I am reading in a PDF and outputting a PDF with multiple copies of the original PDF in it. I test by doing the same thing for both PDFBox and iText. iText creates a much smaller output if I duplicate each page individually.
The question: Is there another way to do this in PDFBox that results in smaller output PDFs.
For one example input file, generating two copies to the output with both tools:
- Original PDF size: 30K
- PDFBox (v 1.7.1) generated PDF: 84K
- iText (v 5.3.4) generated PDF: 35K
Java code for PDFBox (sorry to inflict error handling on you). Notice how it reads the input over and over and duplicates it as a whole:
PDFMergerUtility merger = new PDFMergerUtility();
PDDocument workplace = null;
try {
for (int cnt = 0; cnt < COPIES; ++cnt) {
PDDocument document = null;
InputStream stream = null;
try {
stream = new FileInputStream(new File(sourceFileName));
document = PDDocument.load(stream);
if (workplace == null) {
workplace = document;
} else {
merger.appendDocument(workplace, document);
}
} finally {
if (document != null && document != workplace) {
document.close();
}
if (stream != null) {
stream.close();
}
}
}
OutputStream out = null;
try {
out = new FileOutputStream(new File(destinationFileName));
workplace.save(out);
} finally {
if (out != null) {
out.close();
}
}
} catch (COSVisitorException e1) {
e1.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (workplace != null) {
try {
workplace.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
Code to do it with iText. Notice how it loads the input file page by page and transfers each page to the output:
Document document = null;
PdfReader reader = null;
InputStream inputStream = null;
FileOutputStream outputStream = null;
try {
inputStream = new FileInputStream(new File(sourceFileName));
outputStream = new FileOutputStream(new File(destinationFileName));
document = new Document();
PdfCopy copy = new PdfSmartCopy(document, outputStream);
document.open();
reader = new PdfReader(inputStream);
// loop over the pages in that document
int pdfPageNo = reader.getNumberOfPages();
for (int page = 0; page < pdfPageNo;) {
PdfImportedPage onePage = copy.getImportedPage(reader, ++page);
// duplicate each page N times
for (int i = 0; i < COPIES; ++i) {
copy.addPage(onePage);
}
}
copy.freeReader(reader);
} catch (DocumentException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
reader.close();
}
if (document != null) {
document.close();
}
try {
if (inputStream != null) {
inputStream.close();
}
if (outputStream != null) {
outputStream.close();
}
} catch (IOException e) {
// do nothing
}
}
Both are surrounded by this:
public class Duplicate {
/** The original PDF file */
private static final String sourceFileName = "PDF_CI_US2CA.pdf";
/** The resulting PDF file. */
private static final String destinationFileName = "itext_output.pdf";
private static final int COPIES = 2;
public static void main(String[] args) {
...
}
}
