718 lines
29 KiB
OCaml
718 lines
29 KiB
OCaml
open Pdfutil
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open Cpdferror
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type color =
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Grey of float
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| RGB of float * float * float
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| CYMK of float * float * float * float
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(* Superimpose text, page numbers etc. *)
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(* Process UTF8 text to /WinAnsiEncoding string (for standard 14) or whatever
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is in the font (for existing fonts). *)
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let charcodes_of_utf8 font s =
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let extractor = Pdftext.charcode_extractor_of_font_real ~debug:false font in
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let codepoints = Pdftext.codepoints_of_utf8 s in
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let charcodes =
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option_map
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(fun codepoint ->
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match extractor codepoint with
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| Some cc -> Some cc
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| None -> Printf.eprintf "Warning: character not found in font for unicode codepoint 0x%X\n" codepoint; None)
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codepoints
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in
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implode (map char_of_int charcodes)
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(* Process codepoints back to UTF8, assuming it came from UTF8 to start with *)
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let utf8_of_winansi s =
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let text_extractor =
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Pdftext.text_extractor_of_font_real
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(Pdftext.StandardFont (Pdftext.TimesRoman, Pdftext.WinAnsiEncoding))
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in
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let codepoints = Pdftext.codepoints_of_text text_extractor s in
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Pdftext.utf8_of_codepoints codepoints
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(* Get the width of some text in the given font *)
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let width_of_text font text =
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match font with
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| Pdftext.SimpleFont {Pdftext.fontmetrics = Some fontmetrics} ->
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begin try
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fold_left ( +. ) 0. (map (fun c -> fontmetrics.(int_of_char c)) (explode text))
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with
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_ -> 0.
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end
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| _ -> 0.
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let colour_op = function
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| RGB (r, g, b) -> Pdfops.Op_rg (r, g, b)
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| Grey g -> Pdfops.Op_g g
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| CYMK (c, y, m, k) -> Pdfops.Op_k (c, y, m, k)
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let colour_op_stroke = function
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| RGB (r, g, b) -> Pdfops.Op_RG (r, g, b)
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| Grey g -> Pdfops.Op_G g
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| CYMK (c, y, m, k) -> Pdfops.Op_K (c, y, m, k)
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let ops longest_w x y rotate hoffset voffset outline linewidth unique_fontname unique_extgstatename colour fontsize text =
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[Pdfops.Op_q;
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Pdfops.Op_BMC "/CPDFSTAMP";
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Pdfops.Op_cm
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(Pdftransform.matrix_of_transform
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[Pdftransform.Translate (x -. hoffset, y -. voffset);
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Pdftransform.Rotate ((0., 0.), rotate)]);
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Pdfops.Op_BT;
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] @
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(if outline then [Pdfops.Op_w linewidth; Pdfops.Op_Tr 1] else [Pdfops.Op_Tr 0]) @
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[colour_op colour; colour_op_stroke colour]
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@
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(match unique_extgstatename with None -> [] | Some n -> [Pdfops.Op_gs n])
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@
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[Pdfops.Op_Tf (unique_fontname, fontsize);
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Pdfops.Op_Tj text;
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Pdfops.Op_ET;
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Pdfops.Op_EMC;
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Pdfops.Op_Q]
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type justification = LeftJustify | CentreJustify | RightJustify
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(* Find the h-offset for justification based on the longest width, the current
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width, the justification and the position. *)
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let find_justification_offsets longest_w w position j =
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let open Cpdfposition in
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match j with
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| LeftJustify ->
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begin match position with
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| TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> 0.
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| Top _ | PosCentre _ | Bottom _ | Centre -> (longest_w -. w) /. 2.
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| TopRight _ | BottomRight _ | PosRight _ | Right _ -> longest_w -. w
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| Diagonal -> 0.
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| ReverseDiagonal -> 0.
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end
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| RightJustify ->
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begin match position with
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| TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> ~-.(longest_w -. w)
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| Top _ | PosCentre _ | Bottom _ | Centre -> ~-.((longest_w -. w) /. 2.)
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| TopRight _ | BottomRight _ | PosRight _ | Right _ -> 0.
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| Diagonal -> 0.
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| ReverseDiagonal -> 0.
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end
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| CentreJustify ->
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begin match position with
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| TopLeft _ | Left _ | PosLeft _ | BottomLeft _ -> ~-.((longest_w -. w) /. 2.)
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| Top _ | PosCentre _ | Bottom _ | Centre -> 0.
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| TopRight _ | BottomRight _ | PosRight _ | Right _ -> (longest_w -. w) /. 2.
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| Diagonal -> 0.
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| ReverseDiagonal -> 0.
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end
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(* Lex an integer from the table *)
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let extract_num header s =
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match Pdfgenlex.lex_string (Hashtbl.find header s) with
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[Pdfgenlex.LexInt i] -> Pdf.Integer i
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| [Pdfgenlex.LexReal f] -> Pdf.Real f
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| _ -> raise (Failure ("extract_num: " ^ s))
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let extract_fontbbox header s =
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let num = function
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Pdfgenlex.LexInt i -> Pdf.Integer i
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| Pdfgenlex.LexReal f -> Pdf.Real f
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| _ -> raise (Failure "extract_fontbbox")
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in
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match Pdfgenlex.lex_string (Hashtbl.find header s) with
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[a; b; c; d] -> [num a; num b; num c; num d]
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| _ -> raise (Failure "extract_fontbbox")
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let remove_slash s =
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match explode s with
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'/'::x -> implode x
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| _ -> raise (Failure "remove_slash")
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let extract_widths chars_and_widths =
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let win_to_name = map (fun (x, y) -> (y, x)) Pdfglyphlist.name_to_win in
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map
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(fun x ->
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try
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let name = List.assoc x win_to_name in
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let width = List.assoc (remove_slash name) chars_and_widths in
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width
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with
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_ -> 0)
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(ilist 0 255)
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(* For finding the height for URL links, we try to find the Cap Height for the
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font. For now, this will only work for built-in fonts. We fall back to using
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the font size alone if we cannot get the cap height. *)
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let cap_height fontname =
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try
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let font = unopt (Pdftext.standard_font_of_name ("/" ^ fontname)) in
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let header, _, _, _ = Pdfstandard14.afm_data font in
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let capheight = try extract_num header "CapHeight" with _ -> Pdf.Integer 0 in
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Some (match capheight with Pdf.Integer i -> float_of_int i | Pdf.Real r -> r | _ -> 0.)
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with
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_ -> None
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let make_font embed fontname =
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let font = unopt (Pdftext.standard_font_of_name ("/" ^ fontname)) in
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let header, width_data, _, chars_and_widths = Pdfstandard14.afm_data font in
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let widths = extract_widths (list_of_hashtbl chars_and_widths) in
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let flags = Pdfstandard14.flags_of_standard_font font in
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let fontbbox = extract_fontbbox header "FontBBox" in
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let italicangle = extract_num header "ItalicAngle" in
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let ascent = try extract_num header "Ascender" with _ -> Pdf.Integer 0 in
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let descent = try extract_num header "Descender" with _ -> Pdf.Integer 0 in
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let capheight = try extract_num header "CapHeight" with _ -> Pdf.Integer 0 in
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let stemv = Pdfstandard14.stemv_of_standard_font font in
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let fontdescriptor =
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Pdf.Dictionary
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[("/Type", Pdf.Name "/FontDescriptor");
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("/FontName", Pdf.Name ("/" ^ fontname));
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("/Flags", Pdf.Integer flags);
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("/FontBBox", Pdf.Array fontbbox);
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("/ItalicAngle", italicangle);
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("/Ascent", ascent);
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("/Descent", descent);
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("/CapHeight", capheight);
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("/StemV", Pdf.Integer stemv)]
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in
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(* With -no-embed-font, we use the standard encoding, and just the
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* minimal stuff. Without -no-embed-font, we switch to WinAnsiEncoding,
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* and fill out everything except the font file instead *)
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if embed then
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Pdf.Dictionary
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[("/Type", Pdf.Name "/Font");
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("/Subtype", Pdf.Name "/Type1");
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("/BaseFont", Pdf.Name ("/" ^ fontname));
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("/Encoding", Pdf.Name "/WinAnsiEncoding");
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("/FirstChar", Pdf.Integer 0);
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("/LastChar", Pdf.Integer 255);
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("/Widths", Pdf.Array (map (fun x -> Pdf.Integer x) widths));
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("/FontDescriptor", fontdescriptor)]
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else
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Pdf.Dictionary
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[("/Type", Pdf.Name "/Font");
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("/Subtype", Pdf.Name "/Type1");
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("/Encoding", Pdf.Name "/WinAnsiEncoding");
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("/BaseFont", Pdf.Name ("/" ^ fontname))]
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let extract_page_text only_fontsize pdf _ page =
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let text_extractor = ref None in
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let right_font_size = ref false in
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fold_left ( ^ ) ""
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(map
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(function
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| Pdfops.Op_Tf (fontname, fontsize) ->
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right_font_size :=
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begin match only_fontsize with
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Some x -> x = fontsize
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| _ -> false
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end;
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let fontdict =
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match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with
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| None -> raise (Pdf.PDFError "Missing /Font in text extraction")
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| Some d ->
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match Pdf.lookup_direct pdf fontname d with
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| None -> raise (Pdf.PDFError "Missing font in text extraction")
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| Some d -> d
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in
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text_extractor := Some (Pdftext.text_extractor_of_font pdf fontdict);
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""
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| Pdfops.Op_Tj text when !text_extractor <> None ->
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if not !right_font_size then
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""
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else
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Pdftext.utf8_of_codepoints
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(Pdftext.codepoints_of_text (unopt !text_extractor) text)
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| Pdfops.Op_TJ (Pdf.Array objs) when !text_extractor <> None ->
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if not !right_font_size then
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""
