diff --git a/cpdf.ml b/cpdf.ml
index 7218ae8..e3931f9 100644
--- a/cpdf.ml
+++ b/cpdf.ml
@@ -4488,3 +4488,164 @@ let image_resolution pdf range dpi =
   image_results := [];
   image_resolution pdf range dpi;
   rev !image_results
+
+(* copy the contents of the box f to the box t. If mediabox_if_missing is set,
+the contents of the mediabox will be used if the from fox is not available. If
+mediabox_is_missing is false, the page is unaltered. *)
+let copy_box f t mediabox_if_missing pdf range =
+  process_pages
+    (ppstub (fun _ page ->
+       if f = "/MediaBox" then
+         {page with Pdfpage.rest =
+            (Pdf.add_dict_entry page.Pdfpage.rest t (page.Pdfpage.mediabox))}
+       else
+         match Pdf.lookup_direct pdf f page.Pdfpage.rest with
+         | Some pdfobject ->
+             if t = "/MediaBox"
+               then {page with
+                       Pdfpage.mediabox = Pdf.direct pdf pdfobject}
+               else {page with Pdfpage.rest =
+                       (Pdf.add_dict_entry page.Pdfpage.rest t (Pdf.direct pdf pdfobject))}
+         | None ->
+             if mediabox_if_missing
+               then {page with Pdfpage.rest = Pdf.add_dict_entry page.Pdfpage.rest t page.Pdfpage.mediabox}
+               else page))
+    pdf
+    range
+
+let dump_attachment out pdf (_, embeddedfile) =
+  match Pdf.lookup_direct pdf "/F" embeddedfile with
+  | Some (Pdf.String s) ->
+      let efdata =
+        begin match Pdf.lookup_direct pdf "/EF" embeddedfile with
+        | Some d ->
+            let stream =
+              match Pdf.lookup_direct pdf "/F" d with
+              | Some s -> s
+              | None -> error "Bad embedded file stream"
+            in
+              Pdfcodec.decode_pdfstream_until_unknown pdf stream;
+              begin match stream with Pdf.Stream {contents = (_, Pdf.Got b)} -> b | _ -> error "Bad embedded file stream" end
+        | _ -> error "Bad embedded file stream"
+        end
+      in
+        let s = remove_unsafe_characters s in
+        let filename = if out = "" then s else out ^ Filename.dir_sep ^ s in
+        begin try
+          let fh = open_out_bin filename in
+            for x = 0 to bytes_size efdata - 1 do output_byte fh (bget efdata x) done;
+            close_out fh
+        with
+          e -> Printf.eprintf "Failed to write attachment to %s\n%!" filename;
+        end
+  | _ -> ()
+
+let dump_attached_document pdf out =
+  let root = Pdf.lookup_obj pdf pdf.Pdf.root in
+    let names =
+      match Pdf.lookup_direct pdf "/Names" root with Some n -> n | _ -> Pdf.Dictionary []
+    in
+      match Pdf.lookup_direct pdf "/EmbeddedFiles" names with
+      | Some x ->
+          iter (dump_attachment out pdf) (Pdf.contents_of_nametree pdf x)
+      | None -> () 
+
+let dump_attached_page pdf out page =
+  let annots =
+    match Pdf.lookup_direct pdf "/Annots" page.Pdfpage.rest with
+    | Some (Pdf.Array l) -> l
+    | _ -> []
+  in
+    let efannots =
+      keep
+        (fun annot ->
+           match Pdf.lookup_direct pdf "/Subtype" annot with
+           | Some (Pdf.Name "/FileAttachment") -> true
+           | _ -> false)
+        annots
+    in
+      let fsannots = option_map (Pdf.lookup_direct pdf "/FS") efannots in
+        iter (dump_attachment out pdf) (map (fun x -> 0, x) fsannots)
+
+(* Dump both document-level and page-level attached files to file, using their file names *)
+let dump_attached_files pdf out =
+  try
+    dump_attached_document pdf out;
+    iter (dump_attached_page pdf out) (Pdfpage.pages_of_pagetree pdf)
+  with
+    e -> error (Printf.sprintf "Couldn't dump attached files: %s\n" (Printexc.to_string e))
+
+let remove_unused_resources_page pdf n page =
+  let xobjects, all_names =
+    match Pdf.lookup_direct pdf "/XObject" page.Pdfpage.resources with
+    | Some (Pdf.Dictionary d) -> Pdf.Dictionary d, map fst d
+    | _ -> Pdf.Dictionary [], []
+  in
+    let names_to_keep =
+      option_map
+        (function Pdfops.Op_Do n -> Some n | _ -> None)
+        (Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content)
+    in
+      let names_to_remove = lose (mem' names_to_keep) all_names in
+        let xobjdict = fold_left (Pdf.remove_dict_entry) xobjects names_to_remove in
+          {page with Pdfpage.resources = Pdf.add_dict_entry page.Pdfpage.resources  "/XObject" xobjdict}
+
+let remove_unused_resources pdf =
+  process_pages (ppstub (remove_unused_resources_page pdf)) pdf (ilist 1 (Pdfpage.endpage pdf))
+
+let print_spot_colour n s =
+  Printf.printf "%i %s\n" n s
+
+let list_spot_colours pdf =
+  Pdf.objiter
+    (fun _ obj ->
+       match obj with
+         Pdf.Array (Pdf.Name "/Separation"::x::_) ->
+           begin match Pdf.direct pdf x with
+             Pdf.Name col -> Printf.printf "%s\n" col
+           | _ -> ()
+           end
+       | _ -> ())
+    pdf
+
+(* Indent bookmarks in each file by one and add a title bookmark pointing to the first page. *)
+let add_bookmark_title filename use_title pdf =
+  let title =
+    if use_title then
+      match get_info_utf8 pdf "/Title", get_xmp_info pdf "/Title" with
+        "", x | x, "" | _, x -> x
+    else
+      Filename.basename filename
+  in
+  let marks = Pdfmarks.read_bookmarks pdf in
+  let page1objnum =
+    match Pdfpage.page_object_number pdf 1 with
+      None -> error "add_bookmark_title: page not found"
+    | Some x -> x
+  in
+  let newmarks =
+      {Pdfmarks.level = 0;
+       Pdfmarks.text = title;
+       Pdfmarks.target = Pdfdest.XYZ (Pdfdest.PageObject page1objnum, None, None, None);
+       Pdfmarks.isopen = false}
+    ::map (function m -> {m with Pdfmarks.level = m.Pdfmarks.level + 1}) marks
+  in
+    Pdfmarks.add_bookmarks newmarks pdf
+
+let bookmarks_open_to_level n pdf =
+  let marks = Pdfmarks.read_bookmarks pdf in
+  let newmarks =
+    map
+      (fun m -> {m with Pdfmarks.isopen = m.Pdfmarks.level < n})
+      marks
+  in
+    Pdfmarks.add_bookmarks newmarks pdf
+
+let create_pdf pages pagesize =
+  let page =
+    {(Pdfpage.blankpage pagesize) with
+        Pdfpage.content = [Pdfops.stream_of_ops []];
+        Pdfpage.resources = Pdf.Dictionary []}
+  in
+    let pdf, pageroot = Pdfpage.add_pagetree (many page pages) (Pdf.empty ()) in
+      Pdfpage.add_root pageroot [] pdf
diff --git a/cpdf.mli b/cpdf.mli
index e73beae..636d555 100644
--- a/cpdf.mli
+++ b/cpdf.mli
@@ -397,3 +397,18 @@ val print_dict_entry : Pdf.t -> string -> unit
 val remove_clipping : Pdf.t -> int list -> Pdf.t 
 
 val image_resolution : Pdf.t -> int list -> float -> (int * string * int * int * float * float) list
+
+val copy_box : string -> string -> bool -> Pdf.t -> int list -> Pdf.t
+
+val dump_attached_files : Pdf.t -> string -> unit
+
+val add_bookmark_title : string -> bool -> Pdf.t -> Pdf.t
+
