and Forward Video
By Michael Murrie,
TBS contributing editor
Global Communications Talking Head GCS-750 Video Phone
Hughes RBGAN satellite IP modem with antenna lid weighs
1.6 kg and measures
column introduces a new TBS featurea regular review of
technical advances in the satellite television field byMichael
Murrie, professor of journalism and video production at Pepperdine
University. Murrie writes regularly about television news technology
for various professional and trade publications, especially
Communicator, published by the Radio Television News Directors
unwieldy production tools of television news seem to finally
be yielding to the efficiencies of digital video. Small DV camcorders
with three CCDs (charged coupled devices, light sensitive computer
chips) priced at a few thousand US dollars create electronic
images with quality that rivals the Betacam camcorders of a
decade ago that cost ten times as much. Off-the-shelf computers
including laptops edit video that rivals videos created by post-production
facilities costing fifty times as much a decade ago. Now innovations
in signal conveyance and compression offer more ubiquitous,
efficient, and economical alternatives to satellite news gathering
(SNG) with bulky uplink kits or vehicles.
innovations have been available for several years, but television
journalists in large numbers only used them seriously since
the Iraq war of 2003.
most significant are the store-and-forward systems for covering
vast regions with uncertain telecommunications infrastructures.
These systems combine the economies of compression and computer
editing to convey video using nearly any telecommunication means
available even if land phone lines or broadband satellite transponders
are unavailable. The scalable store-and-forward systems can
use satellite phones, Internet connections, and even wireless
to convey video. The bandwidth of the method simply changes
the time required to convey the video.
known as laptop news gathering (LNG) or digital news gathering
(DNG), typical systems start with a digital video camcorder
or videotape player linked to a laptop computer or other portable
computer to ingest and edit video. The resulting edited video
file is transmitted via the most appropriate telecommunications
link to another computer or video server on the receiving end.
Its decoder converts the data back to audio and video for recording
or display. The transmission time depends on the size of the
file and the bandwidth of the communication link. Some vendors
have proprietary boxes for encoding and transmission and for
reception/decoding. Transmission by satellite phone requires
a transmission device. Common compression methods include H.320,
MPEG-1, MPEG-2, MPEG-4, Windows Media 9, and Quicktime.
of store-and-forward systems include flexibility and low costs.
Disadvantages are limited bandwidth, format confusion, and sometimes
transmission costs. Because these advantages and disadvantages
often reflect two or more dimensions of the same characteristic,
let's examine them as they relate to the nature of the telecommunications
services and equipment, the costs, and the nature of digital
video. Also included is a short discussion of video phones and
cell phones as conveyors of news video.
earlier, the store-and-forward systems typically can be adapted
to almost any telecommunications signal conveyance method ranging
from POTS (plain old telephone service) to satellite phone services
to Internet Protocol services such as Regional Broadband Global
Area Network (RBGAN). The bandwidth of these services is improving
as new services become available and enhanced, but they fall
far short of the bandwidth of a conventional satellite feed.
For example, RBGAN can convey up to 144 kbit/s per second as
compared to the most efficient SNG transponders that send real
time MPEG-2 video at about three megabits per second. More often
the SNG rate is much higher.
the limited bandwidth of store-and-forward systems makes the
transmission of video much slower than real time, with perhaps
thirty minutes or more needed to transmit a one-minute reporter
package, depending on the data rate. Any video transmitted live,
usually by video phone, is small, of poor resolution, and has
a slow frame rate, as was evident in much of the breaking news
coverage of the 2003Iraq war.
the disadvantages of narrow bandwidth, the advantages of using
lower bandwidth telecommunications are ubiquity of service and
flexibility of logistics. Land-based phone service is available
in many parts of the world, but if unavailable, with appropriate
equipment and service, satellite phone service is available
from almost anywhere regardless of how remote or undeveloped.
Yet there are times when even the satellite phone telecommunications
infrastructure becomes overburdened with traffic from certain
parts of the world. Before the Iraq war in early 2003 there
was "great trepidation about the competition for Inmarsat
channels" among the networks as they made their war plans.
Inmarsat addressed capacity issues by placing a backup satellite
in service to handle the extra traffic. Bill Tracy, director
of ENG for ABC News, said he was "pleasantly surprised
with the results" (Murrie 2003).
service is expanding in the Arab World and other nearby regions.
It currently serves ninety-nine nations in the Mediterranean,
Middle East, Europe, the Indian subcontinent, and North, Central,
and West Africa. Just last month Inmarsat reached agreement
with Net Iletisim of Turkey and Cerist of Algeria to broaden
the marketing of RBGAN. Plans by Inmarsat and the European Space
Agency call for extending BGAN service in 2005 to provide data
service at speeds up to 432kbits/s.
size of store-and-forward systems creates an independence of
movement and political regulation. Often a news crew entering
a nation must have special approval for satellite uplink equipment
thus making the crew vulnerable to regulators and extraordinary
fees or taxes. The store-and-forward systems attract less attention.
