Patent US 5,489,211

The present invention discloses a method of incorporating at least one copy of a real a cloud into a simulated or real two-dimensional scene by extracting the radiance and transmittance from a real cloud; converting the radiance and transmittance of the cloud to the radiance and transmittance of a desired material such as brass, aluminum, copper, or graphite; adding at least one copy of the resulting cloud to the simulated two-dimensional scene; and scaling each cloud in the simulated two-dimensional scene so that each cloud appears at a desired location. The present invention uses the Atmospheric Transmission Large-Area Analysis System to extract the radiance and transmittance of a real cloud. The present invention can also change the infrared image of a cloud by extracting the radiance and transmittance of the cloud at one wavelength of light. Changing the material of the cloud is accomplished by using Beer's Law to convert the transmittance values to optical depth and recalculating the transmittance using the mass extinction coefficient of the desired material. The cloud in the simulated two-dimensional scene can also be moved within the scene according to the meteorological conditions or topography of the scene.