Building a complete Surveillance System
Like eyes can’t be complete without brain, the cameras can’t be considered as a complete surveillance system without the Network Video Recorder (NVR). Why is that? Every video surveillance system needs to have two main blocks: video capturing and video recording. No matter how intelligent the camera is, there is one task the camera cannot fulfill alone – the video recording and storage management.
There are cameras with built-in SD card based storages, but this capacity can last for several hours at most. Furthermore, any video evidence that is stored directly at the potential crime scene may be at risk of being removed. If that happens, all your efforts and investments into security system will not achieve the desired result. A serious surveillance system needs a centralized service that can store the video streams from all the cameras onto a large capacity disk system further away from the cameras and keep it there for several weeks as the video evidence for future reference.
The main functions of ACTi software NVR
In addition to recording and storage management, the ACTi software NVR contains the interface for live preview, video clip search and playback, video export to AVI format for evidence delivery, camera management, e-map for camera positioning and much more.
Those who are familiar with previous NVR version will enjoy the changes that NVR 2.2 SP3 brings.
The new NVR software comes with the major changes in flexibility & scalability:
• Supports advanced networking architecture, such as NVR remote client over NAT-routers
• Supports large storage space
• Supports Dual Stream from TCM-series cameras and TCD-series encoders
• Supports Windows 7 Professional
• Supports 64-bit Windows operating systems
• Supports HTTP protocol for streaming
• Hundreds of enhancements
• Stable and reliable performance
Why is Dual Stream so powerful?
There are two factors that influence the overall cost of the security solution – the bandwidth cost for remote live preview and storage cost. The camera with H.264 compression can help to save the storage about 30% compared to MPEG-4, which in large scale projects can mean thousands of dollars of saved money on bandwidth and storage. Therefore more and more cameras in the market come with H.264 compression support.
However, most of those cameras have not been designed from the overall solution point of view. While the cameras are streaming H.264 for both recording and live preview purposes, all the NVR servers in the market today are having difficulties to decode 64 channel live preview filled with H.264 cameras. The reason is that although H.264 is a superior cost saver, it requires more computing power on server side.
The ideal solution is Dual Stream – the camera can send out two streams, one with the maximum resolution and quality using H.264 that will be directly stored on the server side without requiring much CPU power, and another stream with MJPEG in VGA resolution for example as a source for live preview. The good quality of the stored video is highly important – should any details be missed during live preview, they can easily be found during high quality playback.
As a result, the 64-channel preview is working smoothly and all the high quality video is stored on hard disk for future playback. The remote live preview bandwidth consumption is very small and the storage space is used economically, too.
