diff --git a/Graphics/PDF.hs b/Graphics/PDF.hs
--- a/Graphics/PDF.hs
+++ b/Graphics/PDF.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# LANGUAGE BangPatterns #-}
 ---------------------------------------------------------
 -- |
 -- Copyright   : (c) 2006-2012, alpheccar.org
@@ -83,6 +84,7 @@
 import Data.Binary.Builder(Builder,fromLazyByteString, toLazyByteString)
 import Graphics.PDF.LowLevel.Serializer
 import Data.Monoid
+import Data.List(unfoldr)
 
 -- | Create a new PDF document and return a first page
 -- The page is using the document size by default
@@ -108,7 +110,7 @@
      --myBounds <- gets xobjectBound
      --cp <- gets currentPage
      --let (_,state',w') = runDrawing d (emptyEnvironment {streamId = r, xobjectb = myBounds, currentp = maybe Nothing (\(PDFReference x) -> Just x) cp })
-     let ref = PDFReference r :: PDFReference PDFLength
+     let ref = PDFReference r :: PDFReference MaybeLength
          
      -- Pattern NEEDS a resource entry even if empty otherwise don't work with acrobat reader
      -- Image DON'T want a resource entry if empty otherwise don't work with apple reader
@@ -143,10 +145,12 @@
          let w''' = compress . toLazyByteString $ w'
              w'' = fromLazyByteString w'''
          updateObject (PDFReference k :: PDFReference PDFStream) (PDFStream w'' True ref resources)
-         updateObject ref (PDFLength (B.length w'''))
+         updateObject ref (UnknownLength)
+         --updateObject ref (PDFLength (B.length w'''))
        else do
          updateObject (PDFReference k :: PDFReference PDFStream) (PDFStream w' False ref resources)
-         updateObject ref (PDFLength (B.length . toLazyByteString $ w'))
+         updateObject ref (UnknownLength)
+         --updateObject ref (PDFLength (B.length . toLazyByteString $ w'))
 
 -- | Save all the pages and streams in the main object dictionary
 saveObjects :: PDF (PDFReference PDFCatalog)
@@ -186,6 +190,8 @@
                  , (PDFName "Producer",AnyPdfObject $ toPDFString "HPDF - The Haskell PDF Library" )
                  ]
 
+instance PdfLengthInfo PDFTrailer where
+
 -- | Write PDF objects in the TOC
 writeObjectsAndCreateToc :: [Builder] -- ^ List of objects each object being already converted to a bytestring
                           -> (Int,Int64,[Builder])
@@ -197,7 +203,31 @@
    (length l,last lengths,entries)
 -- foldr writeObject (0,0::Int64,[]) l where
 -- writeObject obj (nb,len,toc) = (nb+1,len + (B.length . toLazyByteString $ obj),(serialize $ (printf "%010d 00000 n \n" ((fromIntegral len)::Integer))) : toc)
-     
+ 
+generateStreams root di !nb !totalLen ens [] = 
+  let entries = reverse (tail ens)  
+  in
+  toLazyByteString $ mconcat $ [ serialize "xref\n"
+                               , serialize $ "0 " ++ show nb ++ "\n"
+                               , serialize "0000000000 65535 f \n"
+                               ]
+                               ++
+                               entries
+                               ++
+                               [ serialize "\ntrailer\n"
+                               , toPDF $ PDFTrailer nb root di
+                               , serialize "\nstartxref\n"
+                               , serialize (show totalLen)
+                               , serialize "\n%%EOF"
+                             ]
+generateStreams root di !nb !totalLen ens (obj:t) = 
+     let s = toLazyByteString obj 
+         createEntry x = serialize $ (printf "%010d 00000 n \n" ((fromIntegral x)::Integer) :: String) 
+         newLen = B.length s + totalLen
+         en = createEntry $! newLen
+     in
+     (s `B.append`) . generateStreams root di (nb+1) newLen (en : ens) $ t
+
 defaultPdfSettings :: PdfState
 defaultPdfSettings = 
   PdfState {
@@ -214,30 +244,46 @@
            , firstOutline = [True]
            }
 
