Not long ago VGA and D1 resolution IP cameras were common in the video surveillance market. At that time everybody knew how to evaluate video quality of the camera. With the appearance of 1-Megapixel and 1.3-Megapixel cameras it was still quite easy to compare products with each other. However, now multi Megapixel cameras are being introduced to the market – 2 MP, 3MP, 4MP, 5MP, 10MP, etc. Everybody is confused – how to compare these products with each other? Does a 10-Megapixel camera provide better video quality and more details compared to 4-Megapixel camera? Not necessarily! The higher number of pixels does not guarantee more details or better video quality!
Look at the example below. Two images with different resolution are provided.
With simple visual observation you can tell that the image quality of the left image is much better than the right one. The details of the left image are very clear while the right one looks blur as it was out of focus despite of the fact that the lens was adjusted to the best possible focus in both cases.
If your camera produces images with high pixel count but low clarity like the image to the right, you not only miss all the needed details, but you also waste your bandwidth and storage space with needlessly large number of pixels.
The following chapters explain the factors that influence the video quality. We will also discuss how to test the cameras and decide which ones provide the best video quality.