+val remove_unused_resources : Pdf.t -> Pdf.t
+
+val list_spot_colours : Pdf.t -> unit
+
+val bookmarks_open_to_level : int -> Pdf.t -> Pdf.t
+
+val create_pdf : int -> Pdfpaper.t -> Pdf.t
+
diff --git a/cpdfcommand.ml b/cpdfcommand.ml
index c92d1fb..01c0982 100644
--- a/cpdfcommand.ml
+++ b/cpdfcommand.ml
@@ -915,9 +915,6 @@ let anon_fun s =
 (* If a password begins with a dash, we allow -pw=<password> too *)
 let setdashpassword = anon_fun
 
-(*let firstpage pdf =
-  List.hd (Pdfpage.pages_of_pagetree pdf)*)
-
 (* Setting operations *)
 let setcrop s =
   setop Crop ();
@@ -3056,93 +3053,6 @@ let getencryption pdf =
   | Some (Pdfwrite.AES256bitISO true) -> "256bit AES ISO, Metadata encrypted"
   | Some (Pdfwrite.AES256bitISO false) -> "256bit AES ISO, Metadata not encrypted"
 
-
-(* copy the contents of the box f to the box t. If mediabox_if_missing is set,
-the contents of the mediabox will be used if the from fox is not available. If
-mediabox_is_missing is false, the page is unaltered. *)
-let copy_box f t mediabox_if_missing pdf range =
-  Cpdf.process_pages
-    (ppstub (fun _ page ->
-       if f = "/MediaBox" then
-         {page with Pdfpage.rest =
-            (Pdf.add_dict_entry page.Pdfpage.rest t (page.Pdfpage.mediabox))}
-       else
-         match Pdf.lookup_direct pdf f page.Pdfpage.rest with
-         | Some pdfobject ->
-             if t = "/MediaBox"
-               then {page with
-                       Pdfpage.mediabox = Pdf.direct pdf pdfobject}
-               else {page with Pdfpage.rest =
-                       (Pdf.add_dict_entry page.Pdfpage.rest t (Pdf.direct pdf pdfobject))}
-         | None ->
-             if mediabox_if_missing
-               then {page with Pdfpage.rest = Pdf.add_dict_entry page.Pdfpage.rest t page.Pdfpage.mediabox}
-               else page))
-    pdf
-    range
-
-let dump_attachment out pdf (_, embeddedfile) =
-  match Pdf.lookup_direct pdf "/F" embeddedfile with
-  | Some (Pdf.String s) ->
-      let efdata =
-        begin match Pdf.lookup_direct pdf "/EF" embeddedfile with
-        | Some d ->
-            let stream =
-              match Pdf.lookup_direct pdf "/F" d with
-              | Some s -> s
-              | None -> error "Bad embedded file stream"
-            in
-              Pdfcodec.decode_pdfstream_until_unknown pdf stream;
-              begin match stream with Pdf.Stream {contents = (_, Pdf.Got b)} -> b | _ -> error "Bad embedded file stream" end
-        | _ -> error "Bad embedded file stream"
-        end
-      in
-        let s = remove_unsafe_characters s in
-        let filename = if out = "" then s else out ^ Filename.dir_sep ^ s in
-        begin try
-          let fh = open_out_bin filename in
-            for x = 0 to bytes_size efdata - 1 do output_byte fh (bget efdata x) done;
-            close_out fh
-        with
-          e -> Printf.eprintf "Failed to write attachment to %s\n%!" filename;
-        end
-  | _ -> ()
-
-let dump_attached_document pdf out =
-  let root = Pdf.lookup_obj pdf pdf.Pdf.root in
-    let names =
-      match Pdf.lookup_direct pdf "/Names" root with Some n -> n | _ -> Pdf.Dictionary []
-    in
-      match Pdf.lookup_direct pdf "/EmbeddedFiles" names with
-      | Some x ->
-          iter (dump_attachment out pdf) (Pdf.contents_of_nametree pdf x)
-      | None -> () 
-
-let dump_attached_page pdf out page =
-  let annots =
