Editing Binary image (section)

{{Short description|Image comprising exactly two colors, typically black and white}}
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[[File:Neighborhood watch bw.png|frame|right|A photograph of a [[neighborhood watch]] sign is the foreground color while the rest of the image is the background color.<ref>{{cite news|url=http://www.codersource.net/csharp_color_image_to_binary.aspx |title=Conversion of a Color Image to a Binary Image |publisher=CoderSource.net |date=2005-04-18 |access-date=2008-06-11 |archive-url=https://web.archive.org/web/20080610170124/http://www.codersource.net/csharp_color_image_to_binary.aspx |archive-date=2008-06-10 |url-status=dead }}</ref> In the document-scanning industry, this is often referred to as "bi-tonal".]]

A '''binary image''' is a [[digital image]] that consists of [[pixels]] that can have one of exactly two colors, usually black and white. Each pixel is stored as a single [[bit]] — i.e. either a 0 or 1.

A binary image can be stored in memory as a [[bitmap]]: a packed array of bits. A binary image of 640×480 pixels has a file size of only 37.5 [[Kibibyte|KiB]], and most also compress well with simple [[Run-length encoding|run-length compression]]. A binary image format is often used in contexts where it is important to have a small file size for transmission or storage, or due to color limitations on displays or printers.

It also has technical and artistic applications, for example in [[digital image processing]] and [[pixel art]]. Binary images can be interpreted as [[subset]]s of the [[square lattice|two-dimensional integer lattice]] ''Z''<sup>2</sup>; the field of [[Mathematical morphology|morphological image processing]] was largely inspired by this view.{{Clarify|date=September 2024}}