Definition: Multispectral Imaging
Multispectral surveys image the earth in an average of ten wide bands over a wide spectral range. Multispectral sensors measure the electromagnetic spectrum in discrete, discontinuous bands (unlike the continuous hyperspectral image). Multispectral sensors are capable of relative material delineation. The thermal wavelength range of the multispectral survey senses heat energy from the Earth's surface. It can be used to sense surface temperature, including anomalies associated with active geothermal or volcanic systems. Both multispectral and hyperspectral remote sensing observations are available. This range can also be used to map mineralogy associate with common rock-forming silicates.
- A multispectral image is one that captures image data within specific wavelength ranges across the electromagnetic spectrum. The wavelengths may be separated by filters or by the use of instruments that are sensitive to particular wavelengths, including light from frequencies beyond the visible light range, i.e. infrared and ultra-violet. Spectral imaging can allow extraction of additional information the human eye fails to capture with its receptors for red, green and blue. It was originally developed for space-based imaging, and has also found use in document and painting analysis.Multispectral imaging measures light in a small number (typically 3 to 15) of spectral bands. Hyperspectral imaging is a special case of spectral imaging where often hundreds of contiguous spectral bands are available.