A two-dimensional (2D) image processing program is made to work on 2D images instead of three-dimensional (3D) images, which have different axes. One task of 2D image processing is to manipulate an image, either through a filter or by performing some other change to the image. Another part of 2D image processing is to analyze an image, which can be as specific as a pixel analysis or a broader color or light analysis. When a change or analysis is made, the image processor has to output these changes so they are visible on the computer screen or it can make a report about the image itself.
If someone takes a photo of a real-life area, then that area is in 3D, but the image is only in 2D. This is because the image only has an X- and Y-axis, while a 3D computer image is programmed to have a X-, Y- and Z-axis. While 2D image processing programs may have some 3D features, they are primarily made to work with images that only have two axes. Images can be added to the program through a digital camera, which automatically compresses the image into a workable file, or through a scanner.
Manipulation is one of the main tasks of 2D image processing. This can be any change, such as drawing on the image, changing the color, adding text or applying a gradient. Many changes are made through use of a filter, which goes through the pixels and changes them. For example, a sepia filter takes the original picture’s colors and changes them into a reddish-brown.
Analysis is another import function of 2D image processing. By analyzing the image, the user may be able to uncover hidden information or clear up the image to make it easier to view. For example, medical image processing produces high-contrast images to make it easier to look at blood vessels and bones; meteorologists use filters to change light and wind patterns into visible colors so they can analyze the weather. This helps the user see things the human eye cannot perceive, at least not easily.
After an image is changed or analyzed, it must be outputted. If a screen output is needed, then a 2D image processing program displays the changes on the screen. Report output creates a text report about what was changed or found during the processing; for example, if the 193rd pixel was changed from red to green, the report would highlight that change.