Pick up just about any technical publication these days and it's hard to miss the good news about the H.264/MPEG-4 AVC video standard. Yes, AVC is a powerful new platform that allows high quality video to be delivered using about half the bandwidth of previous technologies. And, because it offers such remarkable benefits, it's been embraced by virtually anyone and everyone concerned with the distribution of video content.
However, while acknowledging its legitimate benefits, the standard has become a catchall for a myriad of potential applications. From personal computers to handheld consumer entertainment devices to HDTV delivery to the home, the H.264/MPEG-4 AVC video standard is a far-reaching, universal solution that allows content distributors to create new business models and additional revenue streams within limited, existing bandwidth capacity.
For broadcasters, the big question is: How does it benefit me and where does it fit in a professional television facility?
MPEG-2 video compression has been around for around 10 years and has served the industry well, but MPEG-4 AVC looks to change the way digital video programs are stored and distributed. Driving this new technology is the financial and application dependent benefits of increased efficiency and the ability to deliver video at half the bit rate of current MPEG-2 methods.
With the recent explosion of interest by consumers in HDTV, the H.264/MPEG-4 AVC standard has quickly become a leading platform to deliver HD programming via satellite-to-home, video-over-DSL, IP networks, and in point-to-point systems. Many of the world's leading pay television operators--cable, satellite, and telcos--have recognized the clear path to future growth and are currently working to design systems based on the standard.
The convergence of IP and broadcasting technologies has resulted in an increase in the use of IP networks to deliver video for a new level of multichannel services. IP networking and packet-based delivery offers ease of use and flexibility, benefiting both fixed and temporary links. This latest-generation IP technology can securely deliver video over the public internet with remarkable quality and reliability. MPEG-4 AVC technology makes it practical.
Not "One Size Fits All"
It is a misconception to think of AVC as a "one size fits all" technology. The implementation of AVC technology that can facilitate a video conferencing application in a personal computing environment would not be satisfactory to distribute an HD video clip in a broadcast facility.
The good news is the broadcast-quality specifications of H.264/MPEG-4 AVC are now ready for prime time. HD AVC has dramatically enhanced the economics and the practical ability of operators to deliver HD programs along with other bandwidth-intensive services.
There are several compression profiles and levels associated with the AVC standard. Main Profile at Level three ([email protected]) is the appropriate one for the delivery of full resolution 4:2:0 interlaced video, while Level four ([email protected]) is designed for HD applications. At a meeting in Seattle, in July 2004, the MPEG committee approved a number of important High Profile amendments; known as Fidelity Rate Extensions (FRExt). These extensions enhance the scope and value of AVC by offering higher fidelity options, such as 4:2:2 coding and greater sampling range.
Broadcasters need reliable, fail-safe, real-time performance on a 24/7 basis that supports their specific requirements including support for multichannel digital audio, VBI, redundancy, statmux, closed captioning, remote system monitoring, and alarm management. Real-time encoders for broadcast must do more than deliver high quality video at low bit-rates, have low latency (e.g. two seconds), be required to be rigorously standards compliant, and be able to reliably deliver all possible content.
The design goal continues to be to get the best performance using the lowest bit rates. The biggest challenge is to support full resolution processing and all the tools that make AVC efficient; including CABAC, MBAFF, loop filter, and multiple reference frames.
HD AVC compression further presents a substantial technical challenge--demanding at least six and as much as ten times more picture area to process than SD AVC, which itself can consume more than 100 billion operations per second. A real-time platform to compress HD AVC with all the features and tools needs more than six hundred billion operations per second!
There are many companies currently working to implement the H.264/MPEG-4 AVC video standard or claiming to support it. Some vendors are developing silicon solutions for AVC decoding but for encoding there are few off-the-shelf silicon solutions available. Other vendors are attempting to introduce AVC support into legacy MPEG-2 platforms, although the high processing demands of HD present a formidable obstacle.
Hardware & Software
A more effective approach is to combine high quality software coding for advanced algorithm with the most modern, high-performance hardware platforms.
This third option, and the one taken by Modulus Video, is a system based on a strong software foundation that provides the flexibility to evolve the encoding environment, take maximum advantage of increased processing power, and introduce new features.
