Question

我有SVG文档，我在工作流程的最后将它们通过ghostscript转换为PDF。现在，我必须添加一个新功能。我需要用PDF内容替换SVG中的某些元素。不是只需叠加，就可以按比例旋转和缩放，下面是一个图像：

“示例”

我的问题是，有什么方法可以使用ghostscript吗？

目前，我只是将其作为SVG图像元素的光栅化图像插入，但是我需要将其作为打印矢量。

注意：我只需要从插入的PDF中获取第一页。

我知道有一个pdftk可以将一个PDF文件覆盖在另一个文件上，但是我无法缩放和旋转覆盖的PDF文档。

Answer 1

好的，所以我担心，由于Ghostscript PDF解释器为解决安全漏洞而进行了近期更改，因此该代码仅适用于9.26以下的版本。在将来的PDF中，itnerpreter将会被更改，并且会有更好的方法来实现这一目标，但是我担心这是一个长期目标。目前，要使用此代码，您需要坚持使用旧版本。

执行此操作的PostScript程序如下：

%!PS

%%
%% This code is copied from pdf_main.ps, pdfshowpage_finish
%% sadly that routine always calls showpage, and we want that
%% to be under our control, so we have to duplicate the code
%% here. Not only that but it uses GS extensions which aren't
%% available outside of startup, so some things it simply can't
%% replicate. As a result some of the error handling is less
%% good.
%%
%% I plan to extend the PDF interpreter with two new
%% routines, pdfnoshowpage_finish and then have both
%% that and pdfshowpage_finish call pdfoptionalshowpage_finish
%% which will take a boolean determining whether to actually
%% call the showpage. At that time we'll alter this code.
%%
/draw_page_content {    % <pagedict> pdfshowpage_finish -
   save /PDFSave exch store
   /PDFdictstackcount countdictstack store
   /PDFexecstackcount count 2 sub store
   (before exec) VMDEBUG

   % set up color space substitution (this must be inside the page save)
   pdfshowpage_setcspacesub

        % Display the actual page contents.
   8 dict begin
   /BXlevel 0 def
   /BMClevel 0 def
   /OFFlevels 0 dict def
   /BGDefault currentblackgeneration def
   /UCRDefault currentundercolorremoval def
        %****** DOESN'T HANDLE COLOR TRANSFER YET ******
   /TRDefault currenttransfer def
  matrix currentmatrix 
  2 dict
  dictbeginpage setmatrix
  /DefaultQstate qstate store

  count 1 sub /pdfemptycount exch store
        % If the page uses any transparency features, show it within
        % a transparency group.
  dup pageusestransparency dup /PDFusingtransparency exch def {
    % Show the page within a PDF 1.4 device filter.
    0 .pushpdf14devicefilter {
      /DefaultQstate qstate store       % device has changed -- reset DefaultQstate
      % If the page has a Group, enclose contents in transparency group.
      % (Adobe Tech Note 5407, sec 9.2)
      dup /Group knownoget {
        1 index /CropBox pget {
          /CropBox exch
        } {
          1 index get_media_box pop /MediaBox exch
        } ifelse
        oforce_elems normrect_elems fix_empty_rect_elems 4 array astore .beginformgroup 
        showpagecontents
        .endtransparencygroup
      } {
        showpagecontents
      } ifelse
    } stopped {
      % abort the transparency device 
      .abortpdf14devicefilter
      /DefaultQstate qstate store   % device has changed -- reset DefaultQstate
      stop
    } if .poppdf14devicefilter
    /DefaultQstate qstate store % device has changed -- reset DefaultQstate
  } {
    showpagecontents
  } ifelse
  .free_page_resources
  % todo: mixing drawing ops outside the device filter could cause
  % problems, for example with the pnga device.

  end           % scratch dict
  % Some PDF files don't have matching q/Q (gsave/grestore) so we need
  % to clean up any left over dicts from the dictstack

  PDFdictstackcount //false
  { countdictstack 2 index le { exit } if
    currentdict /n known not or
    end
  } loop 

  pop
  count PDFexecstackcount sub { pop } repeat
  Repaired      % pass Repaired state around the restore
  PDFSave restore
  currentglobal pdfdict gcheck .setglobal
  .setglobal
  /Repaired exch def
} def

% And now, draw the page from teh first PDF file
(d:/temp/SO/target.pdf) (r) file runpdfbegin
save
1 pdfgetpage
dup /Page exch store                                         draw_page_content
restore                                      
runpdfend

% and then the page from the secodn PDF file
(d:/temp/SO/source.pdf) (r) file runpdfbegin
save
1 pdfgetpage
dup /Page exch store                                        

% Before drawing the second page, adjust the CTM so
% that the bottom left corner of the page is co-incident
% with the bottom left of the area we want to draw the
% page in
75 575 translate

% adjust the size of the output
0.11 0.11 scale

% and rotate it
-46 rotate

draw_page_content
restore                                      
runpdfend

showpage

将其保存在文件中，将其称为test.ps，并适当调整PostScript程序中的路径。然后使用以下命令运行Ghostscript：gs -sDEVICE=pdfwrite -sOutputFile=out.pdf test.ps，您将得到一个PDF文件，类似于我想的样子。显然，您还需要更改数字以进行平移/缩放/旋转。

Answer 2

我在这里发布了一个解决方案，该解决方案支持剪切粘贴的PDF文件，以防万一将来有人需要它。我在draw_page_content中添加了其他参数来支持它。我似乎看到“ dict beginpage setmatrix”命令以某种方式覆盖了剪切路径，并且仅应在该命令之后进行设置。我不是PostScript专家，但至少此解决方案有效。再次感谢KenS的帮助。

%!PS

%%
%% This code is copied from pdf_main.ps, pdfshowpage_finish
%% sadly that routine always calls showpage, and we want that
%% to be under our control, so we have to duplicate the code
%% here. Not only that but it uses GS extensions which aren't
%% available outside of startup, so some things it simply can't
%% replicate. As a result some of the error handling is less
%% good.
%%
%% I plan to extend the PDF interpreter with two new
%% routines, pdfnoshowpage_finish and then have both
%% that and pdfshowpage_finish call pdfoptionalshowpage_finish
%% which will take a boolean determining whether to actually
%% call the showpage. At that time we'll alter this code.
%%
/draw_page_content {    % <pagedict> pdfshowpage_finish -
   /clipx exch def /clipy exch def /clip_width exch def /clip_height exch def /should_clip exch def
   save /PDFSave exch store
   /PDFdictstackcount countdictstack store
   /PDFexecstackcount count 2 sub store
   (before exec) VMDEBUG

   % set up color space substitution (this must be inside the page save)
   pdfshowpage_setcspacesub

        % Display the actual page contents.
   8 dict begin
   /BXlevel 0 def
   /BMClevel 0 def
   /OFFlevels 0 dict def
   /BGDefault currentblackgeneration def
   /UCRDefault currentundercolorremoval def
        %****** DOESN'T HANDLE COLOR TRANSFER YET ******
   /TRDefault currenttransfer def
  matrix currentmatrix 
  2 dict
  dictbeginpage setmatrix

  % set clipping here
  should_clip 0 gt
  {
    newpath clipx clipy moveto clipx clipy clip_height add lineto clipx clip_width add clipy clip_height add lineto clipx clip_width add clipy lineto closepath clip
  }
  {
  }
  ifelse

  /DefaultQstate qstate store

  count 1 sub /pdfemptycount exch store
        % If the page uses any transparency features, show it within
        % a transparency group.
  dup pageusestransparency dup /PDFusingtransparency exch def {
    % Show the page within a PDF 1.4 device filter.
    0 .pushpdf14devicefilter {
      /DefaultQstate qstate store       % device has changed -- reset DefaultQstate
      % If the page has a Group, enclose contents in transparency group.
      % (Adobe Tech Note 5407, sec 9.2)
      dup /Group knownoget {
        1 index /CropBox pget {
          /CropBox exch
        } {
          1 index get_media_box pop /MediaBox exch
        } ifelse
        oforce_elems normrect_elems fix_empty_rect_elems 4 array astore .beginformgroup 
        showpagecontents
        .endtransparencygroup
      } {
        showpagecontents
      } ifelse
    } stopped {
      % abort the transparency device 
      .abortpdf14devicefilter
      /DefaultQstate qstate store   % device has changed -- reset DefaultQstate
      stop
    } if .poppdf14devicefilter
    /DefaultQstate qstate store % device has changed -- reset DefaultQstate
  } {
    showpagecontents
  } ifelse
  .free_page_resources
  % todo: mixing drawing ops outside the device filter could cause
  % problems, for example with the pnga device.

  end           % scratch dict
  % Some PDF files don't have matching q/Q (gsave/grestore) so we need
  % to clean up any left over dicts from the dictstack

  PDFdictstackcount //false
  { countdictstack 2 index le { exit } if
    currentdict /n known not or
    end
  } loop 

  pop
  count PDFexecstackcount sub { pop } repeat
  Repaired      % pass Repaired state around the restore
  PDFSave restore
  currentglobal pdfdict gcheck .setglobal
  .setglobal
  /Repaired exch def
} bind def

% And now, draw the page from teh first PDF file
(/opt/files/main.pdf) (r) file runpdfbegin
save
1 pdfgetpage
dup /Page exch store 0 1125 1125 0 0 draw_page_content
restore                                      
runpdfend

gsave

% and then the page from the next PDF file
(/opt/files/placement1.pdf) (r) file runpdfbegin
save
1 pdfgetpage
dup /Page exch store                                        

% Before drawing the second page, adjust the CTM so
% that the bottom left corner of the page is co-incident
% with the bottom left of the area we want to draw the
% page in
120 120 translate

% and rotate it
25 rotate

% adjust the size of the output
0.7 0.7 scale

%let's skew file
[1 0 1.3 1 0 0] concat

% draw file and clip it
1 100 100 0 0 draw_page_content

restore                                      
runpdfend
grestore

showpage

有没有一种方法可以将一个旋转的PDF文档覆盖在另一个文档上？

2 个答案: