Fix DICOMSeriesToVolumeOperator casting bug (Project-MONAI#529)

* fix casting, add check

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

* code review changes

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

* fix fir slope as well

---------

Signed-off-by: will tepe <[email protected]>
Co-authored-by: will tepe <[email protected]>
Signed-off-by: Simone Bendazzoli <[email protected]>

Author: 2 people

monai/deploy/operators/dicom_series_to_volume_operator.py

@@ -112,9 +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)
-        # The above get_pixel_array() already considers the PixelRepresentation attribute,
-        # 0 is unsigned int, 1 is signed int
-        if slices[0][0x0028, 0x0103].value == 0:
+        if slices[0][0x0028,0x0103].value == 1:
             vol_data = vol_data.astype(np.uint16)
 
         # For now we support monochrome image only, for which DICOM Photometric Interpretation
@@ -157,35 +155,24 @@ def generate_voxel_data(self, series):
         except KeyError:
             slope = 1
 
+
         # check if vol_data, intercept, and slope can be cast to uint16 without data loss
-        if (
-            np.can_cast(vol_data, np.uint16, casting="safe")
-            and np.can_cast(intercept, np.uint16, casting="safe")
-            and np.can_cast(slope, np.uint16, casting="safe")
-        ):
-            logging.info("Casting to uint16")
+        if np.can_cast(vol_data, np.uint16, casting='safe') and np.can_cast(intercept, np.uint16, casting='safe') and np.can_cast(slope, np.uint16, casting='safe'):
+            logging.info(f"Casting to uint16")
             vol_data = np.array(vol_data, dtype=np.uint16)
             intercept = np.uint16(intercept)
             slope = np.uint16(slope)
-        elif (
-            np.can_cast(vol_data, np.float32, casting="safe")
-            and np.can_cast(intercept, np.float32, casting="safe")
-            and np.can_cast(slope, np.float32, casting="safe")
-        ):
-            logging.info("Casting to float32")
+        elif np.can_cast(vol_data, np.float32, casting='safe') and np.can_cast(intercept, np.float32, casting='safe') and np.can_cast(slope, np.float32, casting='safe'):
+            logging.info(f"Casting to float32")
             vol_data = np.array(vol_data, dtype=np.float32)
             intercept = np.float32(intercept)
             slope = np.float32(slope)
-        elif (
-            np.can_cast(vol_data, np.float64, casting="safe")
-            and np.can_cast(intercept, np.float64, casting="safe")
-            and np.can_cast(slope, np.float64, casting="safe")
-        ):
-            logging.info("Casting to float64")
+        elif np.can_cast(vol_data, np.float64, casting='safe') and np.can_cast(intercept, np.float64, casting='safe') and np.can_cast(slope, np.float64, casting='safe'):
+            logging.info(f"Casting to float64")
             vol_data = np.array(vol_data, dtype=np.float64)
             intercept = np.float64(intercept)
             slope = np.float64(slope)
-
+            
         if slope != 1:
             vol_data = slope * vol_data