colorinfrared

Color infrared, often abbreviated as CIR, is a type of false-color imagery produced by a camera sensitive to visible light and near-infrared (NIR) radiation. Standard color photographs record red, green, and blue light. In contrast, a CIR camera typically records green, red, and near-infrared light onto the blue, green, and red layers of the film or sensor, respectively. This mapping creates an image where healthy vegetation appears in vibrant shades of red or pink, as plants reflect NIR light strongly. Water, on the other hand, appears dark blue or black because it absorbs NIR radiation. Soil and barren land typically show up in shades of green, brown, or gray.

The primary application of CIR imagery is in remote sensing, particularly for vegetation analysis. Its ability to distinguish between different types of vegetation and to assess plant health is invaluable in agriculture, forestry, and environmental monitoring. For instance, stressed or diseased vegetation reflects less NIR light, appearing as a duller red or even transitioning to green or blue in the CIR image. This makes CIR imagery a powerful tool for early detection of crop stress, pest infestations, and changes in forest cover. Beyond vegetation, CIR can also be used to differentiate between various soil types and to map water bodies and their turbidity. The distinct spectral signatures captured by CIR provide information that is not readily apparent in standard color photography.