Develop Reference

Why does PDFBox read the image width/height wrong? (always assumes "width" is the bigger one)

I'm using the PDFBox library (see here) to convert an image to PDF. The goal is to have a image scaled to a full A4 page in the PDF file. And it works well, except one thing:
The image height and width seem to be mixed up. The width is always assumed to be the bigger value of them both. I have 2 images: One has the dimensions (according to the Windows file details) 4032x2268 (landscape) and the other one 2268x4032 (portrait).
When i load the images in PDFBox, the width is always 4032 and the height 2268. The goal is to create a landscape PDF for one and a portrait PDF for the other one. This weird "bug" (?) causes the portrait image to convert to a landscape PDF which of course causes the image to be rotated (which is inconventient).
Here's the relevant part of my code:
public byte[] imageToPDF(MultipartFile file) throws IOException {
PDDocument pdf = new PDDocument();
PDImageXObject pdImage = PDImageXObject.createFromByteArray(pdf, file.getBytes(), file.getOriginalFilename());
// scale image to fit the full page
PDPage page;
int imageWidth;
int imageHeight;
if (pdImage.getWidth() > pdImage.getHeight()) {
// landscape pdf
float pageHeight = PDRectangle.A4.getWidth();
float pageWidth = PDRectangle.A4.getHeight();
page = new PDPage(new PDRectangle(pageWidth, pageHeight));
imageWidth = (int)pageWidth;
imageHeight = (int)(((double)imageWidth / (double)pdImage.getWidth()) * (double)pdImage.getHeight());
} else {
// portrait pdf
float pageHeight = PDRectangle.A4.getHeight();
float pageWidth = PDRectangle.A4.getWidth();
page = new PDPage(new PDRectangle(pageWidth, pageHeight));
imageHeight = (int)pageHeight;
imageWidth = (int)(((double)imageHeight / (double)pdImage.getHeight()) * (double)pdImage.getWidth());
}
...
}
pdImage.getWidth() is always greater than pdImage.getHeight(), no matter which of the two images I use. Does anyone have an idea?

How to correctly copy pages from one PDF document to another using iTextPDF 7?

The following code is a simplified version of a method that receives a destination pdf document and a source pdf document and copies the pages from the source to the destination. The page copy has to be a little smaller (95%) of the original one since the page in the destination document will receive some extra text as header and footer.
try {
for(int pageIndex = 1; pageIndex<=pdfSource.getNumberOfPages(); ++pageIndex) {
PdfPage sourcePage = pdfSource.getPage(pageIndex);
Rectangle sourceRect = sourcePage.getPageSizeWithRotation();
PdfPage page = pdfDest.addNewPage(PageSize.A4);
// Transformation matrix
PdfCanvas canvas = new PdfCanvas(page);
AffineTransform transformationMatrix = AffineTransform.getScaleInstance(
(page.getPageSize().getWidth() / sourcePage.getWidth()) * 0.95,
(page.getPageSize().getHeight() / sourcePage.getHeight()) * 0.95);
canvas.concatMatrix(transformationMatrix);
try {
PdfFormXObject pageCopy = sourcePage.copyAsFormXObject(pdfDestino);
float x = (float)(page.getPageSize().getWidth()*0.05);
float y = (float)(page.getPageSize().getHeight()*0.05);
canvas.addXObject(pageCopy, x, y);
pageCopy.flush();
} catch(Exception e) {
// bla bla bla
}
// Reset tansformations
transformationMatrix = AffineTransform.getScaleInstance(
sourceRect.getWidth() / page.getPageSize().getWidth(),
sourceRect.getHeight() / page.getPageSize().getHeight()
);
canvas.concatMatrix(transformationMatrix);
canvas.setFillColorRgb(0.0f, 0.0f, 0.65f)
.setFontAndSize(PdfFontFactory.createFont(FontConstants.COURIER), 11);
// Adding some extra text
// blah blah blah
}
} finally {
pdfSource.close();
}
As a general rule, this method will be called many times, since many documents will be appended to the destination PDF document.
All works fine, except when we have a big list of source documents. In this context, big is above 100.
So, when we have a list of, for instance, 30 source documents, all of then are correctly processed and the destination document will have the pages of all the 30 documents.
When this list is longer than 100 documents, we have a OutOfMemory exception. We think there is a memory leak here, but we can't find it.
What are we missing?

