Bandwidth boom aids AV

As AV systems continue to migrate onto IT networks, InAVate examines the technologies that are making this possible.

Originally intended as data communication systems for computer networks, in-house LANs within commercial enterprises have existed for years. However they have become more and more clogged-up as new services, such as voice, audio and video applications have been added to them, resulting in the need for higher and higher bandwidth networks to be installed.

It is now becoming possible, with the advent of Gigabit and fibre networks, to use a single common carrier for virtually all communication requirements; so all data, telephony, environmental control videoconferencing and lately, audiovisual distribution can be routed and supplied around a building or site.

What this means in practice is that the expansion of the data ‘roadway’ has, in turn, created further opportunities and a greater desire to develop sophisticated applications which have started to be introduced over the past two or three years. A major beneficiary of this expansion in speed and bandwidth is the AV distribution market. It is now possible to encode real time audio and video into IP packets for distribution such that they can be decoded back to a viewable format without any delay in the process that could cause jitter, freezing or degradation of the image itself.

We are all now very familiar with the Windows Media and Real Video Players and are aware of the quality issues associated with them. These are largely brought about by the need to heavily compress video down to a few hundred Kbytes per second for distribution over the Internet. Without such a bandwidth limitation it is actually possible to encode and packetise video at a lower compression rate (to 2-3 Mbps) and distribute it over a LAN – at rates and quality levels comparable to digital TV and even DVD image quality. The equipment required to perform this function is becoming available and making the process economically viable for organisations outside mainstream broadcast operators. At the receiving end, the distributed content can be viewed on standard PCs with the appropriate decoding software, but more appropriately on dedicated set-top boxes and receivers that don’t rely on complete PC configurations; rather using embedded software and operating systems including Windows CE and Linux for dedicated applications.

Which opens up massive new markets for AV distribution over IP networks: within businesses, hospitals, hotels and entertainment facilities, even down to high end domestic installations.

To provide encoding technology, many traditional broadcast equipment suppliers are lowering the complexity of their entry-level equipment to meet this demand. Companies such as Optibase, Tandberg TV and Grass Valley, who for years have produced very expensive, ultra-robust equipment for broadcast studios are turning their attention to the commercial marketplace to satisfy this demand, aiming at the higher end of the market within blue-chip and FTSE 100 companies, rather than the lower end, smaller organisations and special applications like hotels and cruise ships.

Lower down the scale and perhaps of more interest to a greater number of users are new, specialist, video processing companies creating dedicated encoding equipment and switching routers that are aimed at this level. MediaPOINTE, a company based in California produce a range of IP-based digital video distribution components that form complete AV over IP solutions for education, healthcare, public network and enterprise applications; including distance learning, video conferencing and video sales presentations. The system is based around the DNS150 family of low-latency Digital Network Streamers which accept most forms of video signal, including composite, S-video and SDI to produce an MPEG compressed stream between 800K bps and 15 Mbps on a 10/100 base-T Ethernet connection. Full screen NTSC and PAL video is accommodated throughout the system, resulting in high quality real time TV pictures. Marketed as a company that provides “everything AV over IP”, a range of ancillary video products is also available. These include devices to capture and print video stills within the system to a hard drive, flash memory stick or network printer and are useful in producing hard or soft copies of meetings, video conference sessions and presentations. Network storage and video recording devices allow video and PC content to be streamed onto a network with simultaneous storage for archiving or further transmission. Colin Sturtevant, VP Sales for MediaPOINTE commented: “Exciting new applications are driving the migration to IP at a rate faster than first expected. And the market is demanding that these AV over IP products seamlessly handle high resolution data, audio and video transmission, from any source to any recipient within their network, regional or global.”

Exterity, a UK company, produces the idaptor DVB-IP Gateway family of DVB streaming equipment that capture broadcast television and convert it to IP streams for transmission over a building network. A single 1U rack unit is capable of receiving and processing all UK Freeview channels to remote set-top boxes or PCs. Similar products convert standard video to compressed MPEG-2 at up to 14 Mbps for onward transmission, although the company claims that 4-6 Mbps is adequate for the majority of applications and is sufficient to provide full screen, full rate video at standard definition TV levels. Colin Farquhar, Exterity's CEO explains the company's philosophy and activities to break into the market: "It's taken several years working with IT management in enterprises to get to a position where we have proven that video distribution is possible alongside the normal date and VoIP streams without adversely affecting them. We are now able to deliver hundreds of channels to thousands of users on a corporate LAN and this is driving the market very effectively".