At Modulus we have demonstrated that AVC can do a substantially better job with many sequences that present a challenge to MPEG-2. Moreover, AVC is at the beginning of its technology lifecycle and will continue to improve significantly over time. As server performance increases, the algorithms will be further developed to drive bit rates lower. Already the first constant bit rate AVC services will be deployed at around 1.5Mbps for SD and between 6 and 8 Mbps for HD.
AVC has emerged as the new open standard with the attributes of efficiency and practicality that most operators agree will ultimately replace MPEG-2 for the delivery of video. Practical AVC solutions are now available to deliver the new standard over existing MPEG-2 transport infrastructures and are now being deployed. HD solutions are following quickly, with the first prototype products from Modulus Video to be demonstrated at NAB 2005.
Don't Count MPEG-2 Out
Many, including Jim DeFilippis, Senior Vice President of Television Engineering, Fox Technology Group, anticipate a 10-15% increase in MPEG-2 efficiency within three years.
Envivio (NAB Booth SL3310)
Complete IPTV System for Live TV, VOD & VoIP
As a leading technology provider of MPEG-4 systems, Envivio, Inc. is well suited to assist operators around the world as they introduce IPTV services. By embedding information within the MPEG-4 stream and treating applications as content, a single client device can decode the video, audio, and data as well as navigate through interactive menus. Using Envivio systems makes new revenue streams and business models possible, because the client device can reside on different platforms such as personal computers, set-top boxes, and mobile phones.
Harmonic (NAB Booth SU10707)
SD & HD Solutions
Harmonic leads next generation video compression technology today with a commercially deployed, powerful standard definition compression platform that supports MPEG-2, MPEG-4 AVC/H.264 and SMPTE VC-1. The company is now pushing the high definition performance envelope with a complete, feature-rich HD solution featuring the highest quality MPEG-2 HD encoder on the market. In support of emerging HD applications delivered over bandwidth-sensitive networks, Harmonic will demonstrate an MPEG-4 based solution.
Additional technology demonstrations will include Harmonic's digital program insertion, which allows operators to regionalize content and increase revenue potential. The complete solution allows for both long and short form content, such as feature-length programs and advertisements, to be inserted into an already encoded video stream. Harmonic will also be demonstrating a new storage encoding system designed to preserve video quality while highly compressing advertisements for digital program insertion and full-length programs for video-on-demand.
Modulus Video (NAB Booth C11416)
This is clearly the year in which MPEG-4 AVC is becoming widely available. While other technologies like Microsoft's WM9/VC-1 video formats are being tentatively considered by some, the majority of the media industry, both in the U.S. and in Europe, trusts the value of MPEG-4 AVC and is making plans to deploy it in the near future. Further proving the universal appeal of AVC, consumer delivery formats such as blu-ray, HD DVD and the latest version (7.0) of Apple's QuickTime, have all embraced MPEG-4 AVC as the best choice for secure content distribution.
It's also quite apparent that compatibility with ubiquitous, legacy MPEG-2 transport platforms will facilitate the introduction of MPEG-4 AVC HD and access to the benefits that the format provides.
At NAB 2005, the company--whose team members have been delivering compression technology for the last 15 years--is eager to prove how its hard work and determination have led to industry leading SD and HD encoding platforms that will help new business models emerge and prosper.
TANDBERG Television (NAB Booth SU7858)
MPEG-4 AVC & Windows Media 9 HD Encoders
TANDBERG Television will show its first-to-market video compression systems for multi-channel, cross platform SD and HD television, alongside its newly integrated N2 On-Demand Solutions.
Debuting at NAB will be the HD ICE platform for advanced compression, EN5990 MPEG-4 AVC and EN5980 Windows Media 9 HD encoders
The TANDBERG Television booth will feature a number of market specific zones, each with live demos of the latest digital video systems from live content acquisition to delivery to the home. Highlights will include end-to-end demonstrations of Windows Media 9 series and MPEG-4 part 10 (H.264/AVC) in live TV over DSL and HDTV DTH satellite delivery networks. These will show the complete TANDBERG Television advanced encoding environment with first-to-market encoding, modulation, statistical multiplexing and control and monitoring solutions. Both of these SD and HD advanced compression demos will show advanced end-to-end systems and interoperability with a wide range of silicon, set-top box, middleware and conditional access providers.