diff --git a/skimage/restoration/_denoise.py b/skimage/restoration/_denoise.py
index 16fd07df..c82568f9 100644
--- a/skimage/restoration/_denoise.py
+++ b/skimage/restoration/_denoise.py
@@ -22,8 +22,8 @@ def denoise_bilateral(image, win_size=5, sigma_range=None, sigma_spatial=1,
 
     Parameters
     ----------
-    image : ndarray
-        Input image.
+    image : ndarray, shape (M, N[, 3])
+        Input image, 2D grayscale or RGB.
     win_size : int
         Window size for filtering.
     sigma_range : float