-createObjectByteStrings :: PdfState -> PDF a -> Builder 
+createObjectByteStrings :: PdfState -> PDF a -> B.ByteString 
 createObjectByteStrings pdfState m =
       let header = serialize "%PDF-1.5\n"
-          objectEncoding (x,a) = toPDF . PDFReferencedObject (fromIntegral x) $ a
+          objectEncoding (x,a) = toPDF . PDFReferencedObject (fromIntegral $! x) $ a
           (root,s) = flip runState pdfState  . unPDF $ createPDF >> m >> saveObjects
           objs = objects s
-          objectContents = header : (map objectEncoding . IM.toAscList $ objs)
+          k = IM.keys objs 
+          encodeAnObject (_,[]) = Nothing 
+          encodeAnObject (im,k:t) = 
+            let Just o = IM.lookup k im
+                result = do 
+                    (l,PDFReference ref) <- pdfLengthInfo o 
+                    let im' = IM.insert ref (AnyPdfObject (KnownLength (PDFLength l))) im
+                    return im'
+            in
+            case result of 
+              Nothing -> Just (objectEncoding (k,o),(im,t)) 
+              Just im' ->  Just (objectEncoding (k,o),(im',t)) 
+
+          encodedObjects = unfoldr encodeAnObject (objs,k)
+          objectContents = header : encodedObjects
           (nb,len,toc) = writeObjectsAndCreateToc objectContents
       in
-        mconcat$ objectContents ++
-                [ serialize "xref\n"
-                , serialize $ "0 " ++ show nb ++ "\n"
-                , serialize "0000000000 65535 f \n"
-                ]
-                ++
-                toc
-                ++
-                [ serialize "\ntrailer\n"
-                , toPDF $ PDFTrailer nb root (docInfo pdfState)
-                , serialize "\nstartxref\n"
-                , serialize (show len)
-                , serialize "\n%%EOF"
-                ]
+      generateStreams root (docInfo pdfState) 0 0 [] objectContents 
 
+        --mconcat$ objectContents ++
+        --        [ serialize "xref\n"
+        --        , serialize $ "0 " ++ show nb ++ "\n"
+        --        , serialize "0000000000 65535 f \n"
+        --        ]
+        --        ++
+        --        toc
+        --        ++
+        --        [ serialize "\ntrailer\n"
+        --        , toPDF $ PDFTrailer nb root (docInfo pdfState)
+        --        , serialize "\nstartxref\n"
+        --        , serialize (show len)
+        --        , serialize "\n%%EOF"
+        --        ]
+
 -- | Generate a lazy bytestring for the PDF     
 pdfByteString :: PDFDocumentInfo
               -> PDFRect -- ^ Default size for a page
@@ -245,7 +291,7 @@
               -> IO (B.ByteString) 
 pdfByteString infos rect m = do 
     let content = createObjectByteStrings (defaultPdfSettings {defaultRect = rect, docInfo = infos} ) m
-    return (toLazyByteString content)
+    return content
 
 -- | Generates a PDF document
 runPdf :: String -- ^ Name of the PDF document
diff --git a/Graphics/PDF/Action.hs b/Graphics/PDF/Action.hs
--- a/Graphics/PDF/Action.hs
+++ b/Graphics/PDF/Action.hs
@@ -60,6 +60,8 @@
                          ]
 instance Action GoToURL
 
+instance PdfLengthInfo GoToURL where
+
 
 --instance PdfObject ControlMedia where
 --    toPDF (ControlMedia operation relatedScreenAnnotation rendition) = toPDF . PDFDictionary . M.fromList $
diff --git a/Graphics/PDF/Annotation.hs b/Graphics/PDF/Annotation.hs
--- a/Graphics/PDF/Annotation.hs
+++ b/Graphics/PDF/Annotation.hs
@@ -119,6 +119,8 @@
       toPDF a@(TextAnnotation _ _ i) = toPDF . PDFDictionary . M.fromList $ 
            standardAnnotationDict a ++ [(PDFName "Name",AnyPdfObject . PDFName $ show i)]
 