PDFBOX unable to find number of pixels which contain a particular character

I am using PDFBOX for pdf creation. In pdfbox is there any function which will give the font size in pixels? For example letters A and a, will take different spaces for printing. Where obviosely A will take more pixels than a. How can I get find number of pixels supposed to take a character or a word?

First of all the concept of pixels is a bit vague.
Generally a document is of a certain size, e.g. inches/cm etc.
The javadocs for PDFBox shows that PDFont has a few methods to determine the width of a string or character.
Take a look at for example these pages:
getStringWidth(String text)
getWidth(int code)
getWidthFromFont(int code)
These units are in 1/1000 of an Em. Also see this page.
For a full example:
float fontSize = 12;
String text = "a";
PDRectangle pageSize = PDRectangle.A4;
PDFont font = PDType1Font.HELVETICA_BOLD;
PDDocument doc = new PDDocument();
PDPage page = new PDPage(pageSize);
doc.addPage(page);
PDPageContentStream stream = new PDPageContentStream(doc,page);
stream.setFont( font, fontSize );
// charWidth is in points multiplied by 1000.
double charWidth = font.getStringWidth(text);
charWidth *= fontSize; // adjust for font-size.
stream.beginText();
stream.moveTextPositionByAmount(0,10);
float widthLeft = pageSize.getWidth();
widthLeft *= 1000.0; //due to charWidth being x1000.
while(widthLeft > charWidth){
stream.showText(text);
widthLeft -= charWidth;
}
stream.close();
// Save the results and ensure that the document is properly closed:
doc.save( "example.pdf");
doc.close();

Add page numbers to Merged PDF with different Pages sizes using IText API

I am trying to add Page numbers to merged PDF files using Itext on top right corner of the pages, but my pdf content size is different, after merging the PDF's while trying to print the page sizes i am getting approximately same sizes(height and width) on each page, but i am not able see page numbers, because of content size difference. please see below code and pdf attachements which am using for merging PDFs and adding page numbers.
public class PageNumber {
public static void main(String[] args) {
PageNumber number = new PageNumber();
try {
String DOC_ONE_PATH = "C:/Users/Admin/Downloads/codedetailsforartwork/elebill.pdf";
String DOC_TWO_PATH = "C:/Users/Admin/Downloads/codedetailsforartwork/PP-P0109916.pdf";
String DOC_THREE_PATH = "C:/Users/Admin/Downloads/codedetailsforartwork/result.pdf";
String[] files = { DOC_ONE_PATH, DOC_TWO_PATH };
Document document = new Document();
PdfCopy copy = new PdfCopy(document, new FileOutputStream(DOC_THREE_PATH));
document.open();
PdfReader reader;
int n;
for (int i = 0; i < files.length; i++) {
reader = new PdfReader(files[i]);
n = reader.getNumberOfPages();
for (int page = 0; page < n; ) {
copy.addPage(copy.getImportedPage(reader, ++page));
}
copy.freeReader(reader);
reader.close();
}
// step 5
document.close();
number.manipulatePdf(
"C:/Users/Admin/Downloads/codedetailsforartwork/result.pdf",
"C:/Users/Admin/Downloads/codedetailsforartwork/PP-P0109916_1.pdf");
} catch (IOException | DocumentException | APIException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void manipulatePdf(String src, String dest)
throws IOException, DocumentException, APIException {
PdfReader reader = new PdfReader(src);
int n = reader.getNumberOfPages();
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
PdfContentByte pagecontent;
for (int i = 0; i < n;) {
pagecontent = stamper.getOverContent(++i);
System.out.println(i);
com.itextpdf.text.Rectangle pageSize = reader.getPageSize(i);
pageSize.normalize();
float height = pageSize.getHeight();
float width = pageSize.getWidth();
System.out.println(width + " " + height);
ColumnText.showTextAligned(pagecontent, Element.ALIGN_CENTER,
new Phrase(String.format("page %d of %d", i, n)),
width - 200, height-85, 0);
}
stamper.close();
reader.close();
}
}
PDF files Zip

