① A megapixel (MP) is a million pixels; the term is 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.
② For example, a camera that makes a 2048×1536 pixel image (3,145,728 finished image pixels) typically uses a few extra rows and columns of sensor elements and is commonly said to have “3.2 megapixels” or “3.4 megapixels”, depending on whether the number reported is the “effective” or the “total” pixel count.
– 5.5MP 2200×2500 = 5,500,000 pixels
– 25MP 5000×5000 = 25,000,000 pixels
(Megapixel Calculator)
http://web.forret.com/tools/megapixel.asp?width=2200&height=2500
