The cable industry is working to keep the Federal
Communications Commission from foisting new digital closed-captioning requirements that
could create compatibility issues affecting millions of set-top boxes.
At issue are proposed FCC rules covering the display of
closed-captioned text for digital broadcasts, delivered via digital-television receivers
or through digital-cable set-top boxes.
Cable vendors and the National Cable Television Association
are arguing in comments submitted to the commission that if the proposal is not amended in
several respects -- including technical compatibility with current equipment and the
treatment of digital programming under the new rules -- it could mean significant,
potentially expensive problems for operators and programmers.
"Closed-captioning is important, and we want to make
it work," NCTA vice president of science and technology Bill Check said. "It's
just a matter of trying to work through some of these issues."
Closed-captioning represents the audio portion of video
broadcasts, transmitted as encoded data in the signal and superimposed as text to help
hearing-impaired viewers follow TV programming.
FCC rules require broadcasters and some programmers to
ensure that they distribute captioned programming, with a phase-in period currently under
way to require all nonexempt analog and digital programs first shown after Jan. 1, 1998
("new programming"), to be closed-captioned by Jan. 1, 2006.
Since 1990, the FCC has required that TV sets with screens
13 inches or larger have integrated circuitry to decode and display closed-captioning
signals passed along by programmers.
Cable operators pass digital closed-captioning through
analog TV sets or a National Television Systems Committee-format set-top box, to be
decoded on line 21 of the vertical blanking interval via a Society of Cable
Telecommunications Engineers-adopted method called "DVS-157," which uses the
"EIA-608" standard for line-21 data services.
But in what it called a response to digital broadcasting,
the FCC issued a notice of proposed rulemaking in July to adopt technical standards
covering the encoding, delivery and display of closed-captioning information on digital-TV
The commission also proposed a transition plan to cover
phasing-in captioning for new digital programming.
"This will ensure that consumers who purchase DTV
receivers will be able to enjoy the advanced features of digital captioning," the FCC
In essence, the FCC is proposing to incorporate parts of
industry standard "EIA-708-A," a technology that defines how to support advanced
capabilities such as viewer-customized captions that might use a variety of fonts, colors,
character spacings, screen positions or even foreign languages.
That creates what the NCTA and set-top-box makers such as
General Instrument Corp. and Scientific-Atlanta Inc. believe is a major issue:
incompatibility with the huge existing base of digital set-tops that will be in the field
for years to come, even as more advanced boxes are deployed.
The NCTA and the vendors said the current DVS-157 mode
widely used by cable equipment is incompatible with the full EIA-708-A lineup of advanced
That could force cable operators to transmit captioning in
two formats. One would be readable via DVS-157 over digital-to-analog set-top converters,
and another by digital TVs compatible with EIA-708-A.
Alternatively, cable operators might swap out millions of
current-generation set-tops that would require hardware upgrades to read EIA-708-A
content, plus modifications to cable-headend elements.
"Where we had heartburn was trying to explain to the
FCC that what they were doing by mandating 708 carriage in 157 mode was basically
obsoleting 5 million-plus set-tops out there today," said Kevin Keefe, GI's director
of product management for digital-network systems. "You really can't or would not be
able to easily upgrade those to support the other mode."
Instead, the NCTA and vendors are arguing that a better
solution would be to amend the proposed new rules so that they mandate a digital standard
compatible with the current-generation DVS-157 already widely used by cable.
Keefe said the EIA-608 standard can support many of the
features of EIA-708-A, and it would maintain compatibility with DVS-157.
Bill Wall, technical director for S-A's subscriber-networks
business, said supporting the full slate of EIA-708-A requirements would become more
feasible as cable operators begin deploying the next generation of advanced set-tops, such
as S-A's planned "Explorer 6000."
Those set-tops will have high-definition-TV-decoding
capability and high-bandwidth Institute of Electrical and Electronics Engineers 1394
"fire-wire" connections that will pass through EIA-708-A content.
"Our position today is that anything that goes out on
an NTSC format has to be standard 608-type captioning or the digital equivalent,"
Wall said. "For stuff passed on a fire-wire output, we can do full 708, because we're
not doing anything but passing it through."
The FCC was taking further comments last week before its
deadline for responses today (Nov. 15), and it expects to have additional discussions with
manufacturers and cable operators about the issue, according to Neal McNeil of the
commission's Office of Engineering and Technology.
McNeil said it was too early to characterize the
commission's reaction to the industry's feedback. The rulemaking should be completed by
The NCTA also wants the FCC to extend its proposed timeline
for including digital programming under its captioning rules governing the requirements
for so-called new programming.
The FCC has given program networks one year after adoption
of new closed-captioning rules before they become subject to the current schedule for the
transition to captioning of all new programming.
The NCTA's comments argued that captioning of new digital
programming presents more challenges than analog captioning, especially given the lack of
equipment conforming to the new decoder standards and the need for networks and captioning
companies to acquire the equipment and to train workers to use it.