What is the mystery in high-definition network cameras?

Since the development of the security industry for many years, it can be said that it has formed a scale, with integrated movement, high-definition network NVR, and high-definition network module. This time we will talk about the mystery of high-definition network cameras! 1. Surveillance camera control In order to maximize the observation range of the surveillance camera, the surveillance camera must be able to rotate. The method is to use a pan-tilt to install and fix the surveillance camera for rotation. In addition, it must be able to achieve electric zoom and zoom. This requires that the camera in the surveillance camera can quickly and accurately achieve automatic zoom. This has also become a criterion for judging the quality of surveillance cameras. Elaborate on the mystery of high-definition network cameras 2. Surveillance camera lens Focal length: The focal length of a surveillance camera refers to the distance between the lens and the photosensitive element. The magnification of the lens is approximately equal to the ratio of the focal length to the object distance. In other words, as the focal length of the surveillance camera increases and the magnification increases, the close-up view can be zoomed out, and the distant view details can be clearer, and vice versa. Classification: Surveillance cameras can be classified according to the size or aperture of the lens, and different types of surveillance cameras can be selected according to the needs when purchasing. 3. The nature of surveillance cameras a. Definition: The sharpness of the surveillance camera is represented by lines, which are divided into horizontal and vertical lines. The more lines, the higher the sharpness, and the clearer the image. b. Resolution: The resolution used by the surveillance camera refers to the number of dots displayed in the horizontal and vertical directions of the screen. The higher the resolution of the surveillance camera, the clearer the captured image. c. Backlight compensation: When the camera is shooting in a backlight environment, a black image will appear on the screen. This is a disadvantage that cannot exist for surveillance cameras that work 24 hours a day, and backlight compensation is required at this time. When the backlight compensation function is provided, if the camera detects that the video level in an area of ​​the captured image is relatively low, it will increase the amplitude of the output video signal to make the image clear. d. White balance: White balance is an indicator that describes the accuracy of the white color after the red, green, and blue primary colors are mixed and generated in the display. By adjusting the white balance of the camera in the surveillance camera, the color quality of the picture can be improved. e. Signal-to-noise ratio: refers to the ratio of the signal electric frequency to the clutter electric frequency in the surveillance camera, which is often expressed by DB. The higher the signal-to-noise ratio, the better the surveillance camera, and the better the image signal, that is, the clearer the image. 4. Image transmission of surveillance cameras The most widely used transmission method is to realize transmission through the collaborative work of analog cameras, digital hard disk recorders and computer network systems. 5. Sensitivity; If you want to improve the clarity of the images collected by the surveillance camera, you must increase the sensitivity of the camera in the camera. The photosensitive element of the CCD is 3 to 10 times that of the CMOS, so it can be better photosensitive, obtain the optical signal, and then convert it into an electrical signal. Finally, after processing, it becomes a video signal for output or storage.