66 lines
2.1 KiB
OCaml
66 lines
2.1 KiB
OCaml
open Pdfutil
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let removetext range pdf =
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(* Could fail on nesting, or other marked content inside our marked content.*)
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let rec remove_until_last_EMC level = function
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| [] -> []
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| Pdfops.Op_BMC "/CPDFSTAMP"::more ->
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remove_until_last_EMC (level + 1) more
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| Pdfops.Op_EMC::more ->
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if level = 1
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then more
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else remove_until_last_EMC (level - 1) more
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| _::more ->
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remove_until_last_EMC level more
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in
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let rec remove_stamps prev = function
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| [] -> rev prev
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| Pdfops.Op_BMC "/CPDFSTAMP"::more ->
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let rest = remove_until_last_EMC 1 more in
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remove_stamps prev rest
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| h::t -> remove_stamps (h::prev) t
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in
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let removetext_page _ page =
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{page with
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Pdfpage.content =
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let ops = Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content in
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[Pdfops.stream_of_ops (remove_stamps [] ops)]}
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in
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Cpdfpage.process_pages (Pdfpage.ppstub removetext_page) pdf range
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let rec remove_all_text_ops pdf resources content =
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let is_textop = function
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Pdfops.Op_Tj _ | Pdfops.Op_' _ | Pdfops.Op_'' _ | Pdfops.Op_TJ _ -> true
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| _ -> false
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in
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let content' =
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let ops = Pdfops.parse_operators pdf resources content in
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Pdfops.stream_of_ops
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(option_map (function x -> if is_textop x then None else Some x) ops)
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in
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[content']
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let remove_all_text_page pdf p =
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let resources = p.Pdfpage.resources in
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let content = p.Pdfpage.content in
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Pdfpage.process_xobjects pdf p remove_all_text_ops;
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{p with Pdfpage.content = remove_all_text_ops pdf resources content}, pdf
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let remove_all_text range pdf =
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let pages = Pdfpage.pages_of_pagetree pdf in
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let pagenums = indx pages in
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let pdf = ref pdf in
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let pages' = ref [] in
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iter2
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(fun p pagenum ->
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let p', pdf' =
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if mem pagenum range
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then remove_all_text_page !pdf p
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else p, !pdf
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in
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pdf := pdf';
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pages' =| p')
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pages
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pagenums;
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Pdfpage.change_pages true !pdf (rev !pages')
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