chiliad.parser.pdf.extractor.vectorgraphics.operator.Invoke.java Source code

Java tutorial

Introduction

Here is the source code for chiliad.parser.pdf.extractor.vectorgraphics.operator.Invoke.java

Source

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *
 * Above you can read the original licence.
 * The original class from pdfbox project was repackage and modified.
 *
 * Copyright 2015 Kovacs Peter Tibor
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package chiliad.parser.pdf.extractor.vectorgraphics.operator;

import chiliad.parser.pdf.extractor.vectorgraphics.VectorGraphicsExtractor;
import java.awt.geom.AffineTransform;
import java.awt.geom.Area;
import java.awt.geom.GeneralPath;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.graphics.PDGraphicsState;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObject;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObjectForm;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObjectImage;
import org.apache.pdfbox.util.Matrix;
import org.apache.pdfbox.util.PDFOperator;
import org.apache.pdfbox.util.operator.OperatorProcessor;

/**
 * Implementation of content stream operator for page extractor.
 */
public class Invoke extends OperatorProcessor {

    /**
     * Log instance.
     */
    private static final Log LOG = LogFactory.getLog(Invoke.class);

    /**
     * process : Do : Paint the specified XObject (section 4.7).
     *
     * @param operator The operator that is being executed.
     * @param arguments List
     * @throws IOException If there is an error invoking the sub object.
     */
    @Override
    public void process(PDFOperator operator, List<COSBase> arguments) throws IOException {
        VectorGraphicsExtractor extractor = (VectorGraphicsExtractor) context;

        PDPage page = extractor.getPage();
        COSName objectName = (COSName) arguments.get(0);
        Map<String, PDXObject> xobjects = extractor.getResources().getXObjects();
        PDXObject xobject = (PDXObject) xobjects.get(objectName.getName());
        if (xobject == null) {
            LOG.warn("Can't find the XObject for '" + objectName.getName() + "'");
        } else if (xobject instanceof PDXObjectImage) {
            PDXObjectImage image = (PDXObjectImage) xobject;
            try {
                if (image.getImageMask()) {
                    // set the current non stroking colorstate, so that it can
                    // be used to create a stencil masked image
                    image.setStencilColor(extractor.getGraphicsState().getNonStrokingColor());
                }
                BufferedImage awtImage = image.getRGBImage();
                if (awtImage == null) {
                    LOG.warn("getRGBImage returned NULL");
                    return;//TODO PKOCH
                }
                int imageWidth = awtImage.getWidth();
                int imageHeight = awtImage.getHeight();
                double pageHeight = extractor.getPageSize().getHeight();

                LOG.debug("imageWidth: " + imageWidth + "\t\timageHeight: " + imageHeight);

                Matrix ctm = extractor.getGraphicsState().getCurrentTransformationMatrix();
                float yScaling = ctm.getYScale();
                float angle = (float) Math.acos(ctm.getValue(0, 0) / ctm.getXScale());
                if (ctm.getValue(0, 1) < 0 && ctm.getValue(1, 0) > 0) {
                    angle = (-1) * angle;
                }
                ctm.setValue(2, 1, (float) (pageHeight - ctm.getYPosition() - Math.cos(angle) * yScaling));
                ctm.setValue(2, 0, (float) (ctm.getXPosition() - Math.sin(angle) * yScaling));
                // because of the moved 0,0-reference, we have to shear in the opposite direction
                ctm.setValue(0, 1, (-1) * ctm.getValue(0, 1));
                ctm.setValue(1, 0, (-1) * ctm.getValue(1, 0));
                AffineTransform ctmAT = ctm.createAffineTransform();
                ctmAT.scale(1f / imageWidth, 1f / imageHeight);
                extractor.drawImage(awtImage, ctmAT);
            } catch (Exception e) {
                LOG.error(e, e);
            }
        } else if (xobject instanceof PDXObjectForm) {
            // save the graphics state
            context.getGraphicsStack().push((PDGraphicsState) context.getGraphicsState().clone());

            PDXObjectForm form = (PDXObjectForm) xobject;
            COSStream formContentstream = form.getCOSStream();
            // find some optional resources, instead of using the current resources
            PDResources pdResources = form.getResources();
            // if there is an optional form matrix, we have to map the form space to the user space
            Matrix matrix = form.getMatrix();
            if (matrix != null) {
                Matrix xobjectCTM = matrix.multiply(context.getGraphicsState().getCurrentTransformationMatrix());
                context.getGraphicsState().setCurrentTransformationMatrix(xobjectCTM);
            }
            if (form.getBBox() != null) {
                PDGraphicsState graphicsState = context.getGraphicsState();
                PDRectangle bBox = form.getBBox();

                float x1 = bBox.getLowerLeftX();
                float y1 = bBox.getLowerLeftY();
                float x2 = bBox.getUpperRightX();
                float y2 = bBox.getUpperRightY();

                Point2D p0 = extractor.transformedPoint(x1, y1);
                Point2D p1 = extractor.transformedPoint(x2, y1);
                Point2D p2 = extractor.transformedPoint(x2, y2);
                Point2D p3 = extractor.transformedPoint(x1, y2);

                GeneralPath bboxPath = new GeneralPath();
                bboxPath.moveTo((float) p0.getX(), (float) p0.getY());
                bboxPath.lineTo((float) p1.getX(), (float) p1.getY());
                bboxPath.lineTo((float) p2.getX(), (float) p2.getY());
                bboxPath.lineTo((float) p3.getX(), (float) p3.getY());
                bboxPath.closePath();

                Area resultClippingArea = new Area(graphicsState.getCurrentClippingPath());
                Area newArea = new Area(bboxPath);
                resultClippingArea.intersect(newArea);

                graphicsState.setCurrentClippingPath(resultClippingArea);
            }
            getContext().processSubStream(page, pdResources, formContentstream);

            // restore the graphics state
            context.setGraphicsState((PDGraphicsState) context.getGraphicsStack().pop());
        }
    }
}