get_bit_depth_max refactor

opendm/multispectral.py

@@ -44,14 +44,9 @@ def dn_to_radiance(photo, image):
         image -= dark_level
 
     # Normalize DN to 0 - 1.0
-    bps = photo.bits_per_sample
-    if bps:
-        bit_depth_max = float(2 ** bps)
-    else:
-        # Infer from array dtype
-        info = np.iinfo(image.dtype)
-        bit_depth_max = info.max - info.min
-    image /= bit_depth_max
+    bit_depth_max = photo.get_bit_depth_max()
+    if bit_depth_max:
+        image /= bit_depth_max
 
     if V is not None:
         # vignette correction

opendm/photo.py

@@ -344,8 +344,7 @@ class ODM_Photo:
             # and XMP:SunSensorSensitivity might
             # require additional logic. If these two tags are present, 
             # then sun_sensor is not in physical units?
-
-            return self.sun_sensor / 65535 # uint16 normalized (TODO: is this correct? Documentation from manufacturers is missing)
+            return self.sun_sensor / 65535.0 # normalize uint16 (is this correct?)
         elif self.spectral_irradiance is not None:
             scale = 1.0 # Assumed
             if self.irradiance_scale_to_si is not None:
@@ -356,4 +355,10 @@ class ODM_Photo:
     def get_dls_pose(self):
         if self.dls_yaw is not None:
             return [self.dls_yaw, self.dls_pitch, self.dls_roll]
-        return [0.0, 0.0, 0.0]
+        return [0.0, 0.0, 0.0]
+
+    def get_bit_depth_max(self):
+        if self.bits_per_sample:
+            return float(2 ** self.bits_per_sample)
+
+        return None

stages/run_opensfm.py

@@ -62,7 +62,7 @@ class ODMOpenSfMStage(types.ODM_Stage):
             octx.convert_and_undistort(self.rerun())
         else:
 
-            # TODO: does this work for multi-band RGB images?
+            # TODO: does this work for RGB images?
 
             def radiometric_calibrate(shot_id, image):
                 photo = reconstruction.get_photo(shot_id)