PDF4QT/Pdf4QtLib/sources/pdfredact.cpp

181 lines
6.7 KiB
C++

// Copyright (C) 2020-2021 Jakub Melka
//
// This file is part of PDF4QT.
//
// PDF4QT is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// with the written consent of the copyright owner, any later version.
//
// PDF4QT is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with PDF4QT. If not, see <https://www.gnu.org/licenses/>.
#include "pdfredact.h"
#include "pdfpainter.h"
#include "pdfdocumentbuilder.h"
#include "pdfoptimizer.h"
namespace pdf
{
PDFRedact::PDFRedact(const PDFDocument* document,
const PDFFontCache* fontCache,
const PDFCMS* cms,
const PDFOptionalContentActivity* optionalContentActivity,
const PDFMeshQualitySettings* meshQualitySettings,
QColor redactFillColor) :
m_document(document),
m_fontCache(fontCache),
m_cms(cms),
m_optionalContentActivity(optionalContentActivity),
m_meshQualitySettings(meshQualitySettings),
m_redactFillColor(redactFillColor)
{
}
PDFDocument PDFRedact::perform(Options options)
{
PDFDocumentBuilder builder;
builder.createDocument();
PDFRenderer renderer(m_document,
m_fontCache,
m_cms,
m_optionalContentActivity,
PDFRenderer::None,
*m_meshQualitySettings);
std::map<PDFObjectReference, PDFObjectReference> mapOldPageRefToNewPageRef;
for (size_t i = 0; i < m_document->getCatalog()->getPageCount(); ++i)
{
const PDFPage* page = m_document->getCatalog()->getPage(i);
PDFPrecompiledPage compiledPage;
renderer.compile(&compiledPage, i);
PDFObjectReference newPageReference = builder.appendPage(page->getMediaBox());
mapOldPageRefToNewPageRef[page->getPageReference()] = newPageReference;
if (!page->getCropBox().isEmpty())
{
builder.setPageCropBox(newPageReference, page->getCropBox());
}
if (!page->getBleedBox().isEmpty())
{
builder.setPageBleedBox(newPageReference, page->getBleedBox());
}
if (!page->getTrimBox().isEmpty())
{
builder.setPageTrimBox(newPageReference, page->getTrimBox());
}
if (!page->getArtBox().isEmpty())
{
builder.setPageArtBox(newPageReference, page->getArtBox());
}
builder.setPageRotation(newPageReference, page->getPageRotation());
PDFPageContentStreamBuilder contentStreamBuilder(&builder);
QPainterPath redactPath;
for (const PDFObjectReference& annotationReference : page->getAnnotations())
{
PDFAnnotationPtr annotation = PDFAnnotation::parse(&m_document->getStorage(), annotationReference);
if (!annotation || annotation->getType() != AnnotationType::Redact)
{
continue;
}
// We have redact annotation here
const PDFRedactAnnotation* redactAnnotation = dynamic_cast<const PDFRedactAnnotation*>(annotation.get());
Q_ASSERT(redactAnnotation);
redactPath.addPath(redactAnnotation->getRedactionRegion().getPath());
}
QMatrix matrix;
matrix.translate(0, page->getMediaBox().height());
matrix.scale(1.0, -1.0);
QPainter* painter = contentStreamBuilder.begin(newPageReference);
compiledPage.redact(redactPath, matrix, m_redactFillColor);
compiledPage.draw(painter, QRectF(), matrix, PDFRenderer::None, 1.0);
contentStreamBuilder.end(painter);
}
if (options.testFlag(CopyTitle))
{
builder.setDocumentTitle(m_document->getInfo()->title);
}
if (options.testFlag(CopyMetadata))
{
PDFObject info = m_document->getTrailerDictionary()->get("Info");
if (!info.isNull())
{
std::vector<PDFObject> copiedObjects = builder.copyFrom({ info }, m_document->getStorage(), true);
if (copiedObjects.size() == 1 && copiedObjects.front().isReference())
{
builder.setDocumentInfo(copiedObjects.front().getReference());
}
}
}
if (options.testFlag(CopyOutline))
{
PDFObject catalog = m_document->getObject(m_document->getTrailerDictionary()->get("Root"));
if (const PDFDictionary* catalogDictionary = m_document->getDictionaryFromObject(catalog))
{
if (catalogDictionary->hasKey("Outlines"))
{
QSharedPointer<PDFOutlineItem> outlineRoot = PDFOutlineItem::parse(&m_document->getStorage(), catalogDictionary->get("Outlines"));
if (outlineRoot)
{
auto resolveNamedDestination = [this, &mapOldPageRefToNewPageRef](PDFOutlineItem* item)
{
PDFActionGoTo* action = dynamic_cast<PDFActionGoTo*>(item->getAction());
if (action)
{
if (action->getDestination().isNamedDestination())
{
const PDFDestination* destination = m_document->getCatalog()->getNamedDestination(action->getDestination().getName());
if (destination)
{
action->setDestination(*destination);
}
}
PDFDestination destination = action->getDestination();
auto it = mapOldPageRefToNewPageRef.find(destination.getPageReference());
if (it != mapOldPageRefToNewPageRef.cend())
{
destination.setPageReference(it->second);
action->setDestination(destination);
}
}
};
outlineRoot->apply(resolveNamedDestination);
builder.setOutline(outlineRoot.data());
}
}
}
}
PDFDocument redactedDocument = builder.build();
PDFOptimizer optimizer(PDFOptimizer::All, nullptr);
optimizer.setDocument(&redactedDocument);
optimizer.optimize();
return optimizer.takeOptimizedDocument();
}
} // namespace pdf