Groovy script that extracts images from a pdf-file

pdfextractor.groovy

#! /usr/bin/env groovy

//@GrabConfig(systemClassLoader=true)

@Grab(group='ch.qos.logback', module='logback-classic', version='1.1.2')
@Grab(group='org.apache.pdfbox', module='pdfbox', version='2.0.0-RC3')

import org.apache.pdfbox.pdfwriter.*
import org.apache.pdfbox.pdmodel.*
import org.apache.pdfbox.pdmodel.font.*
import org.apache.pdfbox.pdmodel.edit.*
import org.apache.pdfbox.pdmodel.graphics.*
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
//import org.apache.pdfbox.pdmodel.graphics.PDXObject
import org.apache.pdfbox.cos.*


def appName = this.getClass().getName()
def fileType = "png"

def cli = new CliBuilder(usage:"${appName} --file <file>")
cli.with {
    f(longOpt: 'file', 'database url', args: 1, required: true)
    h(longOpt: 'help', 'Print help', required: false)
}

def options = cli.parse(args)

if (!options) return
    if (options.h) cli.usage()

println "open file: '" + options.f +"'"

PDDocument doc = null
File inputFile = new File(options.f)
File outputDir = inputFile.getParentFile()
String outfilenameTemplate = stripExt(inputFile.getName()).replaceAll(" ", "_").toLowerCase() + "-img"


try
{
	doc = PDDocument.load( inputFile )
	PDPageTree pageTree = doc.getDocumentCatalog().getPages()

	String fileName = inputFile.getName().replace(".pdf", "_cover");
	int totalImages = -1;

	for ( PDPage page : pageTree.iterator() ) {

		PDResources pdResources = page.getResources();

		for ( COSName xObjCosName : pdResources.getXObjectNames() ) {

			//println xObjCosName
			PDXObject pdxObj = pdResources.getXObject(xObjCosName)
			
			if ( pdxObj instanceof PDImageXObject ) {

				PDImageXObject pdImageXObject = (PDImageXObject) pdxObj
				BufferedImage bufferedImage = pdImageXObject.getImage()

				println(bufferedImage)
				File outFile = new File( outputDir, outfilenameTemplate + totalImages + "." + fileType)
				ImageIO.write( bufferedImage, fileType, outFile );
				println( "writtten: " + outFile )

				totalImages++;
			}
		}
	}
}
finally
{
   if( doc != null )
   {
      doc.close();
   }
}


static String stripExt (String str) {

        if (str == null) return null;
        int pos = str.lastIndexOf(".");
        if (pos == -1) return str;
        return str.substring(0, pos);
}