Back-end systems often come in two forms: one is the monitoring and management platform (CMS), and the other is the network video recorder (NVR). CMS tends to focus on networking features, high-capacity forwarding, storage and user management. It is a relatively high-level part, and the closest relationship with the HD camera business should be NVR. Mainly NVR.

Backend concerns

NVR is also the product of network surveillance. Before HD surveillance, NVR appeared as the DVR terminator image, then in the high-definition surveillance system, NVR will be a new force and act as the protagonist of this market. The selection of NVR in the HD surveillance system should focus on the following aspects:

1. Image storage

High-definition monitoring will increase the storage space of video recording, so there must be enough storage space for video storage. In certain professional occasions, the storage requirements are even higher. NVR needs to have enough storage space itself, and can be easily expanded when it needs to be expanded. At present, common storage expansion devices include eSATA arrays and IPsan arrays, and this is often an important indicator to measure the scalability of an NVR.

On the other hand, professional occasions have high requirements for the security of video recording, and the reliability of storage media will become more important. Generally speaking, there are two ways to improve storage security in the industry. One is the disk rotation. Among multiple disks, only one disk works at a time, and the hard disk that is not working is in sleep state, which indirectly improves the use of disks. Lifespan; The second is the use of RAID technology, commonly used in storage arrays. For occasional disk failures, image data can be easily restored after disk replacement. Generally speaking, these two characteristics are also the distinguishing marks of commercial-grade and professional-grade systems.

2. Solutions to common problems

Image local decoding display is the basic feature of NVR products. Due to the need for high-definition image resolution, the NVR is generally required to be able to decode and restore images from high-definition cameras. If the camera is 1920 * 1080, then the NVR must at least support the display of 1920 * 1080 images. The decoding of high-definition images requires huge resources. If 16 channels of high-definition images are connected to the NVR, it is impossible to simultaneously decode and display 16 channels of high-definition images at the same time. High-definition decoding display, multi-picture decoding lower resolution images.

The device generally requires a VGA interface for local decoding and display, which can be connected to a high-priced VGA monitor, and should also have a high-definition interface such as HDMI to adapt to more professional applications.

3. ANR function

The positioning of the application market for high-definition monitoring determines the quality requirements of users for various aspects of the monitoring system. A good NVR device should take into account the possibility of eliminating the risk of image loss caused by possible network failures, and it should also be easy for users to understand and use . At this time, ANR technology is a very good solution. Both high-definition network cameras and high-definition NVRs are required to have this technical capability and coordinated storage, which will not waste storage resources and will not cause loss of images during the failure due to network failure.

4. Access platform to build large-scale applications

From the current point of view, most of the high-definition monitoring systems are still the majority of the industry's private network applications, and the viewing of high-definition images is not limited to local, but should be able to be applied in all aspects of the industry. Therefore, it has become an inevitable demand for NVR and HD network cameras to be connected to a large-scale video monitoring and management platform. In this way, a small group of dumbbell structures composed of high-definition network cameras and a platform can form a huge application network through the interconnection of the platforms. In high-definition systems, whether the back-end has the ability to form a large network has become an important criterion.

Solutions to common problems

HD network cameras have made a qualitative leap in image clarity, but also brought a series of practical problems to the HD surveillance system:

Network bandwidth is tight: The larger the resolution and the higher the resolution, the higher the bit rate during data transmission, which increases the pressure on the network bandwidth.

Large storage space: Double the data traffic, increase the recording capacity, and put pressure on network storage.
The requirements for central control, management software and hardware performance have grown exponentially;
The workload for the management and subsequent analysis of recorded video images will also increase exponentially;

The investment cost is high.