#Bruno's answer explains and/or references answer with explanations for all relevant facts on the issue at hand.
In a nutshell, the two issues of the OP's code are:
he uses reader.getPageSize(i); while this indeed returns the page size, PDF viewers do not display the whole page size but merely the crop box on it. Thus, the OP should use reader.getCropBox(i) instead. According to the PDF specification, "the crop box defines the region to which the contents of the page shall be clipped (cropped) when displayed or printed. ... The default value is the page’s media box."
he uses pageSize.getWidth() and pageSize.getHeight() to determine the upper right corner but should use pageSize.getRight() and pageSize.getTop() instead. The boxes defining the PDF coordinate system may not have the origin in their lower left corner.

I don't understand why you are defining the position of the page number like this:
com.itextpdf.text.Rectangle pageSize = reader.getPageSize(i);
pageSize.normalize();
float height = pageSize.getHeight();
float width = pageSize.getWidth();
where you use
x = width - 200;
y = height - 85;
How does that make sense?
If you have an A4 page in portrait with (0,0) as the coordinate of the lower-left corner, the page number will be added at position x = 395; y = 757. However, (0,0) isn't always the coordinate of the lower-left corner, so the first A4 page with the origin at another position will already put the page number at another position. If the page size is different, the page number will move to other places.
It's as if you're totally unaware of previously answered questions such as How should I interpret the coordinates of a rectangle in PDF? and Where is the Origin (x,y) of a PDF page?
I know, I know, finding these specific answers on StackOverflow is hard, but I've spent many weeks organizing the best iText questions on StackOverflow on the official web site. See for instance: How should I interpret the coordinates of a rectangle in PDF? and Where is the origin (x,y) of a PDF page?
These Q&As are even available in a free ebook! If you take a moment to educate yourself by reading the documentation, you'll find the answer to the question How to position text relative to page? that was already answered on StackOverflow in 2013: How to position text relative to page using iText?
For instance, if you want to position your page number at the bottom and in the middle, you need to define your coordinates like this:
float x = pageSize.getBottom() + 10;
float y = pageSize.getLeft() + pageSize.getWidth() / 2;
ColumnText.showTextAligned(pagecontent, Element.ALIGN_CENTER,
new Phrase(String.format("page %d of %d", i, n)), x, y, 0);
I hope this answer will inspire you to read the documentation. I've spent weeks of work on organizing that documentation and it's frustrating when I discover that people don't read it.

How to watermark PDFs using text or images?

I have a bunch of PDF documents in a folder and I want to augment them with a watermark. What are my options from a Java serverside context?
Preferably the watermark will support transparency. Both vector and raster is desirable.

