I need to simultaneously stamp both a string (details of the user) and an image containing an actual signature in a pdfDocument. The string and image are successfully stamped on the document, however, the image of the actual signature is being stretched to fit the rectangle of the whole signature. how do i fix this and manipulate the size and position of the image?
I used both Layer2Text and Image function in one stamper declaration. Can anyone help me?
Thanks in advance
Instead of merely setting the Layer2Text and Image and letting iTextSharp arrange everything, you can create the signature appearance all by yourself on the PdfTemplate returned by GetLayer(2).
If you need some inspiration on how to fill that layer, you can look at the PdfSignatureAppearance.cs method GetAppearance(), more exactly the section between
if (app[2] == null) {
and
}
if (app[3] == null && !acro6Layers) {
This is where iTextSharp creates the default appearance on the PdfTemplate t. Your code may vary only slightly.
Related
I have a Pillow (PIL) image called img. I create a drawing object with drawer = ImageDraw.Draw(img). Now I pass drawer to a function. How can that function see the size of the image? (If I just pass the image, I can get the size easily with img.size)
TL;DR drawer.im.size
The ImageDraw.Draw object has a property called im that can be used to get a ImagingCore object (Note that this is not the usual Image object) which has a size property. Testing it, the size property seems to match that of the original image, so that is what I will use for now.
I am trying to understand the basics behind Pixbuf and its factory methods new_from_data and new_from_stream.
new_from_data requires a string of bytes containing the image data, and other information such as bits per sample, with and height of image.
What I don't understand is why new_from_stream does not require those additional image information. Then, how can the Pixbuf know how to render the image new_from_stream does not provide any additional information other than the Gio.InputStream ?
new_from_stream() expects to get a stream of a supported image file, equivalent to new_from_file(). All the image formats contain metadata like height and width.
new_from_data() on the other hand expects a pixel buffer, which is essentially just an array of pixels without any metadata.
I'm creating a PDF document using iTextSharp, what I'm doing is generating all of my content in a c# List<Chapter> where the Chapters contain one or more Sections, and the Chapters have not yet been added to the document. I then enumerate through my List<Chapter> to generate a table of contents at the start of the document, and then add the Chapters to the document after my TOC.
That works great when my Sections contain text and images, but now I need to generate a Section containing boxes and lines. I don't want to draw my boxes and lines into an image and drop the image into the Section, that won't look as good as if I have actual PDF boxes and lines.
The Sections containing graphical elements can be intermixed with Sections containing text, so I need a way to add some kind of element to a Section such that that graphical Section works like text Sections in terms of going onto a new page only if necessary.
What's the best way to do this? I feel like it somehow involves PdfTemplates but I'm not sure how. Or maybe I need to create a PdfPTable and create my graphical elements in an IPdfPCellEvent?
You are on the right track when you want to involve PdfTemplate elements. PdfTemplate is an iText object that corresponds with the concept of Form XObjects in the PDF specification. We chose another name because the word Form is somewhat misleading (people confuse it with form fields, interactive forms, etc).
The content stream of a page in PDF is a sequence of PDF syntax, consisting of operands and operators. An XObject is an object that is external to this content stream. The content of an XObject is stored inside the PDF document only once, but it can be reused many times on the same page, on different pages.
There are different types of XObjects, but Image XObjects and Form XObjects are the most important ones.
Image XObjects are used when we work with raster images. You are absolutely right when you write: *"I don't want to draw my boxes and lines into an image and drop the image into the Section, that won't look as good as if I have actual PDF boxes and lines."
Form XObjects are used when we want to reuse PDF syntax. This is what you need: you want to define moveTo(), lineTo(), curveTo(), stroke(), fill(),... operations, and you want these lines and shapes to be stored as vector data.
The solution to your problem is to draw lines and shapes to a PdfTemplate object and to wrap the PdfTemplate object inside an Image object. When you add that Image object to a Section or a Chapter, it will be added as a Form XObject. You don't have to feat that it will be degraded into a raster image.
You can find some examples of this technique on the official web site. For instance in the answer to the question
How to generate 2D barcode as vector image?