Adtec Inc, have been producing MPEG storage and playout devices as digital VCRs for several years aimed at retail and other environments that required high quality video replay. Some time ago the company incorporated IP playout into some of their products, to produce a line of MPEG digital video players as network appliances, which took them into the corporate marketplace. Further product additions have produced a complete set of products that will insert video and DVB streams onto IP networks and include the DTA Digital Turn Around Media Routers with integrated QPSK, QAM, and ATSC tuners and conditional access for enterprise and DTH applications utilizing low-cost IP set tops. With sales in excess of 200,000 units worldwide, Adtec have proven that the market for high quality MPEG based video servers is large and that IP related product demand is set to expand accordingly. Closely coupled with Adtec, and distributed in the UK by the same company, Techex, is another pioneer of AV over IP distribution, claiming to have released the first MPEG Video Network Appliance in 1998, VBrick has focused considerable resources on developing asset management software to search and launch video material on network servers as well as scheduling software for live and stored content from VBbrick encoders. The EtherneTV Portal Server software seamlessly controls the filing, access and usage of media assets as well as providing communication with users on the system at any time. Joe Chordas, Channel Sales Director, “We have grown over the years to meet the needs of systems integrators in the core markets of Government, Education and Corporate and it was essential to offer a mechanism that gave transparent control of the capture, storage and delivery equipment. A teacher in a school doesn’t need or want to know how the system operates, but just wants to use it”. A recent Frost & Sullivan market survey recognised that Vbrick has secured over 40% of the worldwide market and gave the company its award for Market Leadership, commenting that “VBrick’s flexible technology and attractive price is a catalyst for organizations to rapidly adopt digital video communication to wireless devices, the desktop, or Internet for enhanced clarity and productivity.”

The evolution of video compression and distribution from MPEG-2 to MPEG-4 in applications outside satellite and terrestrial TV transmission has provided huge savings in bandwidth. MPEG-2 was first developed over a decade ago, and utilised technology of the day. Unfortunately the technique was fixed and the compression algorithms were not readily modifiable to provide better compression rates, although faster and faster processing enabled more efficient encoding so that single-pass real time conversion became possible which was crucial to the distribution of live video over IP. MPEG-4 is a new flavour of compression using different algorithms and is able to deliver better quality images at the same sort of rates; which is why it is the standard adopted for Sky’s HD transmissions using new set-top boxes. For office-based AV systems the adoption of MPEG-4 reduces the bandwidth requirement of the network to levels that are even more acceptable to IT managers.

At the receiver end, Amino, based in Cambridge is the recognised global leader in IPTV set-top boxes with deployments in over 50 countries around the world. Mike Leigh, Amino VP Sales & Marketing ( Modelo) is responsible for hospitality solutions and has delivered over 70,000 units into hotels for in-room pay TV systems: “We supply some of the largest hotel entertainment suppliers including names like On Command, GuestTek, Total Vision and NEC who installed 16,000 STBs in Travelodge rooms. The trend at the moment is for convergent services. Hotels are being built, or refurbished, to take advantage of combined services delivered to rooms over a single Cat5 or 6 cable. They are using standard well-proven data switches from big-name companies like Cisco, rather than running a separate coax cable, which is far more awkward to install and using intricate analogue video switching”.

Amino’s STBs are capable of receiving and decoding MPEG-4 (H264) streams so later models are already HD compliant, a fact which Mike knows is critical in an industry where providing up-to-date services is essential to the success of a hotel, particularly at the higher end of the ‘star’ scale. “With the advent of HD the hospitality industry is reaching a pivot point with a degree of uncertainty: the hotels are replacing old CRT TVs with flat screen HD-Ready devices and rewiring with Cat5/6 cable to replace coax that cannot cope with HD bandwidth. Service providers are upgrading their systems to deliver HD content and wondering how the business model will work and the studios are trying to determine how to protect their content. Fortunately we have already launched a range of HD compatible receivers, so recent installations are already geared up for high definition pay TV”.

As with many large and potentially complex systems, individual manufacturers generally focus on providing component parts rather than complete systems, with the result that strong partnerships and alliances form and systems integrators are key to delivering solutions. Amino for example, provide just the receiver devices. They have working relationships with Envivio, Harmonic, Optibase and others for encoding, as well as Calix, Occam for switching components and a plethora of other companies for other components. What this means is that whilst devices are designed and proven to operate together it can still be somewhat daunting as a systems integrators to deliver full systems. Peter Hunt, MD of AV consultant Hewshott Associates advises many blue-chip organisations on AV deployment strategies and sees the convergence of AV, videoconferencing, data and voice as an area that needs to be tackled together: ”Many global organisations that we work with recognise that all services should be delivered over a single network within offices and further afield between branches, sometimes across continents. There is still a necessary distinction between the technologies at the presentation end; what you do with the content when it arrives, which requires specialist installers. But it all has to be managed within the IT umbrella and the equipment has to be integrated into one cohesive whole, rather than as piecemeal components or parallel systems”.

It is apparent that with so many advantages over discrete systems, AV distribution on IP is growing rapidly as a viable and dependable solution for a whole range of target markets. It clearly, does not cause data throughput conflict on local area networks within commercial sites. Encoding technology, which was another limiting factor has developed to the point now where single pass encoding is of sufficient quality and speed to deliver more than adequate quality at standard definition level. The indications are that even HD can be delivered as compressed data within the technology as it stands today and this has massive implications on all video systems across the whole spectrum of applications. AV over IP is set to become the next great ‘technology of the future’ within the commercial environment.

Article Categories




Most Viewed