Please take a look at the TransparentWatermark2 example. It adds transparent text on each odd page and a transparent image on each even page of an existing PDF document.
This is how it's done:
public void manipulatePdf(String src, String dest) throws IOException, DocumentException {
PdfReader reader = new PdfReader(src);
int n = reader.getNumberOfPages();
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
// text watermark
Font f = new Font(FontFamily.HELVETICA, 30);
Phrase p = new Phrase("My watermark (text)", f);
// image watermark
Image img = Image.getInstance(IMG);
float w = img.getScaledWidth();
float h = img.getScaledHeight();
// transparency
PdfGState gs1 = new PdfGState();
gs1.setFillOpacity(0.5f);
// properties
PdfContentByte over;
Rectangle pagesize;
float x, y;
// loop over every page
for (int i = 1; i <= n; i++) {
pagesize = reader.getPageSizeWithRotation(i);
x = (pagesize.getLeft() + pagesize.getRight()) / 2;
y = (pagesize.getTop() + pagesize.getBottom()) / 2;
over = stamper.getOverContent(i);
over.saveState();
over.setGState(gs1);
if (i % 2 == 1)
ColumnText.showTextAligned(over, Element.ALIGN_CENTER, p, x, y, 0);
else
over.addImage(img, w, 0, 0, h, x - (w / 2), y - (h / 2));
over.restoreState();
}
stamper.close();
reader.close();
}
As you can see, we create a Phrase object for the text and an Image object for the image. We also create a PdfGState object for the transparency. In our case, we go for 50% opacity (change the 0.5f into something else to experiment).
Once we have these objects, we loop over every page. We use the PdfReader object to get information about the existing document, for instance the dimensions of every page. We use the PdfStamper object when we want to stamp extra content on the existing document, for instance adding a watermark on top of each single page.
When changing the graphics state, it is always safe to perform a saveState() before you start and to restoreState() once you're finished. You code will probably also work if you don't do this, but believe me: it can save you plenty of debugging time if you adopt the discipline to do this as you can get really strange effects if the graphics state is out of balance.
We apply the transparency using the setGState() method and depending on whether the page is an odd page or an even page, we add the text (using ColumnText and an (x, y) coordinate calculated so that the text is added in the middle of each page) or the image (using the addImage() method and the appropriate parameters for the transformation matrix).
Once you've done this for every page in the document, you have to close() the stamper and the reader.
Caveat:
You'll notice that pages 3 and 4 are in landscape, yet there is a difference between those two pages that isn't visible to the naked eye. Page 3 is actually a page of which the size is defined as if it were a page in portrait, but it is rotated by 90 degrees. Page 4 is a page of which the size is defined in such a way that the width > the height.
This can have an impact on the way you add a watermark, but if you use getPageSizeWithRotation(), iText will adapt. This may not be what you want: maybe you want the watermark to be added differently.
Take a look at TransparentWatermark3:
public void manipulatePdf(String src, String dest) throws IOException, DocumentException {
PdfReader reader = new PdfReader(src);
int n = reader.getNumberOfPages();
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
stamper.setRotateContents(false);
// text watermark
Font f = new Font(FontFamily.HELVETICA, 30);
Phrase p = new Phrase("My watermark (text)", f);
// image watermark
Image img = Image.getInstance(IMG);
float w = img.getScaledWidth();
float h = img.getScaledHeight();
// transparency
PdfGState gs1 = new PdfGState();
gs1.setFillOpacity(0.5f);
// properties
PdfContentByte over;
Rectangle pagesize;
float x, y;
// loop over every page
for (int i = 1; i <= n; i++) {
pagesize = reader.getPageSize(i);
x = (pagesize.getLeft() + pagesize.getRight()) / 2;
y = (pagesize.getTop() + pagesize.getBottom()) / 2;
over = stamper.getOverContent(i);
over.saveState();
over.setGState(gs1);
if (i % 2 == 1)
ColumnText.showTextAligned(over, Element.ALIGN_CENTER, p, x, y, 0);
else
over.addImage(img, w, 0, 0, h, x - (w / 2), y - (h / 2));
over.restoreState();
}
stamper.close();
reader.close();
}
In this case, we don't use getPageSizeWithRotation() but simply getPageSize(). We also tell the stamper not to compensate for the existing page rotation: stamper.setRotateContents(false);
Take a look at the difference in the resulting PDFs:
In the first screen shot (showing page 3 and 4 of the resulting PDF of TransparentWatermark2), the page to the left is actually a page in portrait rotated by 90 degrees. iText however, treats it as if it were a page in landscape just like the page to the right.
In the second screen shot (showing page 3 and 4 of the resulting PDF of TransparentWatermark3), the page to the left is a page in portrait rotated by 90 degrees and we add the watermark as if the page is in portrait. As a result, the watermark is also rotated by 90 degrees. This doesn't happen with the page to the right, because that page has a rotation of 0 degrees.
This is a subtle difference, but I thought you'd want to know.
If you want to read this answer in French, please read Comment créer un filigrane transparent en PDF?

Best option is iText. Check a watermark demo here
Important part of the code (where the watermar is inserted) is this:
public class Watermark extends PdfPageEventHelper {
#Override
public void onEndPage(PdfWriter writer, Document document) {
// insert here your watermark
}
Read carefully the example.
onEndPage() method will be something like (in my logo-watermarks I use com.itextpdf.text.Image;):
Image image = Image.getInstance(this.getClass().getResource("/path/to/image.png"));
// set transparency
image.setTransparency(transparency);
// set position
image.setAbsolutePosition(absoluteX, absoluteY);
// put into document
document.add(image);