HD491 Smart Encoder
Copyright © 2000-2014 EEG Enterprises, Inc. 24
All Rights Reserved.
XDS Insertion
Extended Data Services (XDS) is an NTSC Field 2 data channel that
provides information to viewers about the program that is being aired.
XDS is used to transmit FCC-mandated program ratings to allow viewer
V-chip filtering. XDS is a part of the CEA-608 standard for SD
broadcasts, and should be included in the 608 compatibility bytes of
CEA-708 compliant HD broadcasts.
The 491 Encoder includes all of the XDS functionality of the broadcast
industry’s leading XDS solution, the EN470 Smart Encoder III. XDS data
packets can be loaded into the Encoder’s queue with one simple
command, and be held for any specified time period. Each individual
packet type can be independently set for upstream or local priority, and
permanent packets can be stored in Non Volatile Memory and inserted
automatically whenever the Encoder is operating.
Packets are inserted into output video signals using EEG’s proprietary
Stochastic Scheduling Algorithm. The Stochastic Scheduling Algorithm
is a finely tuned solution to the Field 2 bandwidth limitations that cause
difficulties in XDS packet transmission. A Priority level is automatically
assigned to each packet based on its XDS Class and Type. The Stochastic
Scheduling Algorithm ensures both that high priority packets like V-chip
data and program names are transmitted frequently enough to be instantly
accessible for new viewers, and that lower priority packets are guaranteed
to be inserted periodically, and not preempted completely.
As per CEA-608B specifications, all available Field 2 space is filled,
rescheduling and regeneration are automatically performed on all
upstream packets, and packet continuations are applied when necessary.
Additionally, upstream XDS program packets will continue to transmit
for five minutes after any non-clearing upstream interruption, such as a
commercial break or undesired outage.
Enable XDS Entry
<CTRL+A>O XDS O <ENTER>
This command must be entered to enable a port for XDS input. A port
must be enabled for XDS input in order to accept XDS data and control
commands. The character repeated in the command is a capital o and
not a zero.
