fix casting, add check

Signed-off-by: will tepe <[email protected]>

Author: will tepe

monai/deploy/operators/dicom_series_to_volume_operator.py

@@ -112,7 +112,7 @@ def generate_voxel_data(self, series):
         # with the NumPy array returned from the ITK GetArrayViewFromImage on the image
         # loaded from the same DICOM series.
         vol_data = np.stack([s.get_pixel_array() for s in slices], axis=0)
-        vol_data = vol_data.astype(np.int16)
+        vol_data = vol_data.astype(np.uint16)
 
         # For now we support monochrome image only, for which DICOM Photometric Interpretation
         # (0028,0004) has defined terms, MONOCHROME1 and MONOCHROME2, with the former being:
@@ -156,9 +156,14 @@ def generate_voxel_data(self, series):
 
         if slope != 1:
             vol_data = slope * vol_data.astype(np.float64)
-            vol_data = vol_data.astype(np.int16)
-        vol_data += np.int16(intercept)
-        return np.array(vol_data, dtype=np.int16)
+        vol_data += intercept
+
+        # Check if vol_data can be cast to uint16 without data loss
+        if np.can_cast(vol_data, np.uint16, casting='safe'):
+            vol_data = np.array(vol_data, dtype=np.uint16)
+        else:
+            vol_data = np.array(vol_data, dtype=np.int32)
+        return vol_data
 
     def create_volumetric_image(self, vox_data, metadata):
         """Creates an instance of 3D image.