| With many years of experience, the Home Office | | | | registration plate, or it is sufficient to notice one's |
| has developed a set of requirements on the use | | | | presence. |
| of monitoring systems by the police in various | | | | There are no clear criteria for collecting evidence |
| investigations. To be able to effectively use the | | | | for the court. If the judge rejects the material |
| material obtained through a CCTV system, it | | | | because of insufficient quality, it becomes useless. |
| must meet the requirements set out below, | | | | Therefore a good idea is to check the quality of |
| collected in four sections: | | | | images from the cameras by testing the ability to |
| - Quality | | | | distinguish details in similar conditions in which the |
| - Recording | | | | cameras will operate. |
| - Export | | | | |
| - Playback | | | | City Monitoring Center |
| QUALITY | | | | When testing the quality, it should be noted that |
| An important group of these requirements are | | | | live images usually look better than those played |
| the rules for the selection of the equipment. | | | | back from the recorded material. |
| What image resolution is suitable for a specific | | | | A very important issue for the court is time |
| application? Which kind of compression should be | | | | synchronization of all recorded material. |
| used for transmitting and recording the video? | | | | Another thing that cannot be disregarded is the |
| How many frames per second are to be saved? | | | | capacity of the archives. The storage capacity |
| These questions form the basis for the list of | | | | has to be matched to the image quality and |
| quality guidelines: | | | | archive period. Finally, it is good to remember that |
| - Specify the main requirements - make the list | | | | the quality of the material also depends on the |
| of objects/areas to be monitored with the | | | | maintenance of the system. It includes regular |
| relevant resolutions and choose the equipment | | | | focusing of the cameras, cleaning lens and |
| that meets these requirements | | | | housings etc. |
| - Specify requirements for recording - it is | | | | Modern city video surveillance systems are |
| recommended to watch or print still images | | | | equipped with day/night, fixed, PTZ, and |
| recorded by the prospect DVR to find out | | | | megapixel cameras. The main parameters include |
| whether it provides satisfactory results | | | | angle of view (depending on the lens), sensitivity |
| - Use technical means for time synchronization of | | | | correlated with the ability to work at low light |
| all components of the system | | | | conditions (depending mainly on the image sensor), |
| - Adjust the storage capacity to the image quality | | | | video resolution, and frame rate (the number of |
| and archive period, and never vice versa | | | | frames transmitted per second). It should be |
| - Regularly maintain all equipment | | | | noted that PTZ cameras should ensure higher |
| Before ordering and installing CCTV system the | | | | frame rates, because it has an impact on the |
| user should know what is to be observed and | | | | accuracy of camera control. In addition, the optical |
| how precisely. For example, whether the system | | | | zoom can help to capture interesting details. |
| should allow to recognize the face of a person | | | | Unfortunately, PTZ control can be effectively |
| passing through an entrance or read a car | | | | performed only by the operator. |