Quality corresponds to some of the objectives of video surveillance, which are: to identify an unknown person, to recognize a known person, to observe a human action, to detect a human presence, etc. The usual criteria for identification, recognition, observation and detection are established according to the number of points (pixels) available to represent a human face. The usual criteria for identification, recognition, observation and detection are established according to the number of points (pixels) available to represent a human face, and there are also criteria for the legibility of a vehicle license plate.60 pixels are needed for identification to represent the width of a face that measures on average 15 cm (and 90 pixels for the height of the face, i.e. about 22.5 cm).

Horizontal resolution for the usual quality criteria:- Identification: 60 pixels for 15 cm or 400 pixels/m
– Recognition: 30 pixels for 15 cm or 200 pixels/m
– Observation: 9 pixels for 15 cm, i.e. 60 pixels/m
– Detection: 4.5 pixels per 15 cm or 30 pixels/m- Human eye plate reading: 60 pixels per 50 cm or 120 pixels/m- Human eye plate reading: 60 pixels per 50 cm or 120 pixels/m
– Automatic plate reading (ANPR): from 75 to 100 pixels for 50 cm, i.e. 150 to 200 pixels/m

● You now want to know how far you will be able to identify a person if you pass the 5 M pixel resolution. Simply replace the value 1920 by the new horizontal resolution, i.e. 2592 and you will get a distance of 2.14 m.
● You now want to know, with the same settings, how far you will be able to recognize a person. You then have to change the quality from 400 to 200 pixels/m. This will give a distance of 4.29 m.
● A 5 m wide gate is 50 m away from the point where you can attach a camera. To determine the corresponding angle, click on the angle pencil (which becomes a calculator) and enter the two values: “distance in m” 50 and “width in m” 5. The resulting angle is 5.7°.
Then determine the camera resolution you will need to identify a person.
Without changing the parameters, distance, width and angle, click on the pencil of the horizontal resolution of the camera (which becomes a calculator). Enter 400 for the quality in pixels/m. You get 2000 pixels of horizontal resolution.
● Up to what distance can you perform recognition with a 4k CCTN8EW01 camera?
Click on the “Distance in m” pencil (which becomes a calculator). Enter the known values, i.e. the horizontal resolution of the camera which is 3840, the quality in pixels 200 (note that this determines the “Width in m”), and the minimum horizontal angle of the camera: 46°. The resulting distance is 22.62 m and the width of the field you can monitor is 19.20 m.