In [[imaging science]], '''imageImage processingProcessing''' is processing of images using mathematical operations by using any form of [[signal processing]] for which the input is an image, a series of images, or a video, such as a [[photograph]] or [[video frame]]; the output of image processing may be either an image or a set of characteristics or [[parameter]]s related to the image.<ref name="GonzalezWoods2008">{{cite book|author1=Rafael C. Gonzalez|author2=Richard E. Woods|title=Digital Image Processing|url=https://books.google.com/books?id=8uGOnjRGEzoC|year=2008|publisher=Prentice Hall|isbn=978-0-13-168728-8|pages=1–3}}</ref> Most image-processing techniques involve treating the image as a [[two-dimensional]] [[signal (electrical engineering)|signal]] and applying standard signal-processing techniques to it. Images are also processed as [[three-dimensional]] [[signal (electrical engineering)|signal]]s where the third-dimension being time or the z-axis.
Image processing usually refers to [[digital image processing]], but [[Optical engineering|optical]] and [[analog image processing]] also are possible. This article is about general techniques that apply to all of them. The ''acquisition'' of images (producing the input image in the first place) is referred to as [[Imaging science|imaging]].<ref name="hornak2002">Joseph P. Hornak, ''Encyclopedia of Imaging Science and Technology'' ([[John Wiley & Sons]], 2002) ISBN 9780471332763</ref>
