open Pdfutil open Cpdferror type color = Grey of float | RGB of float * float * float | CYMK of float * float * float * float (* \section{Superimpose text, page numbers etc.} *) (* Process UTF8 text to /WinAnsiEncoding string (for standard 14) or whatever is in the font (for existing fonts). *) let charcodes_of_utf8 font s = let extractor = Pdftext.charcode_extractor_of_font_real ~debug:false font in let codepoints = Pdftext.codepoints_of_utf8 s in let charcodes = option_map (fun codepoint -> match extractor codepoint with | Some cc -> Some cc | None -> Printf.eprintf "Warning: character not found in font for unicode codepoint 0x%X\n" codepoint; None) codepoints in implode (map char_of_int charcodes) (* Process codepoints back to UTF8, assuming it came from UTF8 to start with *) let utf8_of_winansi s = let text_extractor = Pdftext.text_extractor_of_font_real (Pdftext.StandardFont (Pdftext.TimesRoman, Pdftext.WinAnsiEncoding)) in let codepoints = Pdftext.codepoints_of_text text_extractor s in Pdftext.utf8_of_codepoints codepoints (* Get the width of some text in the given font *) let width_of_text font text = match font with | Pdftext.SimpleFont {Pdftext.fontmetrics = Some fontmetrics} -> begin try fold_left ( +. ) 0. (map (fun c -> fontmetrics.(int_of_char c)) (explode text)) with _ -> 0. end | _ -> 0. type ops_metrics = {metrics_text : string; metrics_x : float; metrics_y : float; metrics_rot : float} let ops_metrics : ops_metrics list ref = ref [] let ops_baseline_adjustment = ref 0. let metrics_howmany () = length !ops_metrics let metrics_text n = utf8_of_winansi (select n !ops_metrics).metrics_text let metrics_x n = (select n !ops_metrics).metrics_x let metrics_y n = (select n !ops_metrics).metrics_y let metrics_rot n = (select n !ops_metrics).metrics_rot let metrics_baseline_adjustment () = !ops_baseline_adjustment let colour_op = function | RGB (r, g, b) -> Pdfops.Op_rg (r, g, b) | Grey g -> Pdfops.Op_g g | CYMK (c, y, m, k) -> Pdfops.Op_k (c, y, m, k) let colour_op_stroke = function | RGB (r, g, b) -> Pdfops.Op_RG (r, g, b) | Grey g -> Pdfops.Op_G g | CYMK (c, y, m, k) -> Pdfops.Op_K (c, y, m, k) let ops longest_w metrics x y rotate hoffset voffset outline linewidth unique_fontname unique_extgstatename colour fontsize text = if metrics then ops_metrics := {metrics_text = text; metrics_x = x -. hoffset; metrics_y = y -. voffset; metrics_rot = rotate} ::!ops_metrics; [Pdfops.Op_q; Pdfops.Op_BMC "/CPDFSTAMP"; Pdfops.Op_cm (Pdftransform.matrix_of_transform [Pdftransform.Translate (x -. hoffset, y -. voffset); Pdftransform.Rotate ((0., 0.), rotate)]); Pdfops.Op_BT; ] @ (if outline then [Pdfops.Op_w linewidth; Pdfops.Op_Tr 1] else [Pdfops.Op_Tr 0]) @ [colour_op colour; colour_op_stroke colour] @ (match unique_extgstatename with None -> [] | Some n -> [Pdfops.Op_gs n]) @ [Pdfops.Op_Tf (unique_fontname, fontsize); Pdfops.Op_Tj text; Pdfops.Op_ET; Pdfops.Op_EMC; Pdfops.Op_Q] type justification = LeftJustify | CentreJustify | RightJustify (* Find the h-offset for justification based on the longest width, the current width, the justification and the position. *) let find_justification_offsets longest_w w position j = let open Cpdfposition in match j with | LeftJustify -> begin match position with | TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> 0. | Top _ | PosCentre _ | Bottom _ | Centre -> (longest_w -. w) /. 2. | TopRight _ | BottomRight _ | PosRight _ | Right _ -> longest_w -. w | Diagonal -> 0. | ReverseDiagonal -> 0. end | RightJustify -> begin match position with | TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> ~-.(longest_w -. w) | Top _ | PosCentre _ | Bottom _ | Centre -> ~-.((longest_w -. w) /. 2.) | TopRight _ | BottomRight _ | PosRight _ | Right _ -> 0. | Diagonal -> 0. | ReverseDiagonal -> 0. end | CentreJustify -> begin match position with | TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> ~-.((longest_w -. w) /. 2.) | Top _ | PosCentre _ | Bottom _ | Centre -> 0. | TopRight _ | BottomRight _ | PosRight _ | Right _ -> (longest_w -. w) /. 2. | Diagonal -> 0. | ReverseDiagonal -> 0. end (* Lex an integer from the table *) let extract_num header s = match Pdfgenlex.lex_string (Hashtbl.find header s) with [Pdfgenlex.LexInt i] -> Pdf.Integer i | [Pdfgenlex.LexReal f] -> Pdf.Real f | _ -> raise (Failure ("extract_num: " ^ s)) let extract_fontbbox header s = let num = function Pdfgenlex.LexInt i -> Pdf.Integer i | Pdfgenlex.LexReal f -> Pdf.Real f | _ -> raise (Failure "extract_fontbbox") in match Pdfgenlex.lex_string (Hashtbl.find header s) with [a; b; c; d] -> [num a; num b; num c; num d] | _ -> raise (Failure "extract_fontbbox") let remove_slash s = match explode s with '/'::x -> implode x | _ -> raise (Failure "remove_slash") let extract_widths chars_and_widths = let win_to_name = map (fun (x, y) -> (y, x)) Pdfglyphlist.name_to_win in map (fun x -> try let name = List.assoc x win_to_name in let width = List.assoc (remove_slash name) chars_and_widths in width with _ -> 0) (ilist 0 255) let make_font embed fontname = let font = unopt (Pdftext.standard_font_of_name ("/" ^ fontname)) in let header, width_data, _, chars_and_widths = Pdfstandard14.afm_data font in let widths = extract_widths (list_of_hashtbl chars_and_widths) in let flags = Pdfstandard14.flags_of_standard_font font in let fontbbox = extract_fontbbox header "FontBBox" in let italicangle = extract_num header "ItalicAngle" in let ascent = try extract_num header "Ascender" with _ -> Pdf.Integer 0 in let descent = try extract_num header "Descender" with _ -> Pdf.Integer 0 in let capheight = try extract_num header "CapHeight" with _ -> Pdf.Integer 0 in let stemv = Pdfstandard14.stemv_of_standard_font font in let fontdescriptor = Pdf.Dictionary [("/Type", Pdf.Name "/FontDescriptor"); ("/FontName", Pdf.Name ("/" ^ fontname)); ("/Flags", Pdf.Integer flags); ("/FontBBox", Pdf.Array fontbbox); ("/ItalicAngle", italicangle); ("/Ascent", ascent); ("/Descent", descent); ("/CapHeight", capheight); ("/StemV", Pdf.Integer stemv)] in (* With -no-embed-font, we use the standard encoding, and just the * minimal stuff. Without -no-embed-font, we switch to WinAnsiEncoding, * and fill out everything except the font file instead *) if embed then Pdf.Dictionary [("/Type", Pdf.Name "/Font"); ("/Subtype", Pdf.Name "/Type1"); ("/BaseFont", Pdf.Name ("/" ^ fontname)); ("/Encoding", Pdf.Name "/WinAnsiEncoding"); ("/FirstChar", Pdf.Integer 0); ("/LastChar", Pdf.Integer 255); ("/Widths", Pdf.Array (map (fun x -> Pdf.Integer x) widths)); ("/FontDescriptor", fontdescriptor)] else Pdf.Dictionary [("/Type", Pdf.Name "/Font"); ("/Subtype", Pdf.Name "/Type1"); ("/Encoding", Pdf.Name "/WinAnsiEncoding"); ("/BaseFont", Pdf.Name ("/" ^ fontname))] let extract_page_text only_fontsize pdf _ page = let text_extractor = ref None in let right_font_size = ref false in fold_left ( ^ ) "" (map (function | Pdfops.Op_Tf (fontname, fontsize) -> right_font_size := begin match only_fontsize with Some x -> x = fontsize | _ -> false end; let fontdict = match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with | None -> raise (Pdf.PDFError "Missing /Font in text extraction") | Some d -> match Pdf.lookup_direct pdf fontname d with | None -> raise (Pdf.PDFError "Missing font in text extraction") | Some d -> d in text_extractor := Some (Pdftext.text_extractor_of_font pdf fontdict); "" | Pdfops.Op_Tj text when !text_extractor <> None -> if not !right_font_size then "" else Pdftext.utf8_of_codepoints (Pdftext.codepoints_of_text (unopt !text_extractor) text) | Pdfops.Op_TJ (Pdf.Array objs) when !text_extractor <> None -> if not !right_font_size then "" else fold_left ( ^ ) "" (option_map (function | Pdf.String text -> Some (Pdftext.utf8_of_codepoints (Pdftext.codepoints_of_text (unopt !text_extractor) text)) | _ -> None) objs) | _ -> "") (Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content)) (* For each page, extract all the ops with text in them, and concatenate it all together *) let extract_text extract_text_font_size pdf range = fold_left (fun x y -> x ^ (if x <> "" && y <> "" then "\n" else "") ^ y) "" (Cpdfpage.map_pages (extract_page_text extract_text_font_size pdf) pdf range) let rec process_text time text m = match m with | [] -> Cpdfstrftime.strftime ~time text | (s, r)::t -> process_text time (string_replace_all_lazy s r text) t (* Return page label at pdf page num, or page number in arabic if no label *) let pagelabel pdf num = Pdfpagelabels.pagelabeltext_of_pagenumber num (Pdfpagelabels.complete (Pdfpagelabels.read pdf)) let addtext metrics lines linewidth outline fast colour fontname embed bates batespad fontsize font underneath position hoffset voffset text pages orientation cropbox opacity justification filename extract_text_font_size shift pdf = let time = Cpdfstrftime.current_time () in let endpage = Pdfpage.endpage pdf in let replace_pairs pdf filename bates batespad num page = [ "%PageDiv2", (fun () -> string_of_int ((num + 1) / 2)); "%Page", (fun () -> string_of_int num); "%Roman", (fun () -> roman_upper num); "%roman", (fun () -> roman_lower num); "%filename", (fun () -> filename); "%Label", (fun () -> pagelabel pdf num); "%EndPage", (fun () -> string_of_int endpage); "%EndLabel", (fun () -> pagelabel pdf endpage); "%ExtractedText", (fun () -> extract_page_text extract_text_font_size pdf num page); "%Bates", (fun () -> (let numstring = string_of_int (bates + num - 1) in match batespad with None -> numstring | Some w -> if String.length numstring >= w then numstring else implode (many '0' (w - String.length numstring)) ^ numstring))] in let shifts = Cpdfcoord.parse_coordinates pdf shift in let addtext_page num page = let shift_x, shift_y = List.nth shifts (num - 1) in let resources', unique_extgstatename = if opacity < 1.0 then let dict = match Pdf.lookup_direct pdf "/ExtGState" page.Pdfpage.resources with | Some d -> d | None -> Pdf.Dictionary [] in let unique_extgstatename = Pdf.unique_key "gs" dict in let dict' = Pdf.add_dict_entry dict unique_extgstatename (Pdf.Dictionary [("/ca", Pdf.Real opacity); ("/CA", Pdf.Real opacity)]) in Pdf.add_dict_entry page.Pdfpage.resources "/ExtGState" dict', Some unique_extgstatename else page.Pdfpage.resources, None in let fontdict = match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with | None -> Pdf.Dictionary [] | Some d -> d in let unique_fontname = Pdf.unique_key "F" fontdict in let ops = let text = process_text time text (replace_pairs pdf filename bates batespad num page) in let calc_textwidth text = match font with | Some f -> let rawwidth = Pdfstandard14.textwidth false (if embed then Pdftext.WinAnsiEncoding else Pdftext.StandardEncoding) f text in (float rawwidth *. fontsize) /. 1000. | None -> let font = match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with | Some fontdict -> begin match Pdf.lookup_direct pdf fontname fontdict with | Some font -> font | None -> (* For each item in the fontdict, follow its value and find the basename. If it matches, return that font *) let font = ref None in iter (fun (k, v) -> match Pdf.lookup_direct pdf "/BaseFont" v with | Some (Pdf.Name n) when n = fontname -> font := Some v | _ -> ()) (match fontdict with Pdf.Dictionary d -> d | _ -> []); match !font with Some f -> f | None -> failwith (Printf.sprintf "addtext: font %s not found" fontname) end | _ -> failwith "addtext: font not found for width" in let rawwidth = width_of_text (Pdftext.read_font pdf font) text in (rawwidth *. fontsize) /. 1000. in let expanded_lines = map (function text -> process_text time text (replace_pairs pdf filename bates batespad num page)) lines in let textwidth = calc_textwidth text and allwidths = map calc_textwidth expanded_lines in let longest_w = last (sort compare allwidths) in let joffset = find_justification_offsets longest_w textwidth position justification in let mediabox = if cropbox then match Pdf.lookup_direct pdf "/CropBox" page.Pdfpage.rest with | Some pdfobject -> Pdf.parse_rectangle (Pdf.direct pdf pdfobject) | None -> Pdf.parse_rectangle page.Pdfpage.mediabox else Pdf.parse_rectangle page.Pdfpage.mediabox in let x, y, rotate = Cpdfposition.calculate_position false textwidth mediabox orientation position in let hoffset, voffset = if position = Diagonal || position = ReverseDiagonal then -. (cos ((pi /. 2.) -. rotate) *. voffset), sin ((pi /. 2.) -. rotate) *. voffset else hoffset, voffset in match font with | Some f -> ops longest_w metrics (x +. shift_x) (y +. shift_y) rotate (hoffset +. joffset) voffset outline linewidth unique_fontname unique_extgstatename colour fontsize text | None -> ops longest_w metrics (x +. shift_x) (y +. shift_y) rotate (hoffset +. joffset) voffset outline linewidth fontname None colour fontsize text in let newresources = match font with | Some _ -> let newfontdict = Pdf.add_dict_entry fontdict unique_fontname (make_font embed fontname) in Pdf.add_dict_entry resources' "/Font" newfontdict | None -> page.Pdfpage.resources in let page = {page with Pdfpage.resources = newresources} in if underneath then Pdfpage.prepend_operators pdf ops ~fast:fast page else Pdfpage.postpend_operators pdf ops ~fast:fast page in if metrics then (ignore (Cpdfpage.iter_pages (fun a b -> ignore (addtext_page a b)) pdf pages); pdf) else Cpdfpage.process_pages (Cpdfutil.ppstub addtext_page) pdf pages (* Prev is a list of lists of characters *) let split_at_newline t = let rec split_at_newline_inner prev = function | [] -> rev (map implode (map rev prev)) | '\\'::'\\'::'n'::t -> split_at_newline_inner (('n'::'\\'::'\\'::hd prev)::tl prev) t | '\\'::'n'::t -> split_at_newline_inner ([]::prev) t | h::t -> split_at_newline_inner ((h::hd prev)::tl prev) t in split_at_newline_inner [[]] (explode t) let rec unescape_chars prev = function | [] -> rev prev | '\\'::('0'..'7' as a)::('0'..'7' as b)::('0'..'7' as c)::t -> let chr = char_of_int (int_of_string ("0o" ^ implode [a;b;c])) in unescape_chars (chr::prev) t | '\\'::'\\'::t -> unescape_chars ('\\'::prev) t | '\\'::c::t when c <> 'n' -> unescape_chars (c::prev) t | h::t -> unescape_chars (h::prev) t let unescape_string s = implode (unescape_chars [] (explode s)) let addtexts metrics linewidth outline fast fontname (font : Pdftext.standard_font option) embed bates batespad colour position linespacing fontsize underneath text pages orientation cropbox opacity justification midline topline filename extract_text_font_size shift ?(raw=false) pdf = if pages = [] then error "addtexts: empty page range" else (*flprint "addtexts:\n"; iter (Printf.printf "%C ") (explode text); flprint "\n"; Printf.printf "\nCpdf.addtexts: metrics = %b" metrics; flprint "\n";*) (*Printf.printf "linewidth = %f\n" linewidth; Printf.printf "outline = %b\n" outline; Printf.printf "fast = %b\n" fast; Printf.printf "fontname = %s\n" fontname; Printf.printf "winansi text = %s\n" text; Printf.printf "position = %s\n" (string_of_position position); Printf.printf "bates = %i\n" bates; Printf.printf "linespacing = %f\n" linespacing; Printf.printf "fontsize = %f\n" fontsize; Printf.printf "underneath = %b\n" underneath; Printf.printf "font = %s\n" begin match font with None -> "None" | Some x -> Pdftext.string_of_standard_font x end; Printf.printf "justification = %s\n" begin match justification with LeftJustify -> "left" | RightJustify -> "right" | CentreJustify -> "centre" end; Printf.printf "midline = %b\n" midline; begin match colour with r, g, b -> Printf.printf "%f, %f, %f\n" r g b end; Printf.printf "opacity = %f\n" opacity; flprint "\n"; Printf.printf "relative-to-cropbox = %b" cropbox; flprint "\n";*) ops_metrics := []; let realfontname = ref fontname in let fontpdfobj = match font with | Some f -> make_font embed (Pdftext.string_of_standard_font f) | None -> let firstpage = List.nth (Pdfpage.pages_of_pagetree pdf) (hd pages - 1) in match Pdf.lookup_direct pdf "/Font" firstpage.Pdfpage.resources with | Some fontdict -> begin match Pdf.lookup_direct pdf fontname fontdict with | Some font -> font | _ -> (* For each item in the fontdict, follow its value and find the basename. If it matches, return that font *) let font = ref None in iter (fun (k, v) -> match Pdf.lookup_direct pdf "/BaseFont" v with | Some (Pdf.Name n) when n = fontname -> font := Some v; realfontname := k | _ -> ()) (match fontdict with Pdf.Dictionary d -> d | _ -> []); match !font with Some f -> f | None -> failwith (Printf.sprintf "addtext: font %s not found" fontname) end | _ -> failwith "addtext: font dictionary not present" in let text = if raw then text else charcodes_of_utf8 (Pdftext.read_font pdf fontpdfobj) text in let lines = map unescape_string (split_at_newline text) in let pdf = ref pdf in let voffset = let open Cpdfposition in match position with | Bottom _ | BottomLeft _ | BottomRight _ -> ref (0. -. (linespacing *. fontsize *. (float (length lines) -. 1.))) | Left _ | Right _ -> (* Vertically align *) ref (0. -. (linespacing *. ((fontsize *. (float (length lines) -. 1.)) /. 2.))) | Diagonal | ReverseDiagonal -> (* Change so that the whole paragraph sits on the centre... *) ref (0. -. ((linespacing *. fontsize *. (float (length lines) -. 1.)) /. 2.)) | _ -> ref 0. in if midline then begin match font with | Some font -> let baseline_adjustment = (fontsize *. float (Pdfstandard14.baseline_adjustment font)) /. 1000. in ops_baseline_adjustment := baseline_adjustment; voffset := !voffset +. baseline_adjustment | _ -> ops_baseline_adjustment := 0. end else if topline then begin match font with | Some font -> let baseline_adjustment = (fontsize *. float (Pdfstandard14.baseline_adjustment font) *. 2.0) /. 1000. in ops_baseline_adjustment := baseline_adjustment; voffset := !voffset +. baseline_adjustment | _ -> ops_baseline_adjustment := 0. end else ops_baseline_adjustment := 0.; iter (fun line -> let voff, hoff = if orientation = Cpdfposition.Vertical then 0., -.(!voffset) else !voffset, 0. in pdf := addtext metrics lines linewidth outline fast colour !realfontname embed bates batespad fontsize font underneath position hoff voff line pages orientation cropbox opacity justification filename extract_text_font_size shift !pdf; voffset := !voffset +. (linespacing *. fontsize)) lines; ops_metrics := rev !ops_metrics; !pdf let removetext range pdf = (* Could fail on nesting, or other marked content inside our marked content.*) let rec remove_until_last_EMC level = function | [] -> [] | Pdfops.Op_BMC "/CPDFSTAMP"::more -> remove_until_last_EMC (level + 1) more | Pdfops.Op_EMC::more -> if level = 1 then more else remove_until_last_EMC (level - 1) more | _::more -> remove_until_last_EMC level more in let rec remove_stamps prev = function | [] -> rev prev | Pdfops.Op_BMC "/CPDFSTAMP"::more -> let rest = remove_until_last_EMC 1 more in remove_stamps prev rest | h::t -> remove_stamps (h::prev) t in let removetext_page _ page = {page with Pdfpage.content = let ops = Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content in [Pdfops.stream_of_ops (remove_stamps [] ops)]} in Cpdfpage.process_pages (Cpdfutil.ppstub removetext_page) pdf range let addrectangle fast (w, h) colour outline linewidth opacity position relative_to_cropbox underneath range pdf = let addrectangle_page _ page = let resources', unique_extgstatename = if opacity < 1.0 then let dict = match Pdf.lookup_direct pdf "/ExtGState" page.Pdfpage.resources with | Some d -> d | None -> Pdf.Dictionary [] in let unique_extgstatename = Pdf.unique_key "gs" dict in let dict' = Pdf.add_dict_entry dict unique_extgstatename (Pdf.Dictionary [("/ca", Pdf.Real opacity); ("/CA", Pdf.Real opacity)]) in Pdf.add_dict_entry page.Pdfpage.resources "/ExtGState" dict', Some unique_extgstatename else page.Pdfpage.resources, None in let mediabox = if relative_to_cropbox then match Pdf.lookup_direct pdf "/CropBox" page.Pdfpage.rest with | Some pdfobject -> Pdf.parse_rectangle (Pdf.direct pdf pdfobject) | None -> Pdf.parse_rectangle page.Pdfpage.mediabox else Pdf.parse_rectangle page.Pdfpage.mediabox in let x, y, _ = Cpdfposition.calculate_position false w mediabox Cpdfposition.Horizontal position in let x, y = match position with Cpdfposition.Top _ | Cpdfposition.TopLeft _ | Cpdfposition.TopRight _ -> (x, y -. h) | Cpdfposition.Centre | Cpdfposition.PosCentre _ -> (x, y -. (h /. 2.)) | _ -> (x, y) in let ops = [ Pdfops.Op_q; Pdfops.Op_BMC "/CPDFSTAMP"; colour_op colour; colour_op_stroke colour; ] @ (if outline then [Pdfops.Op_w linewidth] else []) @ (match unique_extgstatename with None -> [] | Some n -> [Pdfops.Op_gs n]) @ [ Pdfops.Op_re (x, y, w, h); (if outline then Pdfops.Op_s else Pdfops.Op_f); Pdfops.Op_EMC; Pdfops.Op_Q ] in let page = {page with Pdfpage.resources = resources'} in if underneath then Pdfpage.prepend_operators pdf ops ~fast:fast page else Pdfpage.postpend_operators pdf ops ~fast:fast page in Cpdfpage.process_pages (Cpdfutil.ppstub addrectangle_page) pdf range open Pdfutil let rec remove_all_text_ops pdf resources content = let is_textop = function Pdfops.Op_Tj _ | Pdfops.Op_' _ | Pdfops.Op_'' _ | Pdfops.Op_TJ _ -> true | _ -> false in let content' = let ops = Pdfops.parse_operators pdf resources content in Pdfops.stream_of_ops (option_map (function x -> if is_textop x then None else Some x) ops) in [content'] let remove_all_text_page pdf p = let resources = p.Pdfpage.resources in let content = p.Pdfpage.content in Cpdfutil.process_xobjects pdf p remove_all_text_ops; {p with Pdfpage.content = remove_all_text_ops pdf resources content}, pdf let remove_all_text range pdf = let pages = Pdfpage.pages_of_pagetree pdf in let pagenums = indx pages in let pdf = ref pdf in let pages' = ref [] in iter2 (fun p pagenum -> let p', pdf' = if mem pagenum range then remove_all_text_page !pdf p else p, !pdf in pdf := pdf'; pages' =| p') pages pagenums; Pdfpage.change_pages true !pdf (rev !pages')