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. To view this data, we must 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 shown in the following Landsat 7 satellite scene along the Gulf of Mexico, which is a leading center for remote sensing and geospatial analysis in general:
Figure 7.1 – A false-color satellite image along the Gulf of Mexico
Most of the vegetation appears red and the water appears almost black. This image is a type of false-color image, meaning the color of the image is not based on the RGB light. However, we can change the order of the...
