SCTE-65
Service Information Delivered Out-Of-Band For Digital Cable Television
This SCTE standard's Profile 6 is somewhat analogous to PSIP, the simularly numbered ATSC A/65 system informaton
(Program and System Information for Broadcast and Cable) specification.
For the longest time, there were few to zero cable set top boxes capable of
making use of this protocol, in favor of proprietary or Java-based interactive
cable programming guides. However, due in no small part to SCTE-65 being
referenced for tru2way interactive devices, an increasing number of cable set
top boxes have embraced SCTE-65.
The rest of this page only addresses SCTE-65 Profile 6.
While there are significant differences to the ATSC specification, several of
the metadata tables specified in SCTE 65 are identical in format to the
corresponding ATSC PSIP tables. As a practical matter, SCTE-65 uses a base_pid of 8188/0x01FFC, where PSIP uses
the base_pid of 8187/0x1FFB. The L-VCT (longform virtual channel table) in SCTE-65
is identical in syntax and semantics to the Cable Virtual Channel Table in PSIP,
it just travels on pid 8188 instead of 8187.
The main differences between SCTE-65 and PSIP are that the former uses Aggregate
Event Information Tables and Aggregate Extended Text Tables rather than PSIP's
Event Information Tables and Extended Text Tables. Also, the structure and
repetition cycles of the respective System Time Tables differ and there are
additional table_type code point in the Master Guide
Table. The same Master Guide Table that suffices for PSIP can also be
included in SCTE-65 when the presence of SCTE-65 Profile 6 tables are included.
However, not all the semantics for tables and descriptors in SCTE-65 exactly
match those in ATSC A/65 PSIP. In some cases, this has to do with the documents
being edited on different time scales, but other differences are quite
intentional. Besides the SCTE-65 system time table having a different form than
the STT in PSIP, the former accounts for daylight savings quite differently than
does PSIP (while using the same data elements and mechanism to signal daylight
savings time.)
In addition the form of the Program Map Table specified in SCTE-65 is effectively
indentical to the "cable version" of the PMT specified in PSIP for "cable."
The latest version of the SCTE-65 standard can be found here: (2008)
All EtherGuide Systems broadcast metadata generators offer dynamic,
isochronous SCTE-65 (Profile 6) output alongside ATSC A/65 (PSIP) output.
EtherGuide Systems is relatively confident in saying that we provide the first
metadata generator with this capability.
Please contact EtherGuide Systems for more details.
This page was last modified on August 12, 2010.
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