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Keep Your Codecs Straight

This PowerCaster model of Winnov''s
XstreamEngine2 Advanced Encoding Solution delivers realtime encoding of audio, video, and rich media at various bit rates over IP networks. At NAB 2006, Winnov introduced CBOX 3, which can record and simultaneously broadcast dynamic PC content live in Windows Media Video (WMV), Microsoft''s version of SMPTE VC-1.

What if it was cheap to distribute video yourself and easy to set up? As a potential business, it's a fast growing market. According to In-Stat Principal Analyst Gerry Kaufhold, professional video over Internet Protocol TV (IPTV) is expanding dramatically. “The market for IP video equipment will top $2.6 billion by 2009, just for the consumer segments,” Kaufhold says.

Besides the potential of video over the Internet, thousands of schools, businesses, and churches regularly use their own video networks internally.

But until recently, running video and audio over such a network was tough to pull off. Why? RF-modulated analog video, a common solution that's still in wide use, can be expensive to set up and technically challenging to maintain. It also suffers from limited, VHS-level resolution. And what about two-way interactivity? Forget it. Many such installations simply make use of another analog technology — a telephone line — to return audio.

But over the last decade, the introduction of MPEG-based hardware (MPEG-1 became a standard in 1992) slowly started to solve the problem of delivering good-quality video over closed networks that a business might use, for example, to deliver training. Buyers of MPEG-based systems, however, still faced outlays for gear including servers, encoders, and decoders to send video to computer screens and television sets.

NAB 2000 changed all that. “At the show, you saw the first practical, dedicated AV hardware that employed IP technology,” says Joe Mendonca, director for streaming and video over IP solutions at North Haven, Conn.-based HB Communications. “This dramatically changed the way we could move audio and video over a network, simplifying installation and making it easy for our customers to use.”

What changed? Although streaming video over the Internet was possible via a new generation of PC cards, the actual video and audio compression was still very compute intensive, making realtime use impractical and production-time-consuming. But by the end of the '90s, improved technology such as DSP chipsets had enabled realtime compression of video and audio signals.

Combining that compute power with TCP/IP (the technology behind data transmission over the Internet) means that video and audio can be just as flexible in their distribution as anything else that goes over the Internet.

There are further benefits. Since IP gear can use the same Ethernet networks that already exist in many of today's businesses, schools, and other institutional settings, there's a built-in distribution network. That networking technology is far cheaper and easier to deploy and manage than single-use cabling such as the coax used by RF-based video distribution systems.

Today''s IP-based distribution gear isn''t just for video. At the University of Massachusetts, VBrick products are used to supply information—still text and images—to a campus-wide digital signage system. While the campus still uses an installed RF-based system to transmit video, it doesn''t have a future, according to John Jessoe (pictured above), director of the Distance Learning Video Production Center at the Boston-based university. “We need a system that one day we can also use to stream video to the desktop, do interactive learning, and more, so products like those from VBrick future proof our investment,” Jessoe says.

VBrick


Since its beginnings in 1997, VBrick ranked among the very first companies to develop both the codec hardware and software necessary to deliver MPEG-based streaming of full-motion digital video across a LAN or a WAN (wide area network).

VBrick quickly gained market share with its trademark “bricks,” compact encoders, decoders, or combo units that simplified I/O management with a variety of network connections, ports for cameras and remote control, and built-in apps that include two-way conferencing, video streaming, and signage. The Wallingford, Conn.-based company describes its gear with terms such as “EtherneTV” and “appliances” to emphasize their plug-and-play simplicity.

If you want a plug-and-play Internet video product, however, it might be best to go conservative.

“VBrick's technology is known for reliably working over a wide range of networks and types of transmission,” says Mendonca, who recently managed the install of a campus-wide TV network at Brown University, which mixes MPEG-2 (campus intranet) and MPEG-4 (commercial TV to students at dorms and apartments) delivery.

By closely conforming to published standards from its first product, Mendonca says, VBrick didn't run into the problems some other vendors faced when they got inventive, taking those video standard's guidelines as a recommendation, not a rule. “When users found that products [from other suppliers] didn't work well with all of their other gear, [those suppliers] lost business,” he says.

Last fall, VBrick added Windows media audio and video support to its lineup: The VB6000 WM Appliance functions as both an encoder and Windows media server. Using a similar compact, 1/2RU form factor as VBrick's MPEG EtherneTV appliances, the VB6000 delivers live streaming to Windows Media-enabled computers. Unlike MPEG-1 and MPEG-2 products, the new device enjoys a key benefit: Since it's compatible with the Windows Media Player, there's no need to install a separate desktop player.

Winnov


Closed television networks like Brown University can benefit from moving to IP-based networks that use one or perhaps two codecs. But what if your project calls for streaming from a location, where it's necessary to create multiple bit-rate video and audio streams in realtime?

You might want to consider gear from another vendor, Winnov, one of the pioneers in Windows Media development. The company's XstreamEngine2 (XE2) could be ideal for live production use.