Here we create a PdfTemplate with a bar code and we return it as an Image object. The screen shot that shows you the internals of the resulting PDF proves that the bar code is added as a vector image.
public Image createBarcode(PdfContentByte cb, String text,
float mh, float mw) throws BadElementException {
BarcodePDF417 pf = new BarcodePDF417();
pf.setText("BarcodePDF417 barcode");
Rectangle size = pf.getBarcodeSize();
PdfTemplate template = cb.createTemplate(
mw * size.getWidth(), mh * size.getHeight());
pf.placeBarcode(template, BaseColor.BLACK, mh, mw);
return Image.getInstance(template);
}
To create a PdfTemplate object, you need a PdfContentByte instance (e.g. using writer.getDirectContent()) and use the createTemplate() method passing a width and a height as parameters. Then you draw content to the PdfTemplate and turn it into an Image object using Image.getInstance().
You'll find more info on drawing lines and shapes in the chapter on Absolute positioning of lines and shapes and in the example section of Chapter 3 and Chapter 14 of my book.
I had a PDF document which has acro text fields which is already shared to the client. Now the client wants to insert signature image in one of the text fields. My manager asked me to try a way to do the same.My idea is to replace an image on top of the text field position and resize the text field as image size.
For replacing acro text field of pdf into image, i am trying as below
1.Finding the text field by its field id
String position = null;
List<FieldPosition> fieldPositons = form.getFieldPositions("50106");
for (FieldPosition position :fieldPositons) {
this.position = position.position;
}
2. Setting the image into that position of text field
Image image = Image.getInstance("ImageFileName");
Float dimensions = position.split("x");
image.setAbsolutePosition(dimensions[0], dimensions[1]);
content.addImage(image);
Based on the given image width and height i need to change the width and height of acro text field.
Can any one tried as below, Is my logic works with itext pdf library. Let me know if any idea to replace acro text field with image
It is never a good idea to change the dimensions of an AcroField as all the content in a PDF is added at absolute positions. When you change the dimension of a field, you risk that it will overlap with other content.
Hence, your best option is to adapt the size of the image to the size of the AcroField. As you already indicated, you can get the field position like this:
AcroFields.FieldPosition f = form.GetFieldPositions("50106")[0];
Note that it's not a good idea to make this a string. You can use the FieldPosition object like this:
int page = f.page;
Rectangle rect = f.position;
You can scale and position the image like this:
Image image = Image.getInstance("ImageFileName");
image.ScaleToFit(rect.Width, rect.Height);
image.SetAbsolutePosition(rect.Left, rect.Bottom);
The ScaleToFit() method will scale the image in such a way that it will fit the dimensions of the form field, respecting the original aspect ratio of the image (you don't want to add a stretched image).
You need to page variable to add the image to the correct page:
PdfContentByte canvas = stamper.GetOverContent(page);
canvas.AddImage(image);
Important:
If you add the image as described above, you need to remove the field (this happens automatically if you flatten the form).
If the form field is a button, then you shouldn't use the above code. Instead you should replace the icon of the button. This is described in my answer to the question How to change a Button Icon of a PDF Formular with itextsharp? This answer explains the standard way to do what you're trying to do, but it requires that the field where you want to add the image is a button field (and based on your question, it seems that it's a text field).
I'm using RaphaelGWT to draw shapes with the underlying RaphaelJS library. Both projects are wonderful. However I was stuck for awhile on the issue of Text objects in Raphael being displayed as centered by default.
I've tried to create one Text object and let it be centered by default, then measure its width in order to adjust the position for a 2nd text object and then remove the first. But I can't get the width of the original Text object.
FYI, in RaphaelGWT, the Shape objects used extend Widget. So I've tried getAbsoluteLeft(), getElement().getAbsoluteRight(), getOffsetWidth(), getElement().getClientWidth(). getAbsoluteLeft() is the only one that returns what I would expect. getAbsoluteRight()returns the same value as getAbsoluteLeft(), and both getOffsetWidth() and getElement().getClientWidth() return 0.
Why?
FYI, I calculated the width from the original x value used to create the Text Shape (x then became the center) and getAbsoluteLeft(), which actually returned the expected value.
The element has to be visible for getOffsetWidth() to return correct values.