-    match Pdf.lookup_direct pdf "/Annots" page.Pdfpage.rest with
-    | Some (Pdf.Array l) -> l
-    | _ -> []
-  in
-    let efannots =
-      keep
-        (fun annot ->
-           match Pdf.lookup_direct pdf "/Subtype" annot with
-           | Some (Pdf.Name "/FileAttachment") -> true
-           | _ -> false)
-        annots
-    in
-      let fsannots = option_map (Pdf.lookup_direct pdf "/FS") efannots in
-        iter (dump_attachment out pdf) (map (fun x -> 0, x) fsannots)
-
-(* Dump both document-level and page-level attached files to file, using their file names *)
-let dump_attached_files pdf out =
-  try
-    dump_attached_document pdf out;
-    iter (dump_attached_page pdf out) (Pdfpage.pages_of_pagetree pdf)
-  with
-    e -> error (Printf.sprintf "Couldn't dump attached files: %s\n" (Printexc.to_string e))
-
 (* If pages in stamp < pages in main, extend stamp by repeating its last page. If pages in stamp more, chop stamp *)
 let equalize_pages_extend main stamp =
   let length_stamp = Pdfpage.endpage stamp
@@ -3156,81 +3066,6 @@ let equalize_pages_extend main stamp =
       then chop stamp length_main
       else extend_lastpage (last (Pdfpage.pages_of_pagetree stamp)) stamp (length_main - length_stamp)
 
-let remove_unused_resources_page pdf n page =
-  let xobjects, all_names =
-    match Pdf.lookup_direct pdf "/XObject" page.Pdfpage.resources with
-    | Some (Pdf.Dictionary d) -> Pdf.Dictionary d, map fst d
-    | _ -> Pdf.Dictionary [], []
-  in
-    let names_to_keep =
-      option_map
-        (function Pdfops.Op_Do n -> Some n | _ -> None)
-        (Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content)
-    in
-      let names_to_remove = lose (mem' names_to_keep) all_names in
-        let xobjdict = fold_left (Pdf.remove_dict_entry) xobjects names_to_remove in
-          {page with Pdfpage.resources = Pdf.add_dict_entry page.Pdfpage.resources  "/XObject" xobjdict}
-
-let remove_unused_resources pdf =
-  Cpdf.process_pages (ppstub (remove_unused_resources_page pdf)) pdf (ilist 1 (Pdfpage.endpage pdf))
-
-let print_spot_colour n s =
-  Printf.printf "%i %s\n" n s
-
-let list_spot_colours pdf =
-  Pdf.objiter
-    (fun _ obj ->
-       match obj with
-         Pdf.Array (Pdf.Name "/Separation"::x::_) ->
-           begin match Pdf.direct pdf x with
-             Pdf.Name col -> Printf.printf "%s\n" col
-           | _ -> ()
-           end
-       | _ -> ())
-    pdf
-
-(* Indent bookmarks in each file by one and add a title bookmark pointing to the first page. *)
-let add_bookmark_title filename use_title pdf =
-  let title =
-    if use_title then
-      match Cpdf.get_info_utf8 pdf "/Title", Cpdf.get_xmp_info pdf "/Title" with
-        "", x | x, "" | _, x -> x
-    else
-      Filename.basename filename
-  in
-  let marks = Pdfmarks.read_bookmarks pdf in
-  let page1objnum =
-    match Pdfpage.page_object_number pdf 1 with
-      None -> error "add_bookmark_title: page not found"
-    | Some x -> x
-  in
-  let newmarks =
-      {Pdfmarks.level = 0;
-       Pdfmarks.text = title;
-       Pdfmarks.target = Pdfdest.XYZ (Pdfdest.PageObject page1objnum, None, None, None);
-       Pdfmarks.isopen = false}
-    ::map (function m -> {m with Pdfmarks.level = m.Pdfmarks.level + 1}) marks
-  in
-    Pdfmarks.add_bookmarks newmarks pdf
-
-let bookmarks_open_to_level n pdf =
-  let marks = Pdfmarks.read_bookmarks pdf in
