update doc

src/interface.jl

@@ -126,6 +126,12 @@ end
     Padding options:
         :buttomRight    will place an image at top-left of a frame(dimension x dimension) and fill
                         the rest of the frame with RGB(0,0,0)
+
+    #Example 
+        using FileIO, Images
+        img = load("test.jpg")
+        img = eltype(img) != RGB{N0f8} ? RGB.(img) : img    # ensure img is in RGB format
+        rescaled_padded_img = imgScalePadding(img, 1024, paddingType=:buttomRight)
 """
 function imgScalePadding(img::T, dimension::Integer; paddingType::Symbol=:none) where T <:DenseMatrix{RGB{N0f8}}
     h, w = size(img)    # high = vertical length, width = horizonal length