.NET API for Watermark Manipulation

Build .NET Applications to Operate Text & Image Based Watermarks with Smart Search & Strong Security Features.

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.NET Watermark API

GroupDocs.Watermark for .NET


GroupDocs.Watermark for .NET enables you to build ready-to-market business applications in C#, ASP.NET and other .NET related technologies, which let your end-users, add new watermarks, search and remove existing watermarks in supported file formats. Using GroupDocs.Watermark for .NET, you can programmatically apply digital watermarks to multitude of file formats and discourage unauthorized use of intellectual property and securely label documents of sensitive nature by employing various built-in security measures offered by this API.


GroupDocs.Watermark for .NET Features



Add or Remove Watermarks from a Particular Section or whole Document of Various File Formats


Attach Watermark to all Images in a Particular Section, Page, Slide, or Document


Assign Watermark to only Particular Frames of a Multi-Framed Image


Allocate Hidden Watermark to PDF that only Appears when Printing Document


Set Watermark to all Attachments in an Excel Document & all Image Shapes in Slides


Place Watermark or Remove it from the Background Images of Spreadsheet or Slides


Employ Watermark to Supported Files in all Attachments of an Email or PDF Document


Apply or Remove Watermark as XObjects, Artifacts & Annotations in PDF Documents


Eliminate Watermark Containing Text with Particular Formatting


Look for Image Watermarks that Resemble a Particular Image


Identify Text Watermark Even if there are Unreadable Characters between Letters


Search Watermarks Based on Specific Parameters or by Combining Multiple Criteria


Specify Font Formatting to Look for Matching Text Watermark


Programmatically Extract Page Setup & Other Information for Supported Formats


Add Watermark to Images inside any Header & Footer in Supported Document Formats


Add Watermark to Image Shapes in a Word Document & Lock Watermarks to Restrict Editing


Protect Text Watermark using Unreadable Characters in Presentations


Rasterize Particular Page or Whole PDF Document to Protect Added Watermarks


Change Text Formatting While Replacing Existing Text Watermark


Align Watermark to Bleed Box, Art Box, Crop Box, or Trim Box in PDF Document


Edit Shape Properties in Microsoft Visio Documents

Adding Watermarks

GroupDocs.Watermark for .NET supports multiple types of watermarks. Adding watermarks of any type is only a matter of few lines of code. Following example demonstrates, applying an image watermark to Word document using C#:

Applying Image Watermark using C#

// Load the document
using (FileStream stream = File.Open("document.docx", FileMode.Open, FileAccess.ReadWrite))
	using (Watermarker watermarker = new(Watermarker(stream))
       		 // Use path to the image as constructor's parameter
       		using (ImageWatermark watermark = new ImageWatermark("logo.png"))
			watermark.HorizontalAlignment = HorizontalAlignment.Center;
			watermark.VerticalAlignment = VerticalAlignment.Center;
			 // Save the resultant document

Apply Watermark to Files of Different Formats in a Go

GroupDocs.Watermark API allows you to apply watermark or delete watermark of all files in a specific folder in one go. The files can even be of different format and yet the watermark will be applied to all of them accurately.

Foolproof Security for Watermark

With only one line of code you can make it very difficult for any tool to remove your watermark from PDF files. This is achieved by converting all pages of a PDF document to raster images while keeping the original quality intact.


Support and Learning Resources


GroupDocs.Watermark offers document watermarking APIs for other popular development environments as listed below: