matplotlib
diff --git a/‎doc/api/colors_api.rst
Lines changed: 1 addition & 0 deletions b/‎doc/api/colors_api.rst
Lines changed: 1 addition & 0 deletions
diff --git a/‎lib/matplotlib/colorizer.py
Lines changed: 7 additions & 1 deletion b/‎lib/matplotlib/colorizer.py
Lines changed: 7 additions & 1 deletion
@@ -32,6 +32,7 @@ Color norms
    PowerNorm
    SymLogNorm
    TwoSlopeNorm
+   MultiNorm
 
 Univariate Colormaps
 --------------------
 
@@ -154,7 +154,13 @@ def to_rgba(self, x, alpha=None, bytes=False, norm=True):
         # Otherwise run norm -> colormap pipeline
         x = ma.asarray(x)
         if norm:
-            x = self.norm(x)
+            if isinstance(self.norm, colors.MultiNorm):
+                # using structured_output=False gives one less
+                # memcopy operation
+                x = self.norm(x, structured_output=False)
+            else:
+                x = self.norm(x)
+
         rgba = self.cmap(x, alpha=alpha, bytes=bytes)
         return rgba