PDF Add Watermark

PDF Add Watermark

Type: pdf-add-watermark  ·  Package: PDF Activities v1.2.4  ·  Output: string

Adds a diagonal text watermark to every page of a PDF, and saves the result in a new file. Useful to mark documents as “COPY”, “CONFIDENTIAL”, “DRAFT” or with the recipient’s name.

How it works

Draws text centred on each page, on top of the content, in Arial bold, with the given opacity, size, colour and angle, and creates a new PDF at output. Returns the path of the file created. The original stays intact.

• The text is a single line: if it is too long for the chosen size, it runs off the page. Lower fontSize for long texts.
• opacity, fontSize and angle accept a number or an expression (e.g. Config["Opacity"]). Since 1.2.4. A value that isn’t a number is an error, as is an opacity outside 0–1 or a fontSize of 0 or less.
• A color other than the three supported ones uses grey.
• It creates the output folder if it doesn’t exist and overwrites the file if it already exists.

Required parameters

Parameter	Type	Default	Description
path	string	—	Path of the source PDF.
output	string	—	Path of the resulting PDF.
text	string	—	Watermark text. It accepts expressions (e.g. the recipient’s name).

Optional parameters

Parameter	Type	Default	Description
opacity	number	0.3	Opacity from 0.0 (invisible) to 1.0 (opaque).
fontSize	number	48	Font size in points.
color	string	"gray"	Colour: gray · red · blue.
angle	number	45	Rotation angle in degrees, counter-clockwise (0 = horizontal).

Output

Returns a string with the path of the PDF created (the same as output).

Common errors

Message	Cause and fix
'opacity' must be a number. Received: …. (or 'fontSize', 'angle')	The typed value or the result of the expression isn’t a number. Since 1.2.4.
'opacity' must be between 0 and 1. Received: ….	Opacity out of range; use 0.5, not 50. Since 1.2.4.
'fontSize' must be greater than 0. Received: ….	Font size 0 or negative. Since 1.2.4.
File not found.	The path doesn’t exist.
'path' is required. / 'output' is required. / 'text' is required.	The parameter was left empty or its expression returned null.
PDF library error when opening the file	Password-protected or damaged PDF. See Protected and damaged PDFs.

Example

Mark each copy with the recipient’s name:

PDF Add Watermark
  path    = contractPath
  output  = "C:/copies/" + customer.name + ".pdf"
  text    = "COPY — " + customer.name
  opacity = 0.2
  color   = red
  → output: copy
Log   message = "Copy generated: " + copy

Related activities

• PDF Create — create a PDF from scratch.
• PDF Merge — combine documents.