edu.umass.cs.iesl.pdf2meta.cli.extract.pdfbox.pagedrawer.BeginInlineImage.java Source code

Introduction

Here is the source code for edu.umass.cs.iesl.pdf2meta.cli.extract.pdfbox.pagedrawer.BeginInlineImage.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.
 */
package edu.umass.cs.iesl.pdf2meta.cli.extract.pdfbox.pagedrawer;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.pdfviewer.PageDrawer;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDInlinedImage;
import org.apache.pdfbox.util.ImageParameters;
import org.apache.pdfbox.util.Matrix;
import org.apache.pdfbox.util.PDFOperator;
import org.apache.pdfbox.util.operator.OperatorProcessor;

import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.List;

/**
 * Implementation of content stream operator for page drawer.
 *
 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
 * @version $Revision: 1.2 $
 */
public class BeginInlineImage extends OperatorProcessor {

    /**
     * Log instance.
     */
    private static final Log log = LogFactory.getLog(BeginInlineImage.class);

    /**
     * process : BI : begin inline image.
     * @param operator The operator that is being executed.
     * @param arguments List
     * @throws java.io.IOException If there is an error displaying the inline image.
     */
    public void process(PDFOperator operator, List<COSBase> arguments) throws IOException {
        GraphicsAwarePDFStreamEngine drawer = (GraphicsAwarePDFStreamEngine) context;

        PDPage page = drawer.getPage();
        //begin inline image object
        ImageParameters params = operator.getImageParameters();
        PDInlinedImage image = new PDInlinedImage();
        image.setImageParameters(params);
        image.setImageData(operator.getImageData());
        BufferedImage awtImage = image.createImage(context.getColorSpaces());

        if (awtImage == null) {
            log.warn("BeginInlineImage.process(): createImage returned NULL");
            return;
        }
        int imageWidth = awtImage.getWidth();
        int imageHeight = awtImage.getHeight();
        double pageHeight = drawer.getPageSize().getHeight();

        Matrix ctm = drawer.getGraphicsState().getCurrentTransformationMatrix();
        int pageRotation = page.findRotation();

        AffineTransform ctmAT = ctm.createAffineTransform();
        ctmAT.scale(1f / imageWidth, 1f / imageHeight);
        Matrix rotationMatrix = new Matrix();
        rotationMatrix.setFromAffineTransform(ctmAT);
        // calculate the inverse rotation angle
        // scaleX = m00 = cos
        // shearX = m01 = -sin
        // tan = sin/cos
        double angle = Math.atan(ctmAT.getShearX() / ctmAT.getScaleX());
        Matrix translationMatrix = null;
        if (pageRotation == 0 || pageRotation == 180) {
            translationMatrix = Matrix.getTranslatingInstance((float) (Math.sin(angle) * ctm.getXScale()),
                    (float) (pageHeight - 2 * ctm.getYPosition() - Math.cos(angle) * ctm.getYScale()));
        } else if (pageRotation == 90 || pageRotation == 270) {
            translationMatrix = Matrix.getTranslatingInstance((float) (Math.sin(angle) * ctm.getYScale()),
                    (float) (pageHeight - 2 * ctm.getYPosition()));
        }
        rotationMatrix = rotationMatrix.multiply(translationMatrix);
        rotationMatrix.setValue(0, 1, (-1) * rotationMatrix.getValue(0, 1));
        rotationMatrix.setValue(1, 0, (-1) * rotationMatrix.getValue(1, 0));
        AffineTransform at = new AffineTransform(rotationMatrix.getValue(0, 0), rotationMatrix.getValue(0, 1),
                rotationMatrix.getValue(1, 0), rotationMatrix.getValue(1, 1), rotationMatrix.getValue(2, 0),
                rotationMatrix.getValue(2, 1));
        drawer.drawImage(awtImage, at);
    }
}