Color image processing is the analysis, transformation, and interpretation of visual data presented in color. It can produce a range of results from a grayscale conversion of a black and white picture to a detailed analysis of information contained in a photograph taken by a telescope. Digital image processing can involve the use of a variety of programs as well as manual activities performed by people with programming skills. Research and development in this area is ongoing at facilities in private companies as well as academic institutions.
There are a number of applications for color image processing. In image acquisition, where an image is actually taken, whether it is committed to film or stored on a digital device, errors can creep in, or it may be necessary to analyze the image in some way to collect meaningful information. For example, in magnetic resonance imaging, a computer must take the output from the MRI and provide it in a visible form for the user, a form of processing. The program can also perform activities like color-coding areas of the scan for added contrast and visibility.
Some color images require correction of some form before they are ready for use. Image processing of this nature can range from cropping to achieve a more visually interesting image to manual color correction in a corrupted or damaged image. This occurs to prepare pictures for publication and distribution; photographs straight out of a camera may not be suitable for the intended use. Preparation of images for publication can also include conversion to a color pattern used at a printer's, like the RGB color scheme used in offset printing to produce color images.
In addition to being useful for getting images ready for distribution, color image processing can be used for analysis. Astronomers, for instance, use the images of space they collect with telescopes, balloons, and satellites to make important observations about the universe. They may turn to automated color image processing software to help them pick targets of interest and highlight phenomena they might miss by looking at the image. Advanced programs can also engage in activities like counting objects in a picture, or providing information about which areas of the spectrum are present.
Handling of color images can be more complex than that of black and whites, from a processing perspective. In color image processing, tools like filtering and layering may be necessary to clean out noise that obscures the color, clarity, or function of the image. These tools are used in everything from the restoration of historic photographs to processing test results with an imaging component.