tdf#109143 PDF export: don't reuse compressed bitmaps for cropped images

PDF wants to loose the pixels masked out by cropping, so the "reuse
original compressed image" optimization should not be used in that case.

Change-Id: Ifdf2cc4ff6bff0ed456a2159395314817c1cf417
Reviewed-on: https://gerrit.libreoffice.org/53743
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>

3 files changed, 51 insertions, 3 deletions

diff --git a/vcl/qa/cppunit/pdfexport/data/tdf109143.odt b/vcl/qa/cppunit/pdfexport/data/tdf109143.odt
new file mode 100644
index 000000000000..7d9afa3789e5
--- /dev/null
+++ b/vcl/qa/cppunit/pdfexport/data/tdf109143.odt
diff --git a/vcl/qa/cppunit/pdfexport/pdfexport.cxx b/vcl/qa/cppunit/pdfexport/pdfexport.cxx
index 1f527239dea7..62e1713a14cf 100644
--- a/vcl/qa/cppunit/pdfexport/pdfexport.cxx
+++ b/vcl/qa/cppunit/pdfexport/pdfexport.cxx
@@ -85,6 +85,7 @@ public:
     void testTdf66597_3();
 #endif
 #endif
+    void testTdf109143();
 
     CPPUNIT_TEST_SUITE(PdfExportTest);
 #if HAVE_FEATURE_PDFIUM
@@ -112,6 +113,7 @@ public:
     CPPUNIT_TEST(testTdf66597_3);
 #endif
 #endif
+    CPPUNIT_TEST(testTdf109143);
     CPPUNIT_TEST_SUITE_END();
 };
 
@@ -436,6 +438,46 @@ void PdfExportTest::testTdf106206()
     CPPUNIT_ASSERT(bool(it == pEnd));
 }
 
+void PdfExportTest::testTdf109143()
+{
+    // Import the bugdoc and export as PDF.
+    OUString aURL = m_directories.getURLFromSrc(DATA_DIRECTORY) + "tdf109143.odt";
+    mxComponent = loadFromDesktop(aURL);
+    CPPUNIT_ASSERT(mxComponent.is());
+
+    uno::Reference<frame::XStorable> xStorable(mxComponent, uno::UNO_QUERY);
+    utl::TempFile aTempFile;
+    aTempFile.EnableKillingFile();
+    utl::MediaDescriptor aMediaDescriptor;
+    aMediaDescriptor["FilterName"] <<= OUString("writer_pdf_Export");
+    xStorable->storeToURL(aTempFile.GetURL(), aMediaDescriptor.getAsConstPropertyValueList());
+
+    // Parse the export result.
+    vcl::filter::PDFDocument aDocument;
+    SvFileStream aStream(aTempFile.GetURL(), StreamMode::READ);
+    CPPUNIT_ASSERT(aDocument.Read(aStream));
+
+    // The document has one page.
+    std::vector<vcl::filter::PDFObjectElement*> aPages = aDocument.GetPages();
+    CPPUNIT_ASSERT_EQUAL(static_cast<size_t>(1), aPages.size());
+
+    // Get access to the only image on the only page.
+    vcl::filter::PDFObjectElement* pResources = aPages[0]->LookupObject("Resources");
+    CPPUNIT_ASSERT(pResources);
+    auto pXObjects = dynamic_cast<vcl::filter::PDFDictionaryElement*>(pResources->Lookup("XObject"));
+    CPPUNIT_ASSERT(pXObjects);
+    CPPUNIT_ASSERT_EQUAL(static_cast<size_t>(1), pXObjects->GetItems().size());
+    vcl::filter::PDFObjectElement* pXObject = pXObjects->LookupObject(pXObjects->GetItems().begin()->first);
+    CPPUNIT_ASSERT(pXObject);
+
+    // Make sure it's re-compressed.
+    auto pLength = dynamic_cast<vcl::filter::PDFNumberElement*>(pXObject->Lookup("Length"));
+    int nLength = pLength->GetValue();
+    // This failed: cropped TIFF-in-JPEG wasn't re-compressed, so crop was
+    // lost. Size was 59416, now is 11827.
+    CPPUNIT_ASSERT(nLength < 50000);
+}
+
 void PdfExportTest::testTdf106972()
 {
     // Import the bugdoc and export as PDF.
diff --git a/vcl/source/gdi/pdfextoutdevdata.cxx b/vcl/source/gdi/pdfextoutdevdata.cxx
index 013cca964441..2a7e7b1f0774 100644
--- a/vcl/source/gdi/pdfextoutdevdata.cxx
+++ b/vcl/source/gdi/pdfextoutdevdata.cxx
@@ -403,13 +403,13 @@ bool PageSyncData::PlaySyncPageAct( PDFWriter& rWriter, sal_uInt32& rCurGDIMtfAc
                             GfxLinkType eType = rGraphic.GetGfxLink().GetType();
                             if ( eType == GfxLinkType::NativeJpg )
                             {
-                                mbGroupIgnoreGDIMtfActions = rOutDevData.HasAdequateCompression(rGraphic);
+                                mbGroupIgnoreGDIMtfActions = rOutDevData.HasAdequateCompression(rGraphic, mParaRects[0], mParaRects[1]);
                                 if ( !mbGroupIgnoreGDIMtfActions )
                                     mCurrentGraphic = rGraphic;
                             }
                             else if ( eType == GfxLinkType::NativePng || eType == GfxLinkType::NativePdf )
                             {
-                                if ( eType == GfxLinkType::NativePdf || rOutDevData.HasAdequateCompression(rGraphic) )
+                                if ( eType == GfxLinkType::NativePdf || rOutDevData.HasAdequateCompression(rGraphic, mParaRects[0], mParaRects[1]) )
                                     mCurrentGraphic = rGraphic;
                             }
                         }
@@ -799,13 +799,19 @@ void PDFExtOutDevData::EndGroup( const Graphic&     rGraphic,
 }
 
 // Avoids expensive de-compression and re-compression of large images.
-bool PDFExtOutDevData::HasAdequateCompression( const Graphic &rGraphic ) const
+bool PDFExtOutDevData::HasAdequateCompression( const Graphic &rGraphic,
+                                               const tools::Rectangle & rOutputRect,
+                                               const tools::Rectangle & rVisibleOutputRect ) const
 {
     assert(rGraphic.IsGfxLink() &&
            (rGraphic.GetGfxLink().GetType() == GfxLinkType::NativeJpg ||
             rGraphic.GetGfxLink().GetType() == GfxLinkType::NativePng ||
             rGraphic.GetGfxLink().GetType() == GfxLinkType::NativePdf));
 
+    if (rOutputRect != rVisibleOutputRect)
+        // rOutputRect is the crop rectangle, re-compress cropped image.
+        return false;
+
     if (rGraphic.GetGfxLink().GetDataSize() == 0)
         return false;