With worldwide recession at the forefront, video surveillance users turn to encoders as a cost-effective and efficient migration path to IP. A&S investigates the market potential for video encoders, the differentiating criteria and its applications outside of security. Additionally, the competitive features of video encoders and the reasons why analog cameras set with encoders have leverage over network cameras will also be discussed.
As video surveillance heads toward IP and analog cameras still make up most security applications, video encoders and servers demonstrate a tidy migration path to digital. With the current recession in mind and technological development factors to consider, choosing analog cameras supported with video encoders or servers is becoming a trend.
Both video encoders and servers are devices that convert an analog video signal to a digital video signal over an IP network, such as LAN, Intranet or Internet, said Roni Klein, VP of Sales, Verint Video Solutions, Verint Systems Asia Pacific.
The worldwide market for video encoders used for surveillance was estimated to about US$450 million in 2008, with Europe, Middle East and Africa (EMEA) accounting for the largest portion of sales, said Alastair Hayfield, Market Research Analyst of Security & Fire Group, IMS Research. With the entire IP video market estimated to grow by 10 percent in 2009 and video encoders forecasted to grow by a respective 10 to 20 percent within the overall IP growth, manufacturers have honed in on certain distinguishing features of video encoders to compete in the market, said Joel Rotem, Senior Marketing Director of Mango DSP. Included in these features are compression formats, scalability (including number of channels), preprocessing features and storage capabilities. Key international players for video encoders include Axis Communications, Bosch Security Systems, Optelecom-NKF, Verint Systems, Sony, ioimage, Mango DSP, TeleEye, and Chinese companies such as Hikvision and Fibridge.
Rising Compression Standards
Currently compression formats used in encoders for video surveillance applications include M-JPEG, MPEG-2, MPEG-4, H.264 and proprietary compression formats, with MPEG-4 being the most widely used.
M-JPEG compression formats compress each frame on a frame-by-frame basis, said Robert Beachler, VP of Marketing, Stretch. MPEG-4 provides better compression capabilities because it looks at the previous frame of video and only compresses the things that have changed from one frame to another, as opposed to compressing each frame individually. This means that users can store more video with less disk space.
Comparing MPEG -2, MPEG -4 and H.264
While MPEG- 4 is the most common compression format for video surveillance, H.264 is gaining momentum, said Steven Zhang, President and CEO of Fibridge.
"H.264 is a joined development between ITU-T Video Coding Experts Group (VCEG) and ISO/ IEC Motion Picture Experts Group, resulting in the best possible picture quality at the lowest bit rate," said Nafis Jasmani, Regional Sales Manager ASEAN of Axis Communications. In comparison to MPEG-4, H.264 retains MPEG-4's video quality but is three times more efficient in streaming and uses about half the storage space of MPEG-4, resulting in a 50 percent reduction of storage costs, said Beachler.
However, one reason users today still prefer MPEG-4 is that MPEG-4 is a matured compression format and many developers of network video related software currently support it. The software developed is integrated with features of the encoder, said Jasmani. In contrast, H.264 is still in its infant stages and many software developers are still working on its integration features.
"As compression algorithms can be implemented in very different ways, the standard itself does not imply quality. All H.264 is not created equally; variability exists in bit rate, video quality, resolution and the encoding profile," said Ruud Toonders, Product Marketing Manager IP Network Video EMEA, Bosch Security Systems.
An overly simple H.264 implementation may produce worse results than a proper MPEG-4 implementation, Klein cautioned. The technological struggle for H.264 lies between improving video quality image and sacrificing as little computing power as possible. As computing power increases, MPEG-2 and MPEG-4 will be replaced by H.264.
The cost and availability of H.264 equipment has made the market slow to accept the new compression standard, which was more expensive than MPEG-4. "Now however, due to the innovation of semiconductors, the price per channel has lowered considerably, to a point where most video encoder companies are developing products that use H.264," Beachler said. "While these companies may still support legacy standards, most today are now geared towards H.264, and rising demands of customers will continue to spur the market."
Bandwidth is an expensive resource, and requires better compression to utilize network resources more efficiently. Some video encoder manufacturers develop proprietary compression technologies, catering to different bandwidths to optimize video transmission and recording. TeleEye specializes in a compression format that can achieve 50 percent faster refreshing frame rate compared to MPEG-4 in transmitting video through broadband Internet connections, said Dr. Wallace Ma, CMO, TeleEye. For storage purposes, its compression format can save up to 40 percent compared to MPEG-4, on the same hard drive capacity.
With video encoders, flexible platforms differentiate between needs of large-scale applications and small-to-medium businesses. For less demanding applications, such as small-to-medium businesses, users may not require running multiple encoders on a single platform simultaneously. For larger applications, some vendors take one video input and use two or more compression algorithms to convert analog signals to digital, known as "dual streaming."
