Multiplicative Scatter Correction

Features:

Corrects spectra in the datacube.

Steps:

1.    Open a file and select Data Correction Multiplicative scattering correction (MCS).

2.      A pop-up dialogue window will ask to identify a reference spectrum.

3.      Click OK and draw an area. A mean spectrum from this area will serve as a reference spectrum. When selecting an area select a more or less uniform part of the image. After the calculations are complete, visualize the resulting image that is corrected for scattering.

The effect of MSC can be visualized by looking at the individual spectra from one of the objects.

Additional Information:

Performing scattering correction is generally a challenging task and ideally gets rid of all effects that are unrelated to the chemical nature of the sample, but it depends on the sample morphology and measurement geometry. 

Multiplicative scatter correction (MSC) is a widely used classic normalization technique to correct spectra in such a way that they are as close as possible to a reference spectrum. In IDCube the reference spectrum is the mean of the selected area.

MSC requires a reference spectrum. This is the most important difference between MSC and SNV which is also implemented in IDCube.

The reference spectrum is ideally a spectrum free of scattering effects. For the reference spectrum, we suggest selecting a uniform area with minimum changes in morphology. If the spectral data are reasonably uniform, the average spectrum from the area is a close approximation to the ideal reference spectrum. This is the main assumption behind MSC.

Mathematically, if Xm​ is the mean spectrum from the area, the multiplicative scatter correction is done in two steps. We first regress a spectrum for each pixel Xi​  against the mean spectrum.​

References:

Isaksson, Tomas, and Tormod Næs. "The effect of multiplicative scatter correction (MSC) and linearity improvement in NIR spectroscopy." Applied Spectroscopy 42.7 (1988): 1273-1284.

Burger, James, and Paul Geladi. "Spectral pre-treatments of hyperspectral near infrared images: analysis of diffuse reflectance scattering." Journal of Near Infrared Spectroscopy 15.1 (2007): 29-37.