Slope

Slope will fit a curve to the spectral variation of an image over a few wavelengths of illumination.

Slope reads in a single multiband image. The wavelengths of each band are specified in the “wavelengths” entry. There are three different curves that can be fit to the spectral data, linear, parabola, and cubic. A ”linear” fit can output two bands with the parameters of “slope” and “intercept”. A parabolic fit will output three parameters, and a cubic fit will output 4. The default is to put out all the parameters in multiple bands, but individual bands can be individually specified.

A “linear” fit can output two bands. A “parabolic” fit can output three bands. A “cubic” fit can output four bands. To make these fits, the number of input bands (wavelengths) that are two for “linear”, three for “parabola”, and four for “cubic”.

If the output “format” of “parameters” is chosen, then 2, 3, or 4 bands are output. If instead “image” is chosen, then a single band is output in which the fit is used to calculate the response at a desired output wavelength.