Swapping image bands
Our eyes can only see colors in the visible spectrum as combinations of red, green, and blue (RGB). Air and space-borne sensors can collect wavelengths of the energy outside of the visible spectrum. In order to view this data we move images representing different wavelengths of light reflectance in and out of the RGB channels to make color images. These images often end up as bizarre and alien color combinations that can make visual analysis difficult. An example of a typical satellite image is seen in the following Landsat 7 satellite scene near the NASA Stennis Space Center in Mississippi along the Gulf of Mexico, which is a leading center for Remote Sensing and Geospatial Analysis in general:
Most of the vegetation appears red, and water appears almost black. This image is one type of "false color" image meaning the color of the image is not based on RGB light. However we can change the order of the bands or swap out certain bands to create another type...