+instance PdfLengthInfo TextAnnotation where
+
 instance AnnotationObject TextAnnotation where
     addAnnotation = addObject
     annotationType _ = PDFName "Text"
@@ -134,7 +136,9 @@
             [ (PDFName "A",AnyPdfObject (GoToURL url))
             , (PDFName "Border",AnyPdfObject . map AnyPdfObject $ (getBorder border))
             ]
-            
+
+instance PdfLengthInfo URLLink where
+           
 instance AnnotationObject URLLink where
     addAnnotation = addObject
     annotationType _ = PDFName "Link"
@@ -156,6 +160,7 @@
                  , AnyPdfObject y
                  , AnyPdfObject (PDFInteger 0)] 
                                                         
+instance PdfLengthInfo PDFLink where
 
 instance AnnotationObject PDFLink where
     addAnnotation = addObject
diff --git a/Graphics/PDF/Documentation.hs b/Graphics/PDF/Documentation.hs
--- a/Graphics/PDF/Documentation.hs
+++ b/Graphics/PDF/Documentation.hs
@@ -36,8 +36,6 @@
 	-- $warning
 	) where 
 
-import Graphics.PDF
-
 {- $creating 
 
 When you create a document, you must give some information for the PDF file like the author,
diff --git a/Graphics/PDF/Draw.hs b/Graphics/PDF/Draw.hs
--- a/Graphics/PDF/Draw.hs
+++ b/Graphics/PDF/Draw.hs
@@ -88,6 +88,7 @@
 import qualified Data.Map as M
 import qualified Data.IntMap as IM
 import qualified Data.Binary.Builder as BU
+import qualified Data.ByteString.Lazy as B
 
 import Control.Monad.ST
 import Data.STRef
@@ -116,7 +117,8 @@
 
 instance PdfObject AnyAnnotation where
     toPDF (AnyAnnotation a) = toPDF a
-    
+instance PdfLengthInfo AnyAnnotation where
+
 instance AnnotationObject AnyAnnotation where
     addAnnotation (AnyAnnotation a) = do
         PDFReference r <- addAnnotation a
@@ -208,7 +210,7 @@
 modifyDrawST f g = Draw $ \env -> modifySTRef (f env) g
 
 -- | A PDF stream object
-data PDFStream = PDFStream !BU.Builder !Bool !(PDFReference PDFLength) !PDFDictionary
+data PDFStream = PDFStream !BU.Builder !Bool !(PDFReference MaybeLength) !PDFDictionary
                                    
 instance PdfObject PDFStream where
   toPDF (PDFStream s c l d) = 
@@ -223,6 +225,9 @@
       compressedStream True = if not (pdfDictMember (PDFName "Filter") d) then [(PDFName "Filter",AnyPdfObject $ [AnyPdfObject . PDFName $ "FlateDecode"])] else []
       lenDict = PDFDictionary. M.fromList $ [ (PDFName "Length",AnyPdfObject l)] ++ compressedStream c
       dict = pdfDictUnion lenDict d
+
+instance PdfLengthInfo PDFStream where 
+  pdfLengthInfo (PDFStream s _ l _) = Just (B.length . BU.toLazyByteString $ s,l)
     
 -- | An empty drawing
 emptyDrawing :: Draw ()
@@ -326,6 +331,7 @@
 data AnyPdfXForm = forall a. (PDFXObject a,PdfObject a) => AnyPdfXForm a
 instance PdfObject AnyPdfXForm where
     toPDF (AnyPdfXForm a) = toPDF a
+instance PdfLengthInfo AnyPdfXForm where
 
 instance PDFXObject AnyPdfXForm
 
@@ -333,6 +339,8 @@
 instance PDFXObject PDFXForm
 instance PdfObject PDFXForm where
     toPDF _ = noPdfObject
+instance PdfLengthInfo PDFXForm where
+
 instance PdfResourceObject (PDFReference PDFXForm) where
     toRsrc = AnyPdfObject
     
@@ -506,6 +514,8 @@
   , (PDFName "Last",AnyPdfObject lasto)
   ]
 
+instance PdfLengthInfo PDFOutline where
+
 data OutlineStyle = NormalOutline
                   | ItalicOutline
                   | BoldOutline
@@ -550,7 +560,9 @@
    , (PDFName "NonFullScreenPageMode",AnyPdfObject  . PDFName . show $ nfspm)
    ]
 
+instance PdfLengthInfo PDFViewerPreferences where
 
+
 instance Show PDFTransStyle where
    show (Split _ _) = "Split"
    show (Blinds _) = "Blinds"
@@ -576,6 +588,8 @@
     optionalDi (Glitter a)  = [ (PDFName "Di",AnyPdfObject (floatDirection a))]
     optionalDi _ = []  
 
+instance PdfLengthInfo PDFTransition where
+
 -- PDF Pages
 
 instance PdfObject PDFPages where
@@ -591,7 +605,9 @@
   , (PDFName "Count",AnyPdfObject . PDFInteger $ c)
   ] 
 
+instance PdfLengthInfo PDFPages where
 
+
 instance PdfObject PDFPage where
  toPDF (PDFPage (Just theParent) box content theRsrc d t theAnnots) = toPDF $ PDFDictionary. M.fromList $ 
   [ (PDFName "Type",AnyPdfObject (PDFName "Page"))
@@ -608,6 +624,7 @@
   ++ ((\x -> if null x then [] else [(PDFName "Annots",AnyPdfObject x)]) theAnnots)
  toPDF (PDFPage Nothing _ _ _ _ _ _) = noPdfObject
 
+instance PdfLengthInfo PDFPage where
 
 -- Main objects in a PDF document
 
@@ -620,12 +637,15 @@
    , (PDFName "ViewerPreferences", AnyPdfObject viewerPrefs)
    ] ++ (maybe [] (\x -> [(PDFName "Outlines",AnyPdfObject x)]) outlines)
 
+instance PdfLengthInfo PDFCatalog where
 
 instance PdfObject OutlineStyle where
    toPDF NormalOutline = toPDF (PDFInteger 0)
    toPDF ItalicOutline = toPDF (PDFInteger 1)
    toPDF BoldOutline = toPDF (PDFInteger 2)
 
+instance PdfLengthInfo OutlineStyle where
+
 instance PdfObject PDFOutlineEntry where
  toPDF (PDFOutlineEntry title theParent prev next first theLast count dest color style) = 
      toPDF $ PDFDictionary. M.fromList $ [
@@ -647,17 +667,23 @@
       , (PDFName "F",AnyPdfObject style)
       ]
 
+instance PdfLengthInfo PDFOutlineEntry where
 
 
 instance PdfObject Destination where
   toPDF (Destination r) = toPDF                [ AnyPdfObject r
                                                , AnyPdfObject . PDFName $ "Fit"
                                                ]
-                                               
+
+instance PdfLengthInfo Destination where
+
+                                              
 instance PdfObject Color where
    toPDF (Rgb r g b) = toPDF . map AnyPdfObject $ [r,g,b]  
    toPDF (Hsv h s v) = let (r,g,b) = hsvToRgb (h,s,v)
     in toPDF . map AnyPdfObject $ [r,g,b]
+
+instance PdfLengthInfo Color where
 