They usually reside in a laptop computer. A RBGAN satellite
IP modem including antenna is similarly sized typically weighing
1.6 kg and measuring less than 300 x 300 x 50 mm. Satellite
phones typically have the same width and depth with a height
of perhaps 150mm. SNG transponders are getting more compact
now-they are comparable to large suitcases-but even the smallest
measures 70 x 50 x 30 cm.
feature of the RBGAN service is that its charge is by data unit
transmitted, typically $10 to $15 US per megabyte, according
to Inmarsat. The connection can remain on and does not necessarily
need to be re-established from the same transmission point.
The user simply connects the modem to a laptop computer, points
the antenna in the direction of the satellite and begins communication.
than charge for data transmitted, conventional Inmarsat phone
service charges by the minute regardless of whether data is
transmitted. High speed GAN service of 64 kbit/s costs from
$6 US per minute. Sometimes two or more channels are combined
to produce higher data rates.
Given long transmission times, it's quite possible that just
the transmission costs for sending a two-minute video story
in real time via broadband satellite could be much less than
taking an hour or two to send two minutes of video via a satellite
hardware costs are much more for conventional SNG. Uplinks cost
at least $100,000 US and often much more. Satellite phones and
IP modems are much cheaper. RBGAN hardware expenses are even
less, with a modem cost of less than $2,000 US. A GAN modem
terminal tends to have more robust signal strength but costs
$7,000 US. The cost of a videophone GAN terminal with a single
channel of 64 kbits/s is $8,000 or with two 64 kbits/s channels
$10,000 US. Store-and-forward software for a laptop computer
starts at about $2,000 US as does the price of an appropriately
configured laptop computer itself.
us to another important point about the store and forward systems.
Although the IP modems, satellite phones, and videophones are
special items, the basic laptop that often contains editing
and transmission software is off-the-shelf. Thus chances are
good for repair, loan, or replacement in case of hardware failure.
on computers seems to come in an unending variety of formats,
both proprietary and open. Fortunately, quality and efficiency
continue to improve as vendors develop more systems that handle
multiple formats. For example, the Livewire Digital M-Link platform
for its Voyager Lite store-and-forward system incorporates video
codecs such as Microsoft Media 9 and other derivatives of MPEG-4
while maintaining options to use MPEG-1 or 2. The laptop editor
must have IEEE-1394 (Firewire) inputs to accept DV video. The
editor must edit a high quality video file acceptable to the
television system at the destination site.
phones offer field crews versatility and mobility to convey
live video but do so at a slow frame rate and much less resolution
than SNG uplinks. Compression methods are most often those employed
for video conferencing such as H263. Usually the video phones
use GAN ISDN service that is 64 kbits/s or paired circuits at
128 kbits/s. The arrangements usually include an IFB signal
back to the video phone.
products are becoming available that promise better signals
than those from videophones. For example, Quicklink's Live Broadcaster
codec is scaleable so that it works from anywhere between 64Kb/s
to 4Mb/s. Latency over the Inmarsat network is approximately
has recently started using 2.5G cellular phones from Nokia to
deliver video from the field (Kerschbaumer, 2003). Video quality
is comparable to a single channel satellite phone but can only
be used for store-and-forward not live reports. A phone can
store 128MB of data or about two minutes of audio and video.
Transfer time is about 20 minutes for 70 seconds of video at
only 15 frames per second and the highest resolution.
systems and videophones extend the reach and presence of news
organizations in the field. Just considering capital costs,
for the price of one flyaway SNG uplink, a news organization
can deploy several store-and-forward reporters each with a laptop,
DV camcorder, and satellite phone and/or IP modem. These crews
can go to more remote locations. Transmission costs may be higher,
but they can operate more efficiently as one-person crews saving
personnel costs. An SNG flyaway would usually require at least
a technician and a reporter. With less bulky equipment the laptop
news gatherers are more mobile and may be less vulnerable.
Over time, because of the economy and ubiquity of digital news
gathering, more stringer material from more diverse locations
may appear on news programs. If cell phone operators begin contributing
video, the news gathering process will open dramatically. The
BBC is already considering how to take new content from a new
class of video stringers (Kerschbaumer, 2003).
open news gathering process, of course, raises concerns about
the accuracy, fairness, and credibility of news video from stringers.
What processes can be established to verify such video?
It's doubtful that the low-cost digital video from laptop journalists
and cell phone users will soon replace SNG uplinks for live
coverage. They will still be needed for higher quality, more
complex news programs on location. Laptops and even cell phones
are just additional tools that can be used to gather more diverse
stories, more quickly from a broader range of sites. TBS
D. (2003) New compression technologies aid war reporting, save
cash. Transnational Broadcasting Studies 10 (TBS 10).
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C. (23 April 2003) TV goes to war. TV Technology. (http://www.tvtechnology.com/features/news/n_TV_goes_to_war.shtml)
(22 Dec. 2003) "News Video Gets Mobile" in Broadcasting
& Cable, Vol. 133 (51), p. 14
M. (May 2003) "New Technology Brings Live Coverage of War
in Iraq" in Radio Television News Directors Association
Communicator, pp. 6, 8.