diff --git a/autoload/zencoding/lang/haml.vim b/autoload/zencoding/lang/haml.vim
index 534f749..def19a4 100644
--- a/autoload/zencoding/lang/haml.vim
+++ b/autoload/zencoding/lang/haml.vim
@@ -99,7 +99,9 @@ function! zencoding#lang#haml#imageSize()
     return
   endif
   let fn = current.attr.src
-  if fn !~ '^\(/\|http\)'
+  if fn =~ '^\s*$'
+    return
+  elseif fn !~ '^\(/\|http\)'
     let fn = simplify(expand('%:h') . '/' . fn)
   endif
 
diff --git a/autoload/zencoding/lang/html.vim b/autoload/zencoding/lang/html.vim
index 4a4d38b..bf2b825 100644
--- a/autoload/zencoding/lang/html.vim
+++ b/autoload/zencoding/lang/html.vim
@@ -387,7 +387,9 @@ function! zencoding#lang#html#imageSize()
     return
   endif
   let fn = current.attr.src
-  if fn !~ '^\(/\|http\)'
+  if fn =~ '^\s*$'
+    return
+  elseif fn !~ '^\(/\|http\)'
     let fn = simplify(expand('%:h') . '/' . fn)
   endif
 
diff --git a/autoload/zencoding/lang/slim.vim b/autoload/zencoding/lang/slim.vim
index 4a0301e..c2a5bb1 100644
--- a/autoload/zencoding/lang/slim.vim
+++ b/autoload/zencoding/lang/slim.vim
@@ -78,7 +78,9 @@ function! zencoding#lang#slim#imageSize()
     return
   endif
   let fn = current.attr.src
-  if fn !~ '^\(/\|http\)'
+  if fn =~ '^\s*$'
+    return
+  elseif fn !~ '^\(/\|http\)'
     let fn = simplify(expand('%:h') . '/' . fn)
   endif