|
«Any IR camera has a fairly long period of time in the evening (1-3 hours), when the backlight is not yet on, and the image quality has deteriorated due to insufficient lighting. What do camera manufacturers say about this, how to deal with this? — Maxim DERGACHEV, Volgograd»
Sergey PIGOREV, Director of the Poliset-SB Group of Companies, answers the reader's question.
The Russian video surveillance market has introduced IR surveillance cameras with a built-in IR controller, which reduces the risk of image quality deterioration due to sudden changes in illumination.
And at the end of last year, video cameras with 3D adaptive Noise Reduction Filter (3DNR) noise reduction technology were introduced.
This technology is used in many devices and is based on successive blending of frames over a certain period of time. In theory, by blending frames over a long period of time, it is possible to completely eliminate noise in the image. This is used in film production to remove noise from the blue or green components of the frame. Successive frames of the same blue or green component of the frame are blended together, which effectively removes the noise found in any individual component.
The essence of the 3D adaptive Noise Reduction Filter technology is the pixel-by-pixel analysis of several frames to determine the optimal processing method for each pixel in the image. As a result of an individual approach to each pixel, we get a more accurate noise reduction mechanism with minor artifacts on moving objects compared to conventional noise reduction.
«Currently, remote video recorders are increasingly monitored from a single center, using specialized software. At the same time, the question arises of protecting the corporate network from viruses that may be in the recorders and attack the network from time to time. How is this problem solved? — N. P. KOROLEV, Moscow»
The reader's question is answered by
Dmitry STRELTSOV, regional manager of Mitsubishi Electric EVS for Russia and the CIS.
It should be noted that there is still no unified classification and naming of viruses. Therefore, it is customary to divide viruses by the objects they affect, by the technologies used by the virus, by the language the virus is written in, by the operating systems and platforms they affect.
In the video surveillance systems market, the well-known distribution of PC-based and Stand Alone recorders implies the use of the Windows operating system in the first case and Linux in the second.
Unlike most other operating systems, Linux does not have a single official configuration. And each developer can essentially create his own operating system, which significantly complicates writing a virus for each of its versions. The GNU/Linux operating system, like UNIX and other Unix-like operating systems, is considered to be protected against computer viruses. However, viruses can potentially damage unprotected Linux systems and affect them, and even possibly spread to other systems. The number of malicious programs, including viruses, Trojans, etc., specifically written for Linux has grown in recent years. For example, in 2005 their number doubled (from 422 to 863). In turn, it is worth noting that the number of viruses written for Windows is several orders of magnitude higher.
The main difference between Linux viruses is that all systems are very different from each other. Any program, including malicious ones, uses some system functions. The creator of the virus counts on the presence of certain libraries, which can number in the dozens. And since each Linux operating system can be original, the resulting virus can actually work on 1-2 machines out of 1000, but even there it will be severely limited in its rights.
But is it possible to reduce the risk of infection of recorders from viruses to zero? Yes, there is.
Choose recorders in which the operating system is recorded not on the hard drive, but on the flash memory built into the motherboard. In this case, all program files are assigned only «for reading».
Thus, the virus physically cannot be brought into the video recorder, and, therefore, cannot harm the system files. Which significantly increases the safety of using video recorders in corporate computer networks.
|
