Creating a TIF file with a resolution of X ppi from a PDFBox PDPage

...
PDDocument document = null;
 
try {
	// Set main options
	int imageType = BufferedImage.TYPE_BYTE_BINARY;
	int resolution = X;
	int maxPage = Integer.MAX_VALUE;
 
	// Create TIFF writer
	ImageWriter writer = null;
	ImageWriteParam writerParams = null;
	try {
		TIFFImageWriterSpi tiffspi = new TIFFImageWriterSpi();
		writer = tiffspi.createWriterInstance();
		writerParams = writer.getDefaultWriteParam();
		writerParams.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
		writerParams.setCompressionType("CCITT T.6");
		writerParams.setCompressionQuality(1.0f);
	} catch (Exception ex) {
		throw new BusinessException("Could not load the TIFF writer", ex);
	}
 
	// Create metadata for Java IO ImageWriter
	IIOMetadata metadata = createMetadata(writer, writerParams, resolution);
 
	// Load the pdf file
	document = PDDocument.load(file.getFile());
	List<PDPage> pages = (List<PDPage>) document.getDocumentCatalog().getAllPages();
 
	// Loop over the pages
	for (int i = 0; i < pages.size() && i <= maxPage; i++) {
		// Write page to image file
		File outputFile = null;
		ImageOutputStream ios = null;
		try {
			outputFile = new File(file.getFile().getCanonicalPath() + "." + i);
			ios = ImageIO.createImageOutputStream(outputFile);
			writer.setOutput(ios);
			writer.write(null, new IIOImage(pages.get(i).convertToImage(imageType, resolution), null, metadata), writerParams);
		} catch (Exception ex) {
			throw new BusinessException("Could not write the TIFF file", ex);
		} finally {
			ios.close();
		}
 
		// do something with TIF file
	}
} catch (Exception ex) {
	throw new BusinessException("Error while converting PDF to TIFF", ex);
} finally {
	try {
		if (document != null) {
			document.close();
		}
	} catch (Exception ex) {
		log.error("Error while closing PDF document", ex);
	}
}
...
 
// Internal methods
 
private IIOMetadata createMetadata(ImageWriter writer, ImageWriteParam writerParams, int resolution) throws IIOInvalidTreeException {
	// Get default metadata from writer
	ImageTypeSpecifier type = writerParams.getDestinationType();
	IIOMetadata meta = writer.getDefaultImageMetadata(type, writerParams);
 
	// Convert default metadata to TIFF metadata
	TIFFDirectory dir = TIFFDirectory.createFromMetadata(meta);
 
	// Get {X,Y} resolution tags
	BaselineTIFFTagSet base = BaselineTIFFTagSet.getInstance();
	TIFFTag tagXRes = base.getTag(BaselineTIFFTagSet.TAG_X_RESOLUTION);
	TIFFTag tagYRes = base.getTag(BaselineTIFFTagSet.TAG_Y_RESOLUTION);
 
	// Create {X,Y} resolution fields
	TIFFField fieldXRes = new TIFFField(tagXRes, TIFFTag.TIFF_RATIONAL, 1, new long[][] { { resolution, 1 } });
	TIFFField fieldYRes = new TIFFField(tagYRes, TIFFTag.TIFF_RATIONAL, 1, new long[][] { { resolution, 1 } });
 
	// Add {X,Y} resolution fields to TIFFDirectory
	dir.addTIFFField(fieldXRes);
	dir.addTIFFField(fieldYRes);
 
	// Return TIFF metadata so it can be picked up by the IIOImage
	return dir.getAsMetadata();
}