As today's video surveillance installations serve multiple applications of viewing, storage and remote client access, every compression algorithm has been developed for specific applications. H.264 is efficient for storage, while M-JPEG is suited for Web applications and MPEG-2 is suited for high quality, low latency viewing. "By providing an encoder platform simultaneously capable of supporting all three compression formats, system integrators can then match each with its intended application," said Roger Decker, Product Marketing Director, Optelecom-NKF. "Users can optimize their systems using multiple compression formats."
Dual streaming allows a video input to be encoded with different parameters, for a live-view stream and a recording stream with different frame rate and resolution settings, Klein said. Video can be viewed and analyzed at high resolution for superior clarity and analytic accuracy while recorded at a lower frame rate. This reduces data transport and storage requirements.
As video encoders will be used in hybrid environments, scalability is an essential feature of differentiation. To be expandable, encoders should be able to accommodate several channels.
"Some encoders are designed in one box (with channels of 8, 16 or 32), whereas others, based on modular systems, can support more channels as the port's requirement increases," said Jasmani. Currently there are single channel encoders (1-1 ratio of camera and encoder) or multichannel encoders, like Axis's encoders, that can support up to 84 channels, with redundant power supplies and network connections. Multichannel encoders can convert analog signals to digital for larger systems, where all existing cameras are connected via coaxial cables to the encoder. Large hybrid projects, including airports or railway systems with up to 3,000 cameras, can choose multichannel encoders for the solution's modularity, allowing users to connect their analog cameras to a Wide Area Network, said Gerard Otterspeer, Product Marketing Manager CCTV IP EMEA, Bosch Security Systems. Modular systems can be expanded by integrating encoders into standard 19-inch central server racks.
Placing a different spin on multichannel encoders, users can choose encoder boxes that are essentially empty cases with available slots, insert encoders in the casing and digitize cameras six at a time. "When all slots are occupied, you can make the necessary port adjustments, with minimum disruption, making it cost effective for migration to IP," continued Jasmani. As an example, a 250-camera project of 20 analog cameras may connect the 20 analog cameras to an encoder box and use four six-channel video blades to support 24 analog channels, rather than choosing in-built redundant multichannel boxed solutions.
Aside from flexible compression platforms and scalability, storage features receive a great deal of attention for video encoders. Because network connections may break down, memory cards are offered as a supplementary mode of storage, which can be attached directly to video encoders. These flash memory cards are used as local storage for redundancy purposes to prevent single points-of-failure that arise during streaming, said Jasmani.
Other options to record at the encoder level include recording via Internet Small Computer System Interface (iSCSI) disk arrays, where features and functionalities are similar to the embedded hard disk or memory card, but video footage can be scaled horizontally and shared over multiple disk arrays, Otterspeer said. iSCSI establishes and manages connections between IP-based storage devices, hosts and clients, using the Internet protocol for video recording and storage.
As security converges more and more into the IT world with IP networks such as LAN, Intranet, or Internet, many users are experts in safety and security, but are not familiar with its IT aspect, Klein said. For encoders, there are compatibility issues for third-party software and hardware. A great deal of digital information proceeds from the camera to the video management software, involving storage, streaming to remote surveillance, and other functions. Incompatibilities between existing video management systems from one vendor and video encoders from another could pose problems that are time consuming and require maintenance, Klein said. To overcome incompatibility issues, encoder vendors need to consider all relevant components of an existing system prior to installation.
Video encoders in security are expected to eventually be replaced by network cameras. However there is a range of ancillary applications for encoders that use installations and technologies similar to surveillance. These include remote monitoring, guidance and meeting, as well as broadcast, video conferencing, and video phones. The broadcast industry has used encoders in differing forms to stream broadcast TV across a network, Beachler said.
Encoders have also been used in machine vision applications, industrial control and military applications, including robotics and UAVs, where form factors and interfaces may differ but the encoding and streaming of video is used in a similar way, Rotem said.
Even for medical purposes, video encoders can be used to stream video sent from an ambulance to the serving hospital, speeding up processes and efficiency, said Daniel Doron, Marketing Manager of ioimage. Clearly, the applications for encoders stretch far and wide, not being limited to the realm of security.
Paving the Way
"The video encoder market will be strong and dynamic in the years to come," said Junke Chen, Project Manager, Hikvision. The current industry is slowly but surely moving toward total IP solutions. Several vendors agreed that as network cameras are developing and becoming less expensive, they will replace video encoders.
However, it is important to remember that security remains a conservative business. With the economic recession, previous predictions are wavering and the way ahead is characterized by users with a marked preference for proven technologies. It is therefore prudent and strategic for video surveillance providers to take heed of the analog encoder landscape and offer clients flexibility when designing solutions.