Abstract- Congress has passed the Television Decoder Circuitry Act of 1990 and the FCC has issued rules requiring 13-inch and larger television receivers manufactured after July 1, 1993 to include decoder circuitry to display closed captioning data1. Manufacturers are busy preparing products for introductions in compliance with this new requirement. The EIA's Television Data Systems Subcommittee has been working at the request of the FCC to develop standards for extended data services on line 21 of field two, which will make use of the same decoding hardware.
Because of the certainty of the required decoding circuitry, an opportunity was created that guarantees widespread availability of a new data communication channel from the broadcaster to the TV receiver. The resulting new features will make TV receivers more user friendly and create new opportunities for broadcasters.
In September of 1990, a group of TV receiver manufacturers and caption providers* formed a Task Force under the Electronic Industries Association (R-4 TV Systems Committee) to formulate the TV receiver display standards for Closed Captioning. This group worked assiduously to deliver a document to the FCC by December of the same year. With minor modifications that document was incorporated into the FCC Report and Order of April 15, 1991 which defined the requirements for closed caption decoders that must be part of every TV set manufactured after July 1, 1993.
The same group became the EIA R4.3 Subcommittee: "TV
Data Systems" and has since been working at the request of the FCC2
to define Extended Data Services for line 21 of field 2.
In addition to adding the capability to provide a second, independent caption service with all the same features as the original, several new features will be added.
The second (field-2) service will be able to provide complete
captions in a second language, with all the necessary special characters
without being restricted by the presence of the original captions. Additional
character symbols will be included to allow support for many languages
not now supported. New options will be added to allow caption providers
to select a variety of background colors.
The new service will add the capacity to provide two additional
TEXT services in the same format as the current service.
A completely new service will be added to allow program providers and local broadcasters to transmit data which can be used to describe numerous aspects of the current and future programs. This new service will also be capable of sending automatic station identification, clock setting data, aspect ratio information, and National Weather Service text messages.
What are the Benefits for TV Viewers? There will finally be an end to the blinking on VCRs and TV screens. Automatic clock setting, with self calibration, will permanently end this problem.
Channel Maps that list which station is on what channel will no longer get misplaced or clutter the coffee table. No matter how often the local CATV company shuffles the line-up, viewers will always be able to find their favorite stations by on-screen station identification and channel selection.
Channel browsers will be able to identify the name of programs quickly by on-screen program titles that are generated by the TV. These titles can even appear during a commercial break. Figure 1 below, illustrates an example of how a browsing screen might appear:
Fig.1 An example of a Browsing Screen
In addition to information about the current program, stations will also be able to send their schedule for upcoming programs. The receivers can be made to seek and store this information during non-use and compile it into an on-screen program schedule. This information can be used in on-screen displays to make program selection quite easy. Figure 2 shows how this might be displayed.
Fig.2 An example of an On-Screen Guide display.
A second screen could be used to view more detailed information
about the current or scheduled programs. Figure 3 shows how this might
look.
Fig.3 An example of a Detailed Program Listing.
Information about the program's aspect ratio is also included so new wide-screen TVs can automatically zoom in to fill the screen on letterboxed programs or commercials.
The system also provides VCR users with a number of features. Since each program is uniquely identified, VCRs can be designed to record desired programs completely, even if they run overtime or are delayed. Program identifiers for future programs can be transmitted during previews so VCRs can be instantly programmed by impulse response.
The system will also have the means to retransmit the National Weather Serviceís Weather Radio Specific Area Message Encoder (WRSAME) messages. This capability would allow TVs to use on-screen displays to show weather warnings for their specific area as quickly as they are issued.
What are the Benefits for Broadcasters? At last the broadcaster will have the means to identify his station by call letters (and network affiliation) directly on his viewers TV screen whenever channels are changed. CATV operators will no longer be able to confuse consumers by re-mapping channels.
Program providers will be able to fully utilize the wide-screen modes of new wide-screen TVs by controlling when the TV switches into the various modes.
Channel browsers will be captured by advertisers when they see the name of the program they are interested in viewing. Ratings can be improved because it will be easier for viewers to find the programs they want to watch or record.
