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#include "qpdf_xobject.h"
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//#include <qpdf/Types.h>
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#include <qpdf/QPDF.hh>
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#include <qpdf/Pl_Discard.hh>
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#include <qpdf/Pl_Count.hh>
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#include <qpdf/Pl_Concatenate.hh>
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#include "qpdf_tools.h"
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#include "qpdf_pdftopdf.h"
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// TODO: need to remove Struct Parent stuff (or fix)
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// NOTE: use /TrimBox to position content inside Nup cell, /BleedBox to clip against
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class CombineFromContents_Provider : public QPDFObjectHandle::StreamDataProvider {
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CombineFromContents_Provider(const std::vector<QPDFObjectHandle> &contents);
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void provideStreamData(int objid, int generation, Pipeline* pipeline);
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std::vector<QPDFObjectHandle> contents;
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CombineFromContents_Provider::CombineFromContents_Provider(const std::vector<QPDFObjectHandle> &contents)
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void CombineFromContents_Provider::provideStreamData(int objid, int generation, Pipeline* pipeline)
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Pl_Concatenate concat("concat", pipeline);
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const int clen=contents.size();
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for (int iA=0;iA<clen;iA++) {
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contents[iA].pipeStreamData(&concat, true, false, false);
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concat.manualFinish();
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To convert a page to an XObject there are several keys to consider:
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/Type /Page -> /Type /XObject (/Type optional for XObject)
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-> [/FormType 1] (optional)
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/Parent ? ? R -> remove
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/Resources dict -> copy
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/MediaBox rect [/CropBox /BleedBox /TrimBox /ArtBox]
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-> /BBox (use TrimBox [+ Bleed consideration?], with fallback to /MediaBox)
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note that /BBox is in *Form Space*, see /Matrix!
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[/BoxColorInfo dict] (used for guidelines that may be shown by viewer)
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[/Contents asfd] -> concatenate into stream data of the XObject (page is a dict, XObject a stream)
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[/Rotate 90] ... must be handled (either use CTM where XObject is /used/ -- or set /Matrix)
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[/UserUnit] (PDF 1.6) -> to /Matrix ? -- it MUST be handled.
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[/Thumb stream] -> remove, not needed any more / would have to be regenerated (combined)
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[/B] article beads -- ignore for now
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[/Dur] -> remove (transition duration)
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[/Trans] -> remove (transitions)
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[/AA] -> remove (additional-actions)
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[/Metadata] what shall we do?? (kill: we can't combine XML)
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[/PieceInfo] -> remove, we can't combine private app data (?)
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[/LastModified date] (opt except /PieceInfo) -> see there
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[/PZ] -> remove, can't combine/keep (preferred zoom level)
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[/SeparationInfo] -> remove, no way to keep this (needed for separation)
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[/ID] related to web capture -- ignore/kill?
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[/StructParents] (opt except pdf contains "structural content items")
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-> copy (is this correct?)
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[/Annots] annotations -- ignore for now
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[/Tabs] tab order for annotations (/R row, /C column, /S structure order) -- see /Annots
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[/TemplateInstantiated] (reqd, if page was created from named page obj, 1.5) -- ? just ignore?
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[/PresSteps] -> remove (sub-page navigation for presentations) [no subpage navigation for printing / nup]
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[/VP] viewport rects -- ignore/drop or recalculate into new page
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QPDFObjectHandle makeXObject(QPDF *pdf,QPDFObjectHandle page)
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page.assertPageObject();
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QPDFObjectHandle ret=QPDFObjectHandle::newStream(pdf);
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QPDFObjectHandle dict=ret.getDict();
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dict.replaceKey("/Type",QPDFObjectHandle::newName("/XObject")); // optional
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dict.replaceKey("/Subtype",QPDFObjectHandle::newName("/Form")); // required
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// dict.replaceKey("/FormType",QPDFObjectHandle::newInteger(1)); // optional
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QPDFObjectHandle box=getTrimBox(page); // already in "form space"
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dict.replaceKey("/BBox",box); // reqd
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// [/Matrix .] ... default is [1 0 0 1 0 0]; we incorporate /UserUnit and /Rotate here
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if (page.hasKey("/UserUnit")) {
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mtx.scale(page.getKey("/UserUnit").getNumericValue());
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// transform, so that bbox is [0 0 w h] (in outer space, but after UserUnit)
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Rotation rot=getRotate(page);
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// calculate rotation effect on [0 0 w h]
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PageRect bbox=getBoxAsRect(box),tmp;
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tmp.rotate_move(rot,bbox.width,bbox.height);
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// tmp.rotate_move moves the bbox; we must achieve this move with the matrix.
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mtx.translate(tmp.left,tmp.bottom); // 1. move origin to end up at left,bottom after rotation
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mtx.rotate(rot); // 2. rotate coordinates according to /Rotate
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mtx.translate(-bbox.left,-bbox.bottom); // 3. move origin from 0,0 to "form space"
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dict.replaceKey("/Matrix",mtx.get());
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dict.replaceKey("/Resources",page.getKey("/Resources"));
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if (page.hasKey("/Group")) {
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dict.replaceKey("/Group",page.getKey("/Group")); // (transparency); opt, copy if there
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// ?? /StructParents ... can basically copy from page, but would need fixup in Structure Tree
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// FIXME: remove (globally) Tagged spec (/MarkInfo), and Structure Tree
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// Note: [/Name] (reqd. only in 1.0 -- but there we even can't use our normal img/patter procedures)
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// QPDFObjectHandle filter=QPDFObjectHandle::newArray();
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// QPDFObjectHandle decode_parms=QPDFObjectHandle::newArray();
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// null leads to use of "default filters" from qpdf's settings
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QPDFObjectHandle filter=QPDFObjectHandle::newNull();
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QPDFObjectHandle decode_parms=QPDFObjectHandle::newNull();
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std::vector<QPDFObjectHandle> contents=page.getPageContents(); // (will assertPageObject)
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auto ph=PointerHolder<QPDFObjectHandle::StreamDataProvider>(new CombineFromContents_Provider(contents));
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ret.replaceStreamData(ph,filter,decode_parms);
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we will have to fix up the structure tree (e.g. /K in element), when copying /StructParents;
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(there is /Pg, which has to point to the containing page, /Stm when it's not part of the page's content stream
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i.e. when it is in our XObject!; then there is /StmOwn ...)
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when not copying, we have to remove the structure tree completely (also /MarkInfo dict)
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Still this might not be sufficient(?), as there are probably BDC and EMC operators in the stream.
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/* /XObject /Form has
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/BBox rect from crop box, or recalculate
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[/Matrix .] ... default is [1 0 0 1 0 0] --- we have to incorporate /UserUnit here?!
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[/Resources dict] from page.
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[/Group dict] used for transparency -- can copy from page
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[/Ref dict] not needed; for external reference
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[/Metadata] not, as long we can not combine.
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[/PieceInfo] can copy, but not combine
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[/LastModified date] copy if /PieceInfo there
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[/StructParent] . don't want to be one ... have to read more spec
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[/StructParents] . copy from page!
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[/OPI] no opi version. don't set
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[/OC] is this optional content? NO! not needed.
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[/Name] (only reqd. in 1.0 -- but there we even can't use our normal img/patter procedures)
added
removed
filter/pdftopdf/qpdf_xobject.cc
