diff --git a/tools/releasetools/build_super_image.py b/tools/releasetools/build_super_image.py
index 38ea3d6..0150ba1 100755
--- a/tools/releasetools/build_super_image.py
+++ b/tools/releasetools/build_super_image.py
@@ -58,16 +58,8 @@
 UNZIP_PATTERN = ["IMAGES/*", "META/*"]
 
 
-def GetPartitionSizeFromImage(img):
-  try:
-    simg = sparse_img.SparseImage(img)
-    return simg.blocksize * simg.total_blocks
-  except ValueError:
-    return os.path.getsize(img)
-
-
 def GetArgumentsForImage(partition, group, image=None):
-  image_size = GetPartitionSizeFromImage(image) if image else 0
+  image_size = sparse_img.GetImagePartitionSize(image) if image else 0
 
   cmd = ["--partition",
          "{}:readonly:{}:{}".format(partition, image_size, group)]