diff --git a/datasets/raise/extract_noise.py b/datasets/raise/extract_noise.py
index c583f48..220540d 100755
--- a/datasets/raise/extract_noise.py
+++ b/datasets/raise/extract_noise.py
@@ -46,13 +46,17 @@ if type_ is not None:
 minColor = None
 maxColor = None
 
-def getImageNpArray(imageFileName, computeExtremes, color):
-    global minColor, maxColor
+def getImageFilePath(imageFileName):
     if raiseNotFlatFields:
         imageFileName = imageFileName.replace('.png', '.NEF')
         imageFilePath = f'{imagesFolderPath}/nef/{imageFileName}'
     else:
         imageFilePath = f'{imagesFolderPath}/{imageFileName}'
+    return imageFilePath
+
+def getImageNpArray(imageFileName, computeExtremes, color):
+    global minColor, maxColor
+    imageFilePath = getImageFilePath(imageFileName)
     imageNpArray = getColorChannel(imageFilePath, color)
 
     if computeExtremes: