Monday, January 27, 2014

The Evolution of News Gathering: ENG, SNG, and Digital Broadcasting



When you turn on the TV to catch the local news, it’s easy to overlook all of the steps required to get the picture you’re seeing from the news truck to your TV.  These include initial video/audio capture, signal encoding, and transmission back to the station, decoding, editing, re-encoding and re-transmission to your set. Within the industry, this process is known as ENG or Electronic News Gathering (an industry term for the use of video technology to allow live reporting from remote field locations).

Closely associated with ENG is SNG (Satellite News Gathering). Whereas ENG typically relies on local microwave links to transmit audio/video data from regional field locations back to the studio, SNG makes use of satellite links to distribute data to distant locations. Between them, ENG and SNG allow local TV stations to provide live coverage of news events anywhere in the world.

Just as magnetic tape technologies replaced older film technologies in ENG news reporting, ENG no longer captures video data in analog form on magnetic tapes but in digital form as arrays of pixels. These can be compressed for file storage and transmission and decompressed for editing and viewing. While digital technology has many advantages over its analog predecessor, including the elimination of ghosting, snow, and other types of signal interference, the most significant difference is simple economics. Because digital data can be highly compressed, it is possible to transmit better pictures and sound using less bandwidth, and to store images and sound more compactly. The bottom line here is lower costs and higher quality – a double win that quickly made digital technology ubiquitous in the TV industry after its introduction in the late 1990s.

But the digital revolution that began in the last decade of the 20th century is far from over in the second decade of the 21st century. The drive to reduce costs and improve quality continues today with, if anything, increased urgency as traditional broadcasters compete with an ever-broadening range of audio/video services available to consumers on smart phones, tablets, notebooks, and other screens connected to a wide variety of wireless and wired networks. For example, many broadcasters are now aggressively moving to adopt inexpensive, universally available Ethernet technology for signal transmission over IP (Internet Protocol), replacing older dedicated broadcast network standards like SDI (Serial Digital Interface) and ASI (Asynchronous Serial Interface).

Telairity gear has been designed from the beginning to help broadcasters stay competitive by providing the industry’s most cost-effective equipment for digital video compression, transmission, transcoding and de-compression. From the beginning, Telairity encoders have provided not merely traditional SDI and ASI interfaces but also Ethernet outputs as standard features, so broadcasters could move to adopt IP technology whenever ready without either the expense or the disruption of replacing or upgrading existing equipment.  Most recently, in 2013, we added a built-in modulator to our ENG line of encoders, eliminating the need for a separate piece of gear to generate radio frequency signals for transmission over a microwave or satellite link – an integration that not only reduces costs for our customers but also saves space in a crowded ENG or SNG truck.

In 2014, there will be lots more improvements in Telairity gear designed to help broadcasters reduce costs and improve quality, ranging from incorporation of new compression standards like HEVC to new, portable form factors that reduce cost and lower power consumption. Be sure to check back for more discussion of industry trends, and hear about our latest insights and solutions.