diff --git a/vsmasktools/spat_funcs.py b/vsmasktools/spat_funcs.py
index 40027fb..e86df07 100644
--- a/vsmasktools/spat_funcs.py
+++ b/vsmasktools/spat_funcs.py
@@ -42,7 +42,7 @@ def adg_mask(
 
     assert check_variable(clip, func)
 
-    use_complex = complexpr_available and clip.format.bits_per_sample > 16
+    use_complex = complexpr_available and clip.format.bits_per_sample > 16 or relative
 
     luma, prop = plane(clip, 0), 'P' if use_complex else None
     y, y_inv = luma.std.PlaneStats(prop=prop), luma.std.Invert().std.PlaneStats(prop=prop)