These new data signals will be transmitted exclusively on line 21, field 2 in the same format as closed captioning signals. The new signals may coexist with the new closed captioning services & text services also planned for this line.
Until now, this line has been reserved but unused. Currently there is a FCC authorization3 to place a 9 bit pseudo random framing code signal here. This signal is supposed to occupy about 1/2 of this line when Closed Captioning signals are transmitted. It should be made clear that this signal has never been used by any captioning equipment.
The EIA Subcommittee will be making a recommendation to the FCC for authorization and protection of these new services on line 21, field 2.
There have been many similar and competing proposals for
program identification schemes in recent months. Many of the other proposals
offer higher data transfer rates and more capabilities. However, there
are several advantages that are only available on the EIA system.
What are the Hardware Advantages?
The receiver hardware comes for free. All the hardware
requirements for this system will be included in every TV manufactured
after July 1, 1993 in order to comply with the closed captioning requirements.
Receiver manufacturers have championed this cause to provide a low-risk
solution. Only some additional control software is required beyond the
minimum caption decoding and display hardware that will already be included.
The encoding hardware is almost free. Since the encoding
equipment needed is exactly the same as the equipment used for encoding
the closed captioning signals, many stations may already have this equipment.
Because of the increased exposure and more widespread use of captioning,
new encoder suppliers will have more equipment available at lower costs.
Again the only difference to this equipment is some additional software
to automate the transmission of the codes.
What is the Format Advantage?
Because this system is defined as part of the extended
services for the line 21 closed captioning system, it is expected that
it will gain the same FCC protection as the current captioning system.
This protection ensures that the data is not removed or destroyed by down-stream
processes. There will only be one type of signal on line 21.
Why not Other Proposed Systems?
It would be unlikely for receiver manufacturers to embrace
a different system that involves additional hardware costs. Why should
one build a new data decoder for a system that may never materialize or
get widespread support?
Program providers or local stations have no incentive to transmit data to an audience they are uncertain will ever exist. This creates a question of which comes first, the data or the receivers? The EIA proposal faces no such uncertainty, all the hardware will be in place.
As it now stands, caption decoding hardware will be in every TV (13" or larger) after July 1, 1993. The goal of the EIA subcommittee is to make the submission to the FCC by the end of the second quarter of 1992. Allowing 6 months for FCC action and finalization of the EIA specification, manufacturers could then begin adding the necessary software updates to TVs.
It would then be possible for some Program ID capable TVs and VCRs to appear by late 1993 or early 1994.
TV manufacturers, caption providers and other industry representatives have joined forces in an EIA subcommittee to establish a single standard for transmitting program and station identification data on an unused portion of the vertical blanking interval. This proposed system will allow many advanced, new features to both TVs and VCRs at little cost to the consumer. Broadcasters can benefit by providing the data which allows viewers to more easily find their favorite programs. This system is very likely to succeed because it will require no new hardware at either the transmitter or receiver ends. Broadcasters are encouraged to recognize the new business opportunities that will be offered and participate in the process that can make the current schedule for implementation of these program identification services a reality by the end of 1993.
I would like to express my appreciation for the dedicated
work and encouragement of the following individuals for their part in the
Task Force and on the Subcommittee: (1) Mr. Julius Szakolczay, Engineering
& Development Manager for Mitsubishi Electronics America Inc., and
Chairman of the Task Force and Subcommittee; (2) Mr. Tom Mock, Director
of Engineering EIA CEG and all those on the Subcommittee who have contributed
their valuable ideas and efforts to this new system.
Mitsubishi, J.V.C., Matsushita (Panasonic/Quasar), Philips (Magnavox), Samsung, Sanyo, Sony, Thomson (RCA/GE) and Zenith.
EEG and NCI.
Caption America, The Caption Center (WGBH), Real-Time Captioning
Texas Instruments, Gemstar Development Corp, Insight Telecast, E.I.A., N.A.B., and NCTA.
For comments or questions please send e-mail to: David Broberg: dbroberg@hotmail.com