 -- Degree for a transition direction
 floatDirection :: PDFTransDirection2 -> PDFFloat
diff --git a/Graphics/PDF/Image.hs b/Graphics/PDF/Image.hs
--- a/Graphics/PDF/Image.hs
+++ b/Graphics/PDF/Image.hs
@@ -44,7 +44,7 @@
 import Data.Bits
 import Control.Monad.Error  
 import Graphics.PDF.Coordinates
-import Data.Binary.Builder(Builder,fromLazyByteString)
+import Data.Binary.Builder(Builder,fromLazyByteString,singleton)
 import Control.Exception as E
 import qualified Data.Vector.Unboxed as U
 import qualified Data.Bits as BI
@@ -316,17 +316,16 @@
         recordBound s width height
         return (PDFReference s) 
     where
-       img = fromLazyByteString .  pack24 . U.toList $ stream
-       pack24 :: [Word32] -> B.ByteString
-       pack24 [] = B.empty 
-       pack24 (a:l) = B.cons xa . B.cons xb . B.cons xc $ (pack24 l)
-         where 
-          xa = fromIntegral $ (a `shiftR` 16) .&. 0x0FF
-          xb = fromIntegral $ (a `shiftR` 8) .&. 0x0FF
-          xc = fromIntegral $ (a `shiftR` 0) .&. 0x0FF
-
-       a' = 
-                 do modifyStrict $ \s -> s  {otherRsrcs = PDFDictionary. M.fromList $ 
+        addPixel (a:t) =  
+           let xa = fromIntegral $ (a `shiftR` 16) .&. 0x0FF
+               xb = fromIntegral $ (a `shiftR` 8) .&. 0x0FF
+               xc = fromIntegral $ (a `shiftR` 0) .&. 0x0FF
+           in
+           xa:xb:xc:addPixel t
+        addPixel [] = []
+                        
+        a' =  do 
+                modifyStrict $ \s -> s  {otherRsrcs = PDFDictionary. M.fromList $ 
                                                    [ (PDFName "Type",AnyPdfObject . PDFName $ "XObject")
                                                    , (PDFName "Subtype",AnyPdfObject . PDFName $ "Image")
                                                    , (PDFName "Width",AnyPdfObject . PDFInteger $ round width)
@@ -336,7 +335,7 @@
                                                    , (PDFName "Interpolate", AnyPdfObject interpolate)
                                                    ]
                                              }
-                    tell img        
+                tell . fromLazyByteString . B.pack . addPixel . U.toList $ stream       
 
 -- | A Jpeg file   
 data JpegFile = JpegFile !Int !PDFFloat !PDFFloat !Int !Builder
@@ -351,6 +350,9 @@
         
 instance PdfObject PDFJpeg where
   toPDF _ = noPdfObject
+
+instance PdfLengthInfo PDFJpeg where
+
 instance PdfResourceObject (PDFReference PDFJpeg) where
   toRsrc = AnyPdfObject
 
@@ -365,6 +367,9 @@
         
 instance PdfObject RawImage where
   toPDF _ = noPdfObject
+
+instance PdfLengthInfo RawImage where
+
 instance PdfResourceObject (PDFReference RawImage) where
   toRsrc = AnyPdfObject
 
diff --git a/Graphics/PDF/LowLevel/Types.hs b/Graphics/PDF/LowLevel/Types.hs
--- a/Graphics/PDF/LowLevel/Types.hs
+++ b/Graphics/PDF/LowLevel/Types.hs
@@ -38,51 +38,76 @@
 class PdfObject a where
   toPDF :: a -> Builder
 
+class PdfLengthInfo a where 
+  pdfLengthInfo :: a -> Maybe (Int64 , PDFReference MaybeLength)
+  pdfLengthInfo _ = Nothing
+
 -- | Anonymous PDF object
-data AnyPdfObject = forall a . PdfObject a => AnyPdfObject a
+data AnyPdfObject = forall a . (PdfObject a, PdfLengthInfo a) => AnyPdfObject !a
 
 instance PdfObject AnyPdfObject where
  toPDF (AnyPdfObject a) = toPDF a
+
+instance PdfLengthInfo AnyPdfObject where 
+  pdfLengthInfo (AnyPdfObject a) = pdfLengthInfo a
  
 -- | An integer in a PDF document
 newtype PDFInteger = PDFInteger Int deriving(Eq,Show,Ord,Num)
 
 -- | A length in a PDF document
-data PDFLength = PDFLength Int64 deriving(Eq,Show,Ord)
+newtype PDFLength = PDFLength Int64 deriving(Eq,Show,Ord,Num)
 
