Sharing video has become a viral phenomenon. In January, a now infamous video was posted to the Internet showing a woman walking into a fountain at a shopping mall while texting. In our highly connected and tech savvy world, videos are e-mailable, exportable, and easy to post online for close friends or the entire globe to enjoy. Being able to enact strict policy management rules is becoming a requirement to protect a brand and company's reputation. Well-designed VMS solutions enable end-users to limit access to certain areas of video or to certain functions of the system. Whether it's limited views or restricted access to sensitive areas of a facility, these VMS rules can help thwart rogue Internet postings or other uses outside of the security system.
Take the example of one hospital security director who received a call from a board member who saw surveillance footage of an incident between a doctor and nurse posted on the Internet. The security director was able to narrow it down to five possible members of the security staff who would have been able to access and export the video clip; but that "after the fact" conclusion did not help the hospital avoid the embarrassment and possible liability.
Standardizing on H.264
It is clear that H.264 is becoming the industry's standard compression technology because of its highly efficient methods of transmitting video and maximizing available storage. Its use is fairly widespread in terms of being deployed in VMS solutions aimed at both low- and high-end applications.
H.264 solves many IT complaints that video requires excessive bandwidth to transmit from the camera to the NVR. In part, H.264 is the solution to bandwidth and storage issues that accompany the rise in high-definition, megapixel cameras. The trade-off to H.264's benefits is the additional processing power needed to code and decode the video. This exists both on the camera as well as within the VMS.
Understanding the total number of H.264 video streams that can be displayed concurrently is critical. Newer workstations have more powerful CPUs and higher performance capabilities; however, H.264 performance is greatly impacted by the manufacturer's implementation and video display technology. End-users need to ask questions such as: how many videos can be simultaneously displayed; what is the resolution for each camera, 4 CIF or 1080p; and, what is the fps (frames per second) of each camera.
To drive more H.264 video at higher resolutions and at real-time fps, some VMS designers have taken advantage of an often underutilized resource - the video cards on each PC workstation. The new Microsoft Windows Presentation Foundation (WPF), a graphical system for rendering user interfaces in Windows-based applications, provides a unique opportunity. VMS solutions built on this framework are able to divide the video rendering workload between the PC's CPU and the Graphical Processor Unit (GPU), which powers the video card. Using WPF in a VMS, the intensive video processing - video bit and texture mapping, skeletal frame and image quality - is done on the GPU/video card, leaving the CPU free to decode the video.
VMS systems designed using the WPF architecture can also offer other functionalities such as the ability to have multiple surveillance tabs for mixing live and recorded video, 'Snap and Dock' windows, and more.
While it is important that newer VMS solutions be able to handle the latest in compression technologies, the realities of the market are that most installations are upgrades to existing surveillance systems in various stages of migration to IP, vs. a greenfield installation unencumbered by any legacy technology.
A good VMS should not only be able to flawlessly handle megapixel technology, but also sufficiently and simultaneously leverage other existing codecs - MPEG, MPEG4 - to give users a comprehensive and cohesive view of their surveillance system.
Building with the right parts
No other part of a video management and recording solution takes more abuse than the actual hard drives that physically record the video data. In fact, hard drives are the most common point of failure in a surveillance system. Most VMS solutions are designed to accommodate the hot swapping of hard drives to replace a defective drive or substitute a larger hard disk for additional storage - a feature seen as crucial to enterprise storage requirements.
Most solutions employ SATA drives, known for their speed, storage densities and low cost per gigabyte for near-line storage functions, like archiving and backups. In an average corporate, non-video environment, these drives function well as an 8 a.m. to 5 p.m. solution that can handle documents, images and other items found in the typical business environment. Adding redundancy with additional drives can help alleviate data loss due to a hard drive failure, but it also adds additional costs and complexity to the overall system.