The necessity of Surveillance Cameras
We now have the older generation CCTV cameras and modern IP cameras to pick from. Traditional cameras generate analogue signals to represent video images whereas IP cameras use computer binary methods. IP means Internet Protocol; it means the present day video surveillance cameras are designed to work alongside the Internet. CCTV is short for closed circuit television; it is actually a category that should encompass both older analogues as well as the newer IP cameras but people often say CCTV to mean analogue cameras. The transition is abrupt with regards to technologies employed but very gradual in terms of deployment through the market. We estimate that more than 80% of video surveillance systems set up in New Zealand during 2010 are based on analogue cameras. The penetration will be slightly higher in Western Europe and East Asia, and approximately the same in other OECD countries.
Put an analogue camera along with an IP camera side by side to the moment. Assume they have the same shape and color and we will see that IP is clearly bigger than its analogue counterpart. This is because IP needs extra space to support the computing chips that convert analogue signals to IP. Are these computing chips justifiable for the increase in size, complexity and presumably price? Without starting technical details, the basic answer is that IP technologies have improved the resolution or clarity of video images significantly over analogue. The best commercial off-the-shelf (COTS) analogue camera features a resolution below the VGA equivalence whereas an excellent however, not the ideal IP camera is SXGA. VGA features a resolution of 640 pixels x 480 pixels. SXGA has a resolution of 1280 x 1024. SXGA has 4 times of information density of VGA. If we multiple the 2 dimensions of SXGA, we obtain roughly 1.3 million. We utilize the term megapixels to denote SXGA.
IP cameras have intelligence to enhance the clarity of video images on the top of the resolutions stated earlier. If we go on a picture shot of any friend standing in the door of your house along with his face exploring the camera inside the house, we know that his face is going to be quite dark in the event the outside is incredibly bright. We can adjust the camera so the face has more brightness. At that time, the surface can become too bright to get illegible on the picture. Once we use a good quality Camera giam sat, it would perform some brightness adjustments so the face, the entire body, the inside along with the outside have a reduced range of contrast and all sorts of objects in the picture will be clear and legible. Similarly, the colors of objects might be adjusted under different lighting conditions in order that the display will be as near to reality as you possibly can.