-  let newmarks =
-    map
-      (fun m -> {m with Pdfmarks.isopen = m.Pdfmarks.level < n})
-      marks
-  in
-    Pdfmarks.add_bookmarks newmarks pdf
-
-let create_pdf pages pagesize =
-  let page =
-    {(Pdfpage.blankpage args.createpdf_pagesize) with
-        Pdfpage.content = [Pdfops.stream_of_ops []];
-        Pdfpage.resources = Pdf.Dictionary []}
-  in
-    let pdf, pageroot = Pdfpage.add_pagetree (many page args.createpdf_pages) (Pdf.empty ()) in
-      Pdfpage.add_root pageroot [] pdf
-
 let write_json output pdf =
   match output with
   | NoOutputSpecified ->
@@ -3317,7 +3152,7 @@ let go () =
                       let pdfs =
                         if args.merge_add_bookmarks then
                           map2
-                            (fun filename pdf -> add_bookmark_title filename args.merge_add_bookmarks_use_titles pdf)
+                            (fun filename pdf -> Cpdf.add_bookmark_title filename args.merge_add_bookmarks_use_titles pdf)
                             (map (function InFile s -> s | StdIn -> "" | AlreadyInMemory _ -> "") names)
                             pdfs
                         else
@@ -3348,7 +3183,7 @@ let go () =
       begin match args.inputs, args.out with
       | _::_, _ ->
          let pdf = get_single_pdf (Some RemoveUnusedResources) false in
-           let outpdf = remove_unused_resources pdf in
+           let outpdf = Cpdf.remove_unused_resources pdf in
              write_pdf true outpdf
       | _ -> error "RemoveUnusedResources: bad command line"
       end
@@ -3523,7 +3358,7 @@ let go () =
                 | _ -> error "Copy box: no tobox or no frombox specified"
                 end
               in
-                let pdf = copy_box f t args.mediabox_if_missing pdf range in
+                let pdf = Cpdf.copy_box f t args.mediabox_if_missing pdf range in
                   write_pdf false pdf
       | _ -> error "Copy Box: bad command line"
       end
@@ -3866,8 +3701,8 @@ let go () =
   | Some DumpAttachedFiles ->
       let pdf = get_single_pdf args.op false in
         begin match args.out with
-        | NoOutputSpecified -> dump_attached_files pdf ""
-        | File n -> dump_attached_files pdf n
+        | NoOutputSpecified -> Cpdf.dump_attached_files pdf ""
+        | File n -> Cpdf.dump_attached_files pdf n
         | Stdout -> error "Can't dump attachments to stdout"
         end
   | Some RemoveAttachedFiles ->
@@ -4109,7 +3944,7 @@ let go () =
         Cpdf.print_dict_entry pdf key
   | Some ListSpotColours ->
       let pdf = get_single_pdf args.op false in
-        list_spot_colours pdf
+        Cpdf.list_spot_colours pdf
   | Some RemoveClipping ->
       let pdf = get_single_pdf args.op false in
         let range = parse_pagespec_allow_empty pdf (get_pagespec ()) in
@@ -4131,9 +3966,9 @@ let go () =
         Cpdffont.embed_missing_fonts args.path_to_ghostscript args.gs_quiet fi fo
   | Some (BookmarksOpenToLevel n) ->
       let pdf = get_single_pdf args.op false in
-        write_pdf false (bookmarks_open_to_level n pdf)
+        write_pdf false (Cpdf.bookmarks_open_to_level n pdf)
   | Some CreatePDF ->
-      let pdf = create_pdf args.createpdf_pages args.createpdf_pagesize in
+      let pdf = Cpdf.create_pdf args.createpdf_pages args.createpdf_pagesize in
         write_pdf false pdf
   | Some RemoveAllText ->
       let pdf = get_single_pdf args.op false in