How can I generate a thumbnail image of pages in a PDF document, using Java?
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Look at this [post](http://stackoverflow.com/questions/4929813/convert-pdf-to-thumbnail-image-in-java/4930488#4930488). – sdorra Feb 08 '11 at 10:59
4 Answers
20
I think http://pdfbox.apache.org/ will do what you're looking for since you can create an image from a page and then scale the image
From their example code -
/*
* 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 org.apache.pdfbox;
import java.awt.HeadlessException;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.util.List;
import org.apache.pdfbox.exceptions.InvalidPasswordException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.util.PDFImageWriter;
/**
* Convert a PDF document to an image.
*
* @author <a href="ben@benlitchfield.com">Ben Litchfield</a>
* @version $Revision: 1.6 $
*/
public class PDFToImage
{
private static final String PASSWORD = "-password";
private static final String START_PAGE = "-startPage";
private static final String END_PAGE = "-endPage";
private static final String IMAGE_FORMAT = "-imageType";
private static final String OUTPUT_PREFIX = "-outputPrefix";
private static final String COLOR = "-color";
private static final String RESOLUTION = "-resolution";
private static final String CROPBOX = "-cropbox";
/**
* private constructor.
*/
private PDFToImage()
{
//static class
}
/**
* Infamous main method.
*
* @param args Command line arguments, should be one and a reference to a file.
*
* @throws Exception If there is an error parsing the document.
*/
public static void main( String[] args ) throws Exception
{
String password = "";
String pdfFile = null;
String outputPrefix = null;
String imageFormat = "jpg";
int startPage = 1;
int endPage = Integer.MAX_VALUE;
String color = "rgb";
int resolution;
float cropBoxLowerLeftX = 0;
float cropBoxLowerLeftY = 0;
float cropBoxUpperRightX = 0;
float cropBoxUpperRightY = 0;
try
{
resolution = Toolkit.getDefaultToolkit().getScreenResolution();
}
catch( HeadlessException e )
{
resolution = 96;
}
for( int i = 0; i < args.length; i++ )
{
if( args[i].equals( PASSWORD ) )
{
i++;
if( i >= args.length )
{
usage();
}
password = args[i];
}
else if( args[i].equals( START_PAGE ) )
{
i++;
if( i >= args.length )
{
usage();
}
startPage = Integer.parseInt( args[i] );
}
else if( args[i].equals( END_PAGE ) )
{
i++;
if( i >= args.length )
{
usage();
}
endPage = Integer.parseInt( args[i] );
}
else if( args[i].equals( IMAGE_FORMAT ) )
{
i++;
imageFormat = args[i];
}
else if( args[i].equals( OUTPUT_PREFIX ) )
{
i++;
outputPrefix = args[i];
}
else if( args[i].equals( COLOR ) )
{
i++;
color = args[i];
}
else if( args[i].equals( RESOLUTION ) )
{
i++;
resolution = Integer.parseInt(args[i]);
}
else if( args[i].equals( CROPBOX ) )
{
i++;
cropBoxLowerLeftX = Float.valueOf(args[i]).floatValue();
i++;
cropBoxLowerLeftY = Float.valueOf(args[i]).floatValue();
i++;
cropBoxUpperRightX = Float.valueOf(args[i]).floatValue();
i++;
cropBoxUpperRightY = Float.valueOf(args[i]).floatValue();
}
else
{
if( pdfFile == null )
{
pdfFile = args[i];
}
}
}
if( pdfFile == null )
{
usage();
}
else
{
if(outputPrefix == null)
{
outputPrefix = pdfFile.substring( 0, pdfFile.lastIndexOf( '.' ));
}
PDDocument document = null;
try
{
document = PDDocument.load( pdfFile );
//document.print();
if( document.isEncrypted() )
{
try
{
document.decrypt( password );
}
catch( InvalidPasswordException e )
{
if( args.length == 4 )//they supplied the wrong password
{
System.err.println( "Error: The supplied password is incorrect." );
System.exit( 2 );
}
else
{
//they didn't supply a password and the default of "" was wrong.