According to the Santa Clara, Calif.-based company, XE2 is the only encoding solution on the market to ingest up to eight distinct video inputs in a single, compact unit, and then simultaneously stream multi-format broadcasts in realtime at various bit rates to thousands of users at the most optimized resolution for their device, whether dial-up, cellular, PDA, desktop, or set-top box.

Winnov started shop in the early '90s as one of the first developers of codecs and other technology for Windows-based audio and video delivery. According to CEO Olivier Garbe, Winnov not only worked with Microsoft to develop the initial PC multimedia codecs, but also notched a number of its own firsts, including delivering the first PC card — the Videum AV in 1996 — to offer synched, full-duplex audio and video, and creating the first turnkey Internet broadcast “studio in a box” — Videum StreamEngine — in 1999.

“Streaming using Windows Media has many advantages over either MPEG-2 or MPEG-4,” Garbe says. With Windows Media built into PCs, which dominate the corporate world, there's no need to install special player software or decoder gear. WM also adapts to a wide range of transmission parameters. “With the same equipment, you can stream to someone who has a cell phone or a 56K connection just as you can to a 300KB one. [WM] is easily scalable, while MPEG-1, -2, and -4 are not.”

Windows Media helps deliver practical, low-cost solutions in a variety of environments, such as solving traffic headaches for California drivers, according to Garbe. Working with the Alameda County traffic agency, Winnov placed four cameras under a number of traffic lights on the most congested roads. The IP-based cameras send video to centralized servers. Now, anyone wishing to get a realtime view of just how bad the traffic is just needs to log on to the website www.smartcorridors.com to see for themselves.


Keep Your Codecs Straight


Although most media is encoded into one of four codecs — MPEG-1, MPEG-2, MPEG-4, and Windows Media/VC-1 — other codecs are in the wings. Keeping track of codecs can be a full-time job. Here's a short list of the most frequently used codecs with some details about their applications.
— Jan Ozer

Adobe Flash 8


Default resolution: highly scalable and flexible.

While it's mostly been used to author web animations, Flash has become a viable, easy-to-use video and audio codec that could find wider use. The latest version has a couple upsides: Adobe claims the Flash codec is installed on the vast majority of web-enabled PCs, and there's an estimated 1 million Flash developers around the globe. Released last year, Flash 8 employs an entirely new codec developed by On2 Technologies. With visuals that compete with or even best that of established codecs, it delivers a smaller comparative file size than the others, even while supporting capabilities such as 8-bit Alpha (transparency) files and interactivity.

MPEG-1


Default resolution: 320×240 square pixels (computer screen) or 352×240 (VideoCD) streams at up to 1.5Mbps.

With VHS quality, MPEG-1 is the simplest of the MPEG standards, and all major operating systems include free MPEG-1 players.

MPEG-2


Default resolution: 720×480 at 4:3 aspect ratio. It can scale to 1920×1080 for 16:9 HDTV and for HDV camcorders such as Sony's HDR-FX1 and Canon's XL H1.

MPEG-2 is the common digital video transmission and distribution standard, but it's also used in editing and for DVDs. Looks best at data rates of 6Mbps to 8Mbps for DVD movies and 15Mbps for cable and satellite; works well on intranets, but it's too bandwidth-hungry for use on the Internet or over less reliable intranets. Unlike MPEG-1, not all computers can play MPEG-2 without a third-party plug-in.

H.264/MPEG-4 AVC (Advanced Video Coding)


Default resolution: typically 176×144 to 320×240

It scales down to fit on cell phones; QuickTime uses it, along with Dolby Laboratories' Advanced Audio Coding (AAC) codec as the default compression scheme for the iPod. Ideal for interactive applications, it works across a wide range of internal and external networks and over good or spotty connections. But the standard, which took years longer to ratify than expected, to some eyes, doesn't deliver as good a visual result when compared to newer or proprietary codecs.

Windows Media/VC-1


Default Resolution: 160×120 to HD

Windows Media is used to encode SD and HDV video. It's also been selected by SMPTE as part of the high-definition DVD standard (HD-DVD), so it will appear on many future HD-DVDs, including all those released by Universal Studios.

After SMPTE ratification, the core components of Windows Media were published as an open standard, VC-1. This allows manufacturers to build, for example, chips for set-top boxes and cell phones, and not worry about Microsoft changing the codec's parameters at a moment's notice.

RealVideo


Default resolution: 160×120 to HD

Though generally regarded as the highest-quality codec, RealVideo has two major faults, at least as perceived by the market. First, unlike the MPEG codecs and Microsoft's VC-1, it's not a standard. Second, it's not free and server fees get quite expensive at high stream counts.

QuickTime


Default Resolution: 160×120 to HD

QuickTime is more of a “wrapper” than a codec, since it can capture, edit, and stream a number of codecs. Apple came late to the streaming market, but it has offered a number of popular codecs within its architecture, including the aging but still popular Sorenson Video 3 codec, and MPEG-4 and H.264.


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