Smarter systems offer better solutions in video arena

Bandwidth and compression technology are at the forefront as the industry looks to improve the quality of video
Tuesday, June 1, 2004

With network-based digital video surveillance at the heart of many security systems these days, issues related to bandwidth and compression are taking center stage.

Even though networks are becoming faster and growing quicker than before, “bandwidth and network capacity will always be your choke point,” said William L. Stuntz, chief executive officer of BroadWare Technologies. The problem now, Stuntz added, is that users often have to make a trade off between video quality and bandwidth.

Video is taking up bandwidth all the time, said Paul Smith, chief operating officer for DVTel Inc. “It’s not like using a computer on a sporadic basis,” he explained. “The bandwidth has to be large enough to support it (the security system).”

“The more bandwidth we create, the better the quality,” said Yvonne Cager, worldwide manager-DSP video solutions marketing at Texas Instruments. “So the focus has been on improving bandwidth.”

Compression Options

One challenge, noted J.B. Fowler, DSP application engineer for Texas Instruments, is determining which algorithms to use to compress video and maximize bandwidth. The three compression standards starting to be used widely, Fowler said, are WMV9, MPEG4 and H.264.

But other compression codecs are also being mentioned by industry participants, including Motion JPEG, MPEG2, as well as proprietary ones.

“With all the different compression standards,” said Cager, “a lot has to be done to make sure (a system) can support multiple codecs platforms.” And, she said, people are exploring which codecs work best for their needs.

One system can need many types of compression, agreed Stuntz.

Kristi Konotchick, director of business development for Inetcam, said for companies that already have equipment in place, “network cameras place a huge strain on the network.” But such a challenge, she added, presents opportunity for companies such as Inetcam, which developed proprietary compression software.

American Dynamics also has its own compression standard, known as ACC, said Gene Hammond, vice president and general manager. “We’re using proprietary variances to get even greater compression,” he explained.

TI’s Fowler said software has become the focus, rather than hardware, because of its inherent flexibility. “There are hardware solutions out there,” he said, “but if standards change, they (customers) have to use all new hardware.”

It all started with digital
Tied in with the discussions on bandwidth and compression are those first fundamental steps of moving to a digital platform.

Ali Eghbal, president of Vigitron, said the transition from analog CCTV systems to digital still presents a challenge for the industry. He said many end users have legacy analog systems, such as those used in casinos, but want to add digital cameras as well.

In that instance, he said, the use of unshielded twisted pair as the transmission mode can ease the transition. “Wiring can be more expensive than the camera itself,” Eghbal said. “So if you want to replace an analog camera with a digital one you can still use the (twisted pair) wire.”

Transmission quality is also a concern among end users. Not only do they want to get effective information out of their video surveillance, they also need high-resolution images for forensic purposes.

As the industry continues to migrate toward IP cameras, Hammond said, advantages will emerge, such as the ability to use existing wiring and cabling and the use of less bandwidth because compression is done at the camera end.

A key advantage of digital technology is the ability to have an intelligent system that will capture effective data.

“When you have that ability you can diminish the amount of traffic on the network,” explained Smith of DVTel. An intelligent system can be accomplished through motion detection or other devices that target what needs to be recorded and when.

A good filtering system, like motion detection, helps, said Eghbal, because you are getting and transmitting only useful data.

The concentration going forward, said Hammond, “will be more on managing and mining the data than it will be on how you capture it in the first place.”

“Certainly we’re seeing more and more emphasis on intelligence in the system,” according to Smith. “One reason is to reduce recording. But it’s also meant to improve the efficiency of the detection and alert humans to watch an event 2 percent of the time, not monitor it 100 percent of the time.”

Video analytics, as Stuntz referred to it, is a great solution for both bandwidth and monitoring issues. “As you put in all those cameras,” he explained, “it becomes more important to shift the burden.”

He said by pushing the intelligence as close to the camera as you can get it, the system grabs and records only the high-resolution video that it needs.

In addition, he said, events can then be sent to secure, remote servers, which is “one more way to manage bandwidth.”

Compression is also aiding storage requirement, said American Dynamics’ Hammond, by lengthening the number of days information can be stored without overreaching capacity.

As bandwidth improves, said TI’s Cager, the likelihood is more storage of relevant data on site.

However, there is more interest in storing data in secure, third-party facilities. “For immediate and quick interaction,” Fowler said, “storage on site is important. But you should also be able to pour stored video off site.”

Another area that is testing the bandwidth capacity is on the wireless side, said Inetcam’s Konotchick. While bandwidth is an issue now, she said, new developments, such as Verizon Wireless’ 1xEVDO, a third-generation, high-speed wireless network, could open up the possibilities. Then the issue is not bandwidth but rather security for remote viewing.

Fowler said he has also seen more interest in wireless cameras which capture, compress and send video over a wireless link to a receiver.

The draw, he said, is “for customers with existing security systems who don’t want to run new cable - that’s the benefit there.”