How to understand the SliceToRAS matrix?


It seems that there are a lot of coordinate systems involved in Slicer. :grinning:
I was trying to find a tutorial explaining the different coordinate systems and transformations among each other, however, failed to find a good one.


  1. How many Coordinate Systems (CSs) are involved Slicer? (e.g., IJK, XYZ, SliceNode? VolumeNode? RAS? LAS, LPI, RPI…)

  2. How are those CSs employed in Slicer? (e.g., what exactly is a coordinate of Slice? and what does the matrix of SliceToRAS do?)

  3. Any resource or tutorial that explains how the principles of different transformation matrixes mathematically?

Thank you very much!

Hi -

This is a good place to start:

Thank you for providing this link, Pieper!

Yes, that is a good place to start; though it could not answer my questions systematically. :stuck_out_tongue_winking_eye: