fenix
/
cpdf-source
mirror of https://github.com/johnwhitington/cpdf-source.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Direct PNG output was misinformed

This commit is contained in:
John Whitington 2023-06-14 18:38:26 +01:00
parent 5f688481ea
commit 261f121040
1 changed files with 32 additions and 67 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

97
cpdfimage.ml
View File

@ -22,83 +22,48 @@ let pnm_to_channel_24 channel w h s =
done
done
(* FIXME do this all at once *)
let write_stream name stream =
let fh = open_out_bin name in
for x = 0 to bytes_size stream - 1 do
output_byte fh (bget stream x)
done;
Pdfio.bytes_to_output_channel fh stream;
close_out fh
(* Detect images we can write directly as PNGs, to avoid going through pnm2png or imagemagick.
This is when BPC = 8, colourspace = DeviceRGB or CalRGB, compression is /FlateDecode. *)
let write_image_png pdf resources name dict =
(*Printf.printf "%s\n" (Pdfwrite.string_of_pdf (Pdf.direct pdf dict));*)
match
Pdfimage.colspace pdf dict resources,
Pdfimage.bpc pdf dict,
Pdf.lookup_direct pdf "/Filter" dict
with
| (Pdfspace.DeviceRGB | Pdfspace.CalRGB _),
Some (Pdf.Integer 8),
Some (Pdf.Name "/FlateDecode" | Pdf.Array [Pdf.Name "/FlateDecode"]) ->
(*Printf.printf "Direct to png...\n";*)
Pdf.getstream (Pdf.direct pdf dict);
let ch = open_out_bin (name ^ ".png") in
let o = Pdfio.output_of_channel ch in
let width = match Pdf.lookup_direct pdf "/Width" dict with Some (Pdf.Integer x) -> x | _ -> raise Exit in
let height = match Pdf.lookup_direct pdf "/Height" dict with Some (Pdf.Integer x) -> x | _ -> raise Exit in
let idat = match Pdf.direct pdf dict with Pdf.Stream {contents = (_, Got bytes)} -> bytes | _ -> raise Exit in
(*Printf.printf "all ok...\n";*)
Cpdfpng.write_png {width; height; idat} o;
close_out ch;
true
| _ -> false
let write_image path_to_p2p path_to_im pdf resources name image =
let main () =
begin match Pdfimage.get_image_24bpp pdf resources image with
| Pdfimage.JPEG (stream, _) -> write_stream (name ^ ".jpg") stream
| Pdfimage.JPEG2000 (stream, _) -> write_stream (name ^ ".jpx") stream
| Pdfimage.JBIG2 (stream, _) -> write_stream (name ^ ".jbig2") stream
| Pdfimage.Raw (w, h, Pdfimage.BPP24, stream) ->
let pnm = name ^ ".pnm" in
let png = name ^ ".png" in
let fh = open_out_bin pnm in
pnm_to_channel_24 fh w h stream;
close_out fh;
begin match path_to_p2p with
| "" ->
begin match path_to_im with
"" -> Pdfe.log "Neither pnm2png nor imagemagick found. Specify with -p2p or -im\n"
| _ ->
begin match
Sys.command (Filename.quote_command path_to_im [pnm; png])
with
0 -> Sys.remove pnm
| _ ->
Pdfe.log "Call to imagemagick failed: did you specify -p2p or -im correctly?\n";
Sys.remove pnm
end
end
match Pdfimage.get_image_24bpp pdf resources image with
| Pdfimage.JPEG (stream, _) -> write_stream (name ^ ".jpg") stream
| Pdfimage.JPEG2000 (stream, _) -> write_stream (name ^ ".jpx") stream
| Pdfimage.JBIG2 (stream, _) -> write_stream (name ^ ".jbig2") stream
| Pdfimage.Raw (w, h, Pdfimage.BPP24, stream) ->
let pnm = name ^ ".pnm" in
let png = name ^ ".png" in
let fh = open_out_bin pnm in
pnm_to_channel_24 fh w h stream;
close_out fh;
begin match path_to_p2p with
| "" ->
begin match path_to_im with
"" -> Pdfe.log "Neither pnm2png nor imagemagick found. Specify with -p2p or -im\n"
| _ ->
begin match
Sys.command (Filename.quote_command path_to_p2p ~stdout:png ["-gamma"; "0.45"; "-quiet"; pnm])
Sys.command (Filename.quote_command path_to_im [pnm; png])
with
| 0 -> Sys.remove pnm
0 -> Sys.remove pnm
| _ ->
Pdfe.log "Call to pnmtopng failed: did you specify -p2p correctly?\n";
Sys.remove pnm
Pdfe.log "Call to imagemagick failed: did you specify -p2p or -im correctly?\n";
Sys.remove pnm
end
end
| _ ->
Pdfe.log (Printf.sprintf "Unsupported image type when extracting image %s " name)
end
in
match write_image_png pdf resources name image with
| true -> ()
| exception x -> Pdfe.log (Printf.sprintf "Failed to write PNG directly (%s)\n" (Printexc.to_string x)); main ()
| _ -> main ()
| _ ->
begin match
Sys.command (Filename.quote_command path_to_p2p ~stdout:png ["-gamma"; "0.45"; "-quiet"; pnm])
with
| 0 -> Sys.remove pnm
| _ ->
Pdfe.log "Call to pnmtopng failed: did you specify -p2p correctly?\n";
Sys.remove pnm
end
end
| _ ->
Pdfe.log (Printf.sprintf "Unsupported image type when extracting image %s " name)
let written = ref []