A megapixel (MP) is 1 million pixels, and is a term used not only for the number of pixels in an image, but also to express the number of image sensor elements of digital cameras or the number of display elements of digital displays. For example, a camera with an array of 2048Ã–1536 sensor elements is commonly said to have '3.1 megapixels' (2048 Ã– 1536 = 3,145,728).
Digital cameras use photosensitive electronics, either charge-coupled device (CCD) or complementary metalâ€"oxideâ€"semiconductor (CMOS) image sensors, consisting of a large number of single sensor elements, each of which records a measured intensity level. In most digital cameras, the sensor array is covered with a patterned color filter mosaic having red, green, and blue regions in the Bayer filter arrangement, so that each sensor element can record the intensity of a single primary color of light. The camera interpolates the color information of neighboring sensor elements, through a process called demosaicing, to create the final image. These sensor elements are often called 'pixels', even though they only record 1 channel (only red, or green, or blue) of the final color image. Thus, two of the three color channels for each sensor must be interpolated and a so-called N-megapixel camera that produces an N-megapixel image provides only one-third of the information that an image of the same size could get from a scanner. Thus, certain color contrasts may look fuzzier than others, depending on the allocation of the primary colors (green has twice as many elements as red or blue in the Bayer arrangement).
BriefCam is attending the ASIS show in Philadelphia with video synopsis technology that enables footage to be shown simultaneously on one screen to detect events which can be shown in detail in one click