diff --git a/common/tokenize.gperf b/common/tokenize.gperf
index 0f0d0d6a8..947ccdcbb 100644
--- a/common/tokenize.gperf
+++ b/common/tokenize.gperf
@@ -1,4 +1,5 @@
 align
+alpha
 bar_data_add
 bar_properties_set
 bg
diff --git a/image.c b/image.c
index 38486ae19..06950afad 100644
--- a/image.c
+++ b/image.c
@@ -358,6 +358,10 @@ luaA_image_index(lua_State *L)
         imlib_context_set_image((*image)->image);
         lua_pushnumber(L, imlib_image_get_height());
         break;
+      case A_TK_ALPHA:
+        imlib_context_set_image((*image)->image);
+        lua_pushboolean(L, imlib_image_has_alpha());
+        break;
       default:
         return 0;
     }