System.err.println( "Error: The document is encrypted." );
usage();
}
}
}
int imageType = 24;
if ("bilevel".equalsIgnoreCase(color))
{
imageType = BufferedImage.TYPE_BYTE_BINARY;
}
else if ("indexed".equalsIgnoreCase(color))
{
imageType = BufferedImage.TYPE_BYTE_INDEXED;
}
else if ("gray".equalsIgnoreCase(color))
{
imageType = BufferedImage.TYPE_BYTE_GRAY;
}
else if ("rgb".equalsIgnoreCase(color))
{
imageType = BufferedImage.TYPE_INT_RGB;
}
else if ("rgba".equalsIgnoreCase(color))
{
imageType = BufferedImage.TYPE_INT_ARGB;
}
else
{
System.err.println( "Error: the number of bits per pixel must be 1, 8 or 24." );
System.exit( 2 );
}
//si une cropBox a ete specifier, appeler la methode de modification de cropbox
//changeCropBoxes(PDDocument document,float a, float b, float c,float d)
if ( cropBoxLowerLeftX!=0 || cropBoxLowerLeftY!=0 || cropBoxUpperRightX!=0 || cropBoxUpperRightY!=0 )
{
changeCropBoxes(document,cropBoxLowerLeftX, cropBoxLowerLeftY, cropBoxUpperRightX, cropBoxUpperRightY);
}
//Make the call
PDFImageWriter imageWriter = new PDFImageWriter();
boolean success = imageWriter.writeImage(document, imageFormat, password,
startPage, endPage, outputPrefix, imageType, resolution);
if (!success)
{
System.err.println( "Error: no writer found for image format '"
+ imageFormat + "'" );
System.exit(1);
}
}
catch (Exception e)
{
System.err.println(e);
}
finally
{
if( document != null )
{
document.close();
}
}
}
}
/**
* This will print the usage requirements and exit.
*/
private static void usage()
{
System.err.println( "Usage: java org.apache.pdfbox.PDFToImage [OPTIONS] <PDF file>\n" +
" -password <password> Password to decrypt document\n" +
" -imageType <image type> (" + getImageFormats() + ")\n" +
" -outputPrefix <output prefix> Filename prefix for image files\n" +
" -startPage <number> The first page to start extraction(1 based)\n" +
" -endPage <number> The last page to extract(inclusive)\n" +
" -color <string> The color depth (valid: bilevel, indexed, gray, rgb, rgba)\n" +
" -resolution <number> The bitmap resolution in dpi\n" +
" -cropbox <number> <number> <number> <number> The page area to export\n" +
" <PDF file> The PDF document to use\n"
);
System.exit( 1 );
}
private static String getImageFormats()
{
StringBuffer retval = new StringBuffer();
String[] formats = ImageIO.getReaderFormatNames();
for( int i = 0; i < formats.length; i++ )
{
retval.append( formats[i] );
if( i + 1 < formats.length )
{
retval.append( "," );
}
}
return retval.toString();
}
private static void changeCropBoxes(PDDocument document,float a, float b, float c,float d)
{
List pages = document.getDocumentCatalog().getAllPages();
for( int i = 0; i < pages.size(); i++ )
{
System.out.println("resizing page");
PDPage page = (PDPage)pages.get( i );
PDRectangle rectangle = new PDRectangle();
rectangle.setLowerLeftX(a);
rectangle.setLowerLeftY(b);
rectangle.setUpperRightX(c);
rectangle.setUpperRightY(d);
page.setMediaBox(rectangle);
page.setCropBox(rectangle);
}
}
}
dstarh
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does it keep arabic caracters as well , because i'm having an issue with this . http://stackoverflow.com/questions/16665300/setting-ttf-for-pdf-to-image-on-pdfbox – Genjuro May 22 '13 at 08:47
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4For generating images with 2.x version of pdfbox, see http://stackoverflow.com/a/23327024/580021 – Jollyjagga May 22 '17 at 12:47
5
You could also have a look at JPedal (details at http://www.jpedal.org/pdf_thumbnail.php)
mark stephens
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IcePdf is the best that I've seen (that's free) for reading pdfs. JPedal is awesome, but not free.
If you're going to be generating images from pdfs that the general public can send you, I assure you (from experience) that you'll get pdfs that will crash the JVM. (ie: If they're many-layered pdfs with all vector graphics). This pdf is an example that will crash many libraries (but is a perfectly valid PDF without anything funny like Javascript, etc).
We've gone down the route of trying to use a multitude of libraries and eventually resorting to delegating the work of creating a thumbnail to ImageMagick, which is a highly optimized C program for image manipulation.
Reverend Gonzo
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JPedal and Icepdf both have LGPL and commercial versions with different featuresets - in both cases the LGPL version has less features. There is PDF-Renderer as well but that does not support all PDF files. – mark stephens Dec 09 '10 at 14:02
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2It's been over 3 1/2 years but I wanted to thank you for your post. The sample PDF that you linked to causes a Java Heap space exception in IcePdf, which helps to illustrate the danger that user-submitted files can present. – PeterToTheThird Jul 19 '14 at 22:44