-instance Num PDFLength where
-  (+) (PDFLength a) (PDFLength b) = PDFLength (a+b)
-  (*) (PDFLength a) (PDFLength b) = PDFLength (a*b)
-  negate (PDFLength a) = PDFLength (negate a)
-  abs (PDFLength a) = PDFLength (abs a)
-  signum (PDFLength a) = PDFLength (signum a)
-  fromInteger a = PDFLength (fromInteger a)
+data MaybeLength = UnknownLength 
+                 | KnownLength !PDFLength 
 
+instance PdfObject MaybeLength where 
+  toPDF (KnownLength a) = toPDF a 
+  toPDF (UnknownLength) = error "Trying to process an unknown length during PDF generation"
+
+instance PdfLengthInfo MaybeLength where
+
 -- | A real number in a PDF document
 type PDFFloat = Double 
 
 instance PdfObject PDFInteger where
     toPDF (PDFInteger a) = serialize a
 
+instance PdfLengthInfo PDFInteger where
+
 instance PdfObject Int where
     toPDF a = serialize a
+
+instance PdfLengthInfo Int where
+
           
 instance PdfObject PDFLength where
     toPDF (PDFLength a) = serialize (show a)
+
+instance PdfLengthInfo PDFLength where
+
     
 instance PdfObject PDFFloat where
   toPDF a = serialize a
 
+instance PdfLengthInfo PDFFloat where
+
+
 instance PdfObject (Complex PDFFloat) where
   toPDF (x :+ y) = mconcat [ serialize x
                            , serialize ' '
                            , serialize y
                            ] 
+
+instance PdfLengthInfo (Complex PDFFloat) where
+
   
 instance PdfObject Bool where
   toPDF (True) = serialize "true"
   toPDF (False) = serialize "false"
 
+instance PdfLengthInfo Bool where
+
+
 -- | A PDFString containing a strict bytestring
 newtype PDFString = PDFString S.ByteString deriving(Eq,Ord,Show)
 
@@ -155,18 +180,26 @@
                     , rparen
                     ]
 
+instance PdfLengthInfo PDFString where
+
+
 -- | A PDFName object
 newtype PDFName = PDFName String deriving(Eq,Ord)
 
 instance PdfObject PDFName where
  toPDF (PDFName a) = serialize ("/" ++ a)
+
+instance PdfLengthInfo PDFName where
+
  
 -- | A PDFArray
 type PDFArray = [AnyPdfObject]
 
 instance PdfObject a => PdfObject [a] where
     toPDF l = mconcat $ (lbracket:intersperse bspace (map toPDF l)) ++ [bspace] ++ [rbracket]
-                                 
+       
+instance PdfObject a => PdfLengthInfo [a] where
+
 -- | A PDFDictionary
 
 newtype PDFDictionary = PDFDictionary (M.Map PDFName AnyPdfObject)
@@ -185,7 +218,9 @@
                                                                        
           in 
            M.foldWithKey convertItem mempty a
-           
+  
+instance PdfLengthInfo PDFDictionary where
+
 -- | Am empty dictionary
 emptyDictionary :: PDFDictionary
 emptyDictionary = PDFDictionary M.empty
@@ -206,6 +241,8 @@
 instance PdfObject PDFRect where
  toPDF (PDFRect a b c d) = toPDF . map (AnyPdfObject . PDFInteger) $ [a,b,c,d]
  
+instance PdfLengthInfo PDFRect where
+
       
 -- | A Referenced objects
 data PDFReferencedObject a = PDFReferencedObject !Int !a
@@ -220,6 +257,9 @@
                , serialize "endobj"
                , newline , newline
                ]
+
+instance PdfObject a => PdfLengthInfo (PDFReferencedObject a) where
+
                
 -- | A reference to a PDF object
 data PDFReference s = PDFReference !Int deriving(Eq,Ord,Show)
@@ -241,10 +281,13 @@
                                      , serialize " 0 R"]
                                       
                                    
+instance PdfObject s => PdfLengthInfo (PDFReference s) where
                
 instance (PdfObject a,PdfObject b) => PdfObject (Either a b) where
   toPDF (Left a) = toPDF a
   toPDF (Right a) = toPDF a
+
+instance (PdfObject a, PdfObject b) => PdfLengthInfo (Either a b) where
 
 modifyStrict :: (MonadState s m) => (s -> s) -> m ()
 modifyStrict f = do
diff --git a/Graphics/PDF/Pages.hs b/Graphics/PDF/Pages.hs
--- a/Graphics/PDF/Pages.hs
+++ b/Graphics/PDF/Pages.hs
@@ -91,7 +91,7 @@
           return r
      
 -- | Add an object to the PDF object dictionary and return a PDF reference     
-addObject :: (PdfObject a) => a -> PDF (PDFReference a)
+addObject :: (PdfObject a, PdfLengthInfo a) => a -> PDF (PDFReference a)
 addObject a = do
   r <- supply
   modifyStrict $ \s -> s {objects = IM.insert r (AnyPdfObject a) (objects s)}
@@ -99,7 +99,7 @@
   
 
 -- | Update a referenced object with a new one
-updateObject :: (PdfObject a) => PDFReference a -- ^ Reference to the initial object
+updateObject :: (PdfObject a, PdfLengthInfo a) => PDFReference a -- ^ Reference to the initial object
              -> a -- ^ New value
              -> PDF ()
 updateObject (PDFReference i) obj = do
diff --git a/Graphics/PDF/Resources.hs b/Graphics/PDF/Resources.hs
--- a/Graphics/PDF/Resources.hs
+++ b/Graphics/PDF/Resources.hs
@@ -106,7 +106,9 @@
 
 instance PdfObject PDFResource where
  toPDF r = toPDF . resourceToDict $ r
-        
+     
+instance PdfLengthInfo PDFResource where
+
 -- | Add a new G State to the G State dictionary for the given resource
 addResource :: PDFName -- ^ GState dictionary
           -> PDFName -- ^ GState name must be unique
@@ -142,16 +144,22 @@
     
 instance PdfObject PDFColoredPattern where
     toPDF _ = noPdfObject
+instance PdfLengthInfo PDFColoredPattern where
+
 instance PdfResourceObject (PDFReference PDFColoredPattern) where
     toRsrc = AnyPdfObject
 
 instance PdfObject PDFUncoloredPattern where
         toPDF _ = noPdfObject
+instance PdfLengthInfo PDFUncoloredPattern where
+
 instance PdfResourceObject (PDFReference PDFUncoloredPattern) where
         toRsrc = AnyPdfObject
 
 instance PdfObject AnyPdfPattern where
         toPDF _ = noPdfObject
+instance PdfLengthInfo AnyPdfPattern where
+
 instance PdfResourceObject (PDFReference AnyPdfPattern) where
         toRsrc = AnyPdfObject
 
diff --git a/HPDF.cabal b/HPDF.cabal
--- a/HPDF.cabal
+++ b/HPDF.cabal
@@ -1,5 +1,5 @@
 Name: HPDF
-Version: 1.4.4
+Version: 1.4.5
 cabal-version: >=1.6
 License: LGPL
 License-file:LICENSE
diff --git a/Test/Makefile b/Test/Makefile
--- a/Test/Makefile
+++ b/Test/Makefile
@@ -1,11 +1,11 @@
 debug:
-	ghc -o test -XForeignFunctionInterface -cpp -Wall -funbox-strict-fields  -fglasgow-exts  -O2 -hidir interfaces -odir bin -optc-I../c -i.. ../c/metrics.c ../c/conversion.c --make test.hs
+	ghc -o test -O -package-db ../dist/package.conf.inplace --make test.hs
 
 profile:
-	ghc -o test -prof -auto-all -XForeignFunctionInterface -cpp -Wall -funbox-strict-fields  -fglasgow-exts  -O2 -hidir interfaces -odir bin -optc-I../c -i..  ../c/metrics.c ../c/conversion.c --make test.hs
+	ghc -o test -prof -fprof-auto -rtsopts -O -package-db ../dist/package.conf.inplace --make test.hs
 	
 runprof:
-	./test +RTS -p -hc
+	./test +RTS -p -hy
 		
 demo:
 	ghc -o test -O2 --make test.hs