Transform an RGB form matrix into an XW (space-wavelength) matrix
[XW,r,c,w] = RGB2XWFormat(imRGB);
This routine converts from RGB format to XW format. The row and
column of the imRGB are also returned, if requested.
We say matrices in (r,c,w) format are in RGB format. The dimension, w,
represents the number of data color bands. When w=3, the data are an RGB
image. But w can be almost anything (e.g., 31 wavelength samples from
400:10:700). We use this format frequently for spectral data.
The RGB format is useful for imaging. When w = 3, you can use
conventional image() routines. When w > 3, use imageSPD.
The XW (space-wavelength) format is useful for computation. In this
format, for example, XW*spectralFunction yields a spectral response.
The inverse routine is XW2RGBFormat
See also, imageSPD, imagescRGB, imagescM, XW2RGBFormat
Copyright ImagEval Consultants, LLC, 2003.