Generally speaking, civilian-level surveillance cameras are 420 lines, 480 lines, 520 lines and so on to represent the sharpness of the camera, that is, the number of lines scanned horizontally on the monitor. And the pixels of the merchant's mouths are often exaggerated, so choosing a surveillance camera does not weigh in pixels.
According to the professional explanation, the usual surveillance cameras have only two grades, low-solution 330-line, about 480 lines of high solution. A number of domestic enterprise product labeling 420 line is actually 330 line products. In the past, the 480-line camera was generally called HD cameras. With the improvement of production technology, processing capacity to reach 7MH DSP Qualcomm Filter to make the horizontal resolution to reach 520 lines, so the emergence of further high-definition surveillance cameras products. But in essence, it is only analog surveillance cameras on the existing DSP and manufacturing technology based on a limit upgrade, it will be the traditional 480-line high-definition standards to 520 or 540 lines. Actual camera image sharpness performance, in addition to the use of CCD technical indicators, back-end signal processing technology such as hook circuit, contrast, color reduction, signal-to-noise ratio, selection of lenses, focusing accuracy and so on factors, can affect the image clarity.