Cast an image to different pixel type using SimpleITK

sitk_cast_image.py

import SimpleITK as sitk

image_to_cast = sitk.ReadImage("/path/to/image.nii.gz")
options_for_casting = {
    "int64": sitk.sitkInt64,
    "int32": sitk.sitkInt32,
    "int16": sitk.sitkInt16,
    "int8": sitk.sitkInt8,
    "uint64": sitk.sitkUInt64,
    "uint32": sitk.sitkUInt32,
    "uint16": sitk.sitkUInt16,
    "uint8": sitk.sitkUInt8,    
}
default_casting = "int16"
cast_to_type = default_casting ## change this to the type you want to cast to

image_casted = sitk.Cast(image_to_cast, options_for_casting[cast_to_type])
sitk.WriteImage(image_casted, f"/path/to/image_{cast_to_type}.nii.gz")