to the output video signal. HD Serial Output puts the
caption data out onto P1 instead, for connection directly into an ATSC
encoder. HD Serial Output can be configured to use either the SMPTE-
333M or the Grand Alliance protocol.
HD VANC Insertion
In HD VANC Insertion, the Encoder inserts its CEA-708B caption output
data into the vertical ancillary space of the Master HD video source, using
SMPTE 334M protocol. The newly captioned HD video signal appears at
the HD-SDI video outputs on the rear panel.
VANC Insertion is the Encoder’s default HD output type and will be in
effect unless the P1 port has been set to the Grand Alliance mode. In the
default mode, the encoder will automatically switch to SMPTE 333M
mode if P1 is connected to an ATSC encoder supporting the SMPTE
333M protocol. The Encoder will return to VANC insertion mode if the
device supporting SMPTE 333M is disconnected. VANC insertion can
also be disabled by typing
<CTRL+A># OFF <ENTER>
. If insertion is
disabled through this command, it must be re-enabled using
<CTRL+A># ON <ENTER>
. The command to return to VANC
insertion from another mode, with automatic SMPTE 333M detection on
P1, or to change the VANC line on which insertion takes place is
<CTRL+A>f 334 [
Line
] <ENTER>
. To enter VANC Insertion mode
without automatic 333 detection, use
<CTRL+A>f vanc [
Line
]
<ENTER>
. This will allow P1 to be used as a general purpose serial input
port.
The
Line
parameter sets the VANC line on which caption data
will be
inserted into the HD video signal. Non-captioning VANC data packets on
that line will be preserved. The following table lists the valid VANC
insertion lines for the most common HD video formats. The Encoder’s
default insertion line is line 9, which is valid for all formats. Entering 0
as the Line parameter will set insertion for the first available VANC line,
using the order listed in the table below for each format. In interlaced
formats, caption data will only be inserted once per frame, in the first
field.