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else
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fold_left ( ^ ) ""
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(option_map
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(function
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| Pdf.String text ->
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Some
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(Pdftext.utf8_of_codepoints
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(Pdftext.codepoints_of_text (unopt !text_extractor) text))
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| _ -> None)
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objs)
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| _ -> "")
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(Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content))
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(* For each page, extract all the ops with text in them, and concatenate it all together *)
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let extract_text extract_text_font_size pdf range =
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fold_left (fun x y -> x ^ (if x <> "" && y <> "" then "\n" else "") ^ y) ""
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(Cpdfpage.map_pages (extract_page_text extract_text_font_size pdf) pdf range)
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let rec process_text time text m =
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match m with
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| [] -> Cpdfstrftime.strftime ~time text
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| (s, r)::t -> process_text time (string_replace_all_lazy s r text) t
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(* Find any %URL, sub in the text and return the new text together with a list
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of ordered (line num, URL, startpos, endpos) data.
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This will be used after any other %Specials have been processed, so that the
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positions do not change. *)
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(* text|url]abc -> text, url, abc *)
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let extract_url line =
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let text, rest = cleavewhile (neq '|') line in
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if rest = [] then error "bad URL syntax in text" else
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let url, rest = cleavewhile (neq ']') (tl rest) in
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if rest = [] then error "bad URL syntax in text" else
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(text, url, tl rest)
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(* multiple %URL[a|b] *)
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let get_urls_line line =
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let line = explode line in
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let urls = ref [] in
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let pos = ref 0 in
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let outline = ref [] in
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let rec loop = function
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| '%'::'U'::'R'::'L'::'['::t ->
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let text, url, rest = extract_url t in
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outline := rev text @ !outline;
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urls := (implode url, !pos, !pos + length text)::!urls;
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pos += length text;
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loop rest
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| h::t ->
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outline := h::!outline;
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pos += 1;
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loop t
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| [] -> ()
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in
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loop line;
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(implode (rev !outline), rev !urls)
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(* Return page label at pdf page num, or page number in arabic if no label *)
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let pagelabel pdf num =
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Pdfpagelabels.pagelabeltext_of_pagenumber
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num
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(Pdfpagelabels.complete (Pdfpagelabels.read pdf))
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let addtext
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lines linewidth outline fast colour fontname embed bates batespad fontsize (font : Pdftext.font option)
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fontpdfobj underneath position hoffset voffset text pages orientation cropbox opacity
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justification filename extract_text_font_size shift pdf
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=
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let time = Cpdfstrftime.current_time () in
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let endpage = Pdfpage.endpage pdf in
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let replace_pairs pdf filename bates batespad num page =
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[
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"%PageDiv2", (fun () -> string_of_int ((num + 1) / 2));
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"%Page", (fun () -> string_of_int num);
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"%Roman", (fun () -> roman_upper num);
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"%roman", (fun () -> roman_lower num);
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"%filename", (fun () -> filename);
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"%Label", (fun () -> pagelabel pdf num);
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"%EndPage", (fun () -> string_of_int endpage);
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"%EndLabel", (fun () -> pagelabel pdf endpage);
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"%ExtractedText", (fun () -> extract_page_text extract_text_font_size pdf num page);
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"%Bates",
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(fun () ->
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(let numstring = string_of_int (bates + num - 1) in
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match batespad with
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None -> numstring
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| Some w ->
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if String.length numstring >= w
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then numstring
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else implode (many '0' (w - String.length numstring)) ^ numstring))]
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in
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let shifts = Cpdfcoord.parse_coordinates pdf shift in
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let addtext_page num page =
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let shift_x, shift_y = List.nth shifts (num - 1) in
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let resources', unique_extgstatename =
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if opacity < 1.0 then
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let dict =
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match Pdf.lookup_direct pdf "/ExtGState" page.Pdfpage.resources with
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| Some d -> d
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| None -> Pdf.Dictionary []
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in
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let unique_extgstatename = Pdf.unique_key "gs" dict in
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let dict' =
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Pdf.add_dict_entry dict unique_extgstatename
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(Pdf.Dictionary [("/ca", Pdf.Real opacity); ("/CA", Pdf.Real opacity)])
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in
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Pdf.add_dict_entry page.Pdfpage.resources "/ExtGState" dict', Some unique_extgstatename
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else
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page.Pdfpage.resources, None
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in
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let fontdict =
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match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with
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| None -> Pdf.Dictionary []
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| Some d -> d
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in
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let calc_textwidth text =
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match font with
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| Some (Pdftext.StandardFont (f, _)) ->
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let rawwidth =
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Pdfstandard14.textwidth
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false
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(if embed then Pdftext.WinAnsiEncoding else Pdftext.StandardEncoding)
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f
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text
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in
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(float rawwidth *. fontsize) /. 1000.
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| Some font ->
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let rawwidth = width_of_text font text in
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(rawwidth *. fontsize) /. 1000.
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| None ->
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let font =
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match Pdf.lookup_direct pdf "/Font" page.Pdfpage.resources with
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| Some fontdict ->
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begin match Pdf.lookup_direct pdf fontname fontdict with
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| Some font -> font
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| None ->
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(* For each item in the fontdict, follow its value and find the basename. If it matches, return that font *)
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let font = ref None in
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iter
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(fun (k, v) ->
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match Pdf.lookup_direct pdf "/BaseFont" v with
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| Some (Pdf.Name n) when n = fontname -> font := Some v
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| _ -> ())
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(match fontdict with Pdf.Dictionary d -> d | _ -> []);
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match !font with Some f -> f | None -> failwith (Printf.sprintf "addtext: font %s not found" fontname)
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end
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| _ -> failwith "addtext: font not found for width"
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in
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let rawwidth = width_of_text (Pdftext.read_font pdf font) text in
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(rawwidth *. fontsize) /. 1000.
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in
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let unique_fontname = Pdf.unique_key "F" fontdict in
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let ops, urls, x, y, hoffset, voffset, text, joffset =
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let text = process_text time text (replace_pairs pdf filename bates batespad num page) in
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let text, urls = get_urls_line text in
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let expanded_lines =
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map
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(function text ->
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process_text time text (replace_pairs pdf filename bates batespad num page))
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lines
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in
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let expanded_lines = (* process URLs for justification too *)
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map (fun line -> fst (get_urls_line line)) expanded_lines
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in
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let textwidth = calc_textwidth text
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and allwidths = map calc_textwidth expanded_lines in
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let longest_w = last (sort compare allwidths) in
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let joffset = find_justification_offsets longest_w textwidth position justification in
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let mediabox =
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if cropbox then
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match Pdf.lookup_direct pdf "/CropBox" page.Pdfpage.rest with
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| Some pdfobject -> Pdf.parse_rectangle pdf (Pdf.direct pdf pdfobject)
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| None -> Pdf.parse_rectangle pdf page.Pdfpage.mediabox
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else
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Pdf.parse_rectangle pdf page.Pdfpage.mediabox
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in
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let x, y, rotate = Cpdfposition.calculate_position false textwidth mediabox orientation position in
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let hoffset, voffset =
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if position = Diagonal || position = ReverseDiagonal
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then -. (cos ((pi /. 2.) -. rotate) *. voffset), sin ((pi /. 2.) -. rotate) *. voffset
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else hoffset, voffset
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in
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match font with
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| Some f ->
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ops longest_w (x +. shift_x) (y +. shift_y) rotate (hoffset +. joffset) voffset outline linewidth
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unique_fontname unique_extgstatename colour fontsize text,
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urls, x, y, hoffset, voffset, text, joffset
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| None ->
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ops longest_w (x +. shift_x) (y +. shift_y) rotate (hoffset +. joffset) voffset outline linewidth
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fontname None colour fontsize text,
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urls, x, y, hoffset, voffset, text, joffset
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in
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let newresources =
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match font with
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| Some (Pdftext.StandardFont _) ->
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let newfontdict =
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Pdf.add_dict_entry fontdict unique_fontname (make_font embed fontname)
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in
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Pdf.add_dict_entry resources' "/Font" newfontdict
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| Some f ->
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let newfontdict =
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Pdf.add_dict_entry fontdict unique_fontname fontpdfobj
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in
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Pdf.add_dict_entry resources' "/Font" newfontdict
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| None -> page.Pdfpage.resources
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in
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(* Build annotations from URL data (get_urls and some sense of metrics) *)
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let annot (minx, miny, maxx, maxy) url =
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Pdf.Dictionary
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[("/Subtype", Pdf.Name "/Link");
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("/Rect", Pdf.Array [Pdf.Real minx; Pdf.Real miny; Pdf.Real maxx; Pdf.Real maxy]);
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("/BS", Pdf.Dictionary [("/W", Pdf.Integer 0)]);
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("/A", Pdf.Dictionary [("/URI", Pdf.String url);
|
|
("/Type", Pdf.Name "/Action");
|
|
("/S", Pdf.Name "/URI")])]
|
|
in
|
|
let annots =
|
|
let annot_coord text pos =
|
|
let before = take (explode text) pos in
|
|
calc_textwidth (implode before)
|
|
in
|
|
map (fun (url, s, e) ->
|
|
let sx = annot_coord text s in
|
|
let ex = annot_coord text e in
|
|
let x, y = x -. hoffset -. joffset, y -. voffset in
|
|
let height =
|
|
match cap_height fontname with
|
|
| Some c -> (c *. fontsize) /. 1000.
|
|
| None -> fontsize
|
|
in
|
|
Pdf.Indirect (Pdf.addobj pdf (annot (x +. sx, y, x +. ex, y +. height) url))) urls
|
|
in
|
|
let newrest =
|
|
if annots = [] then page.Pdfpage.rest else
|
|
let existing =
|
|
match Pdf.lookup_direct pdf "/Annots" page.Pdfpage.rest with
|
|
| Some (Pdf.Array a) -> a
|
|
| _ -> []
|
|
in
|
|
Pdf.add_dict_entry page.Pdfpage.rest "/Annots" (Pdf.Array (annots @ existing))
|
|
in
|
|
let page =
|
|
{page with
|
|
Pdfpage.resources = newresources;
|
|
Pdfpage.rest = newrest}
|
|
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 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 linewidth outline fast fontname (font : Pdftext.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
|
|
let realfontname = ref fontname in
|
|
let fontpdfobj =
|
|
match font with
|
|
| Some (StandardFont (f, _)) ->
|
|
make_font embed (Pdftext.string_of_standard_font f)
|
|
| Some f ->
|
|
Pdf.Indirect (Pdftext.write_font pdf 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
|
|
(* 19th May 2022. Reversed the phase order (split first, then get charcodes. This allows \n in custom fonts. *)
|
|
let lines = map unescape_string (split_at_newline text) in
|
|
let lines = map (fun text -> if raw then text else charcodes_of_utf8 (Pdftext.read_font pdf fontpdfobj) text) lines 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 (Pdftext.StandardFont (font, _)) ->
|
|
let baseline_adjustment =
|
|
(fontsize *. float (Pdfstandard14.baseline_adjustment font)) /. 1000.
|
|
in
|
|
voffset := !voffset +. baseline_adjustment
|
|
| _ -> ()
|
|
end
|
|
else
|
|
if topline then
|
|
begin match font with
|
|
| Some (Pdftext.StandardFont (font, _)) ->
|
|
let baseline_adjustment =
|
|
(fontsize *. float (Pdfstandard14.baseline_adjustment font) *. 2.0) /. 1000.
|
|
in
|
|
voffset := !voffset +. baseline_adjustment
|
|
| _ -> ()
|
|
end
|
|
else
|
|
iter
|
|
(fun line ->
|
|
let voff, hoff =
|
|
if orientation = Cpdfposition.Vertical then 0., -.(!voffset) else !voffset, 0.
|
|
in
|
|
pdf :=
|
|
addtext lines linewidth outline fast colour !realfontname
|
|
embed bates batespad fontsize font fontpdfobj underneath position hoff voff line
|
|
pages orientation cropbox opacity justification filename
|
|
extract_text_font_size shift
|
|
!pdf;
|
|
voffset := !voffset +. (linespacing *. fontsize))
|
|
lines;
|
|
!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 (Pdf.direct pdf pdfobject)
|
|
| None -> Pdf.parse_rectangle pdf page.Pdfpage.mediabox
|
|
else
|
|
Pdf.parse_rectangle pdf 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
|
|
|
|
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')
|