Normalization/calibration

[Hamburgerfinger]

What is the best way to apply a normalization or calibration factor to an image volume? (I.e. just multiply all voxel scalars by a constant)

It seems like a good place for this would be the “Volumes” node.

Thanks!
Luke

[lassoan (Andras Lasso)]

You can click and drag in any of the slice viewers to apply linear scaling/offset to the displayed volume.

[Hamburgerfinger]

But this just changes the color mapping. I want to actually modify the values present in the dataset by scalar multiplication.

For instance, if the image is quantified in units of (signal)/(unit volume) and I want (signal)/(unit mass), it’s necessary to multiply by a calibration factor (inverse of the density).

[jcfr (Jean Christophe Fillion Robin (Kitware))]

@Hamburgerfinger

to actually modify the values present in the dataset by scalar multiplication.

This should be helpful: Documentation/Nightly/Developers/Python scripting - Slicer Wiki

[fedorov (Andrey Fedorov)]

If you prefer to use the GUI for that operation, you can use ShiftScaleImageFilter from the SimpleFilters module:

[Hamburgerfinger]

Thanks, this is exactly what I wanted!

Best,
Luke