DICOM gray level normalization , 3 sigma normalization

Hi, I am a radiologist who is interests in texture analysis and radomics.
I am a beginner at 3Dslicer. Firstly I want to ask, how can I use 3sigma normalization technique in DICOM images. I don’t know how can ı do it? can you help me?

Some normalization can be done in pyradiomics as part of that analysis:

Or you could use numpy operations on the pixel data to implement the statistics and normalization in a few lines.