fix: rescale and swap axes to preserve original orientation

nithumb.py

@@ -2,10 +2,13 @@
 
 from __future__ import division
 
+import numpy as np
+
 from argparse import ArgumentParser
 from nibabel import load
 from PIL import Image
 
+
 parser = ArgumentParser(prog='nithumb',
                         description='Generate a thumbnail from a NIfTI file')
 parser.add_argument('inputfile', help='Input NIfTI file')
@@ -13,8 +16,17 @@ parser.add_argument('thumbnail', help='Output thumbnail')
 parsed = parser.parse_args()
 
 image = load(parsed.inputfile).get_data()
+
+imin = np.min(image)
+imax = np.max(image)
+
+image = ((image - imin) / np.float(imax - imin)) * 255.
+
+image = np.swapaxes(image, 0, 1)
+
 image = Image.fromarray(image[:, :, image.shape[2]//2] if image.ndim == 3
                         else image)
+
 image = image.resize([128, 128])
 if image.mode != 'RGB':
   image = image.convert('RGB')