PDF Annotations in C# .NET

GdPicture.NET SDK simplifies the management and manipulation of annotations within PDF documents. In addition, the custom-designed XMP annotations, based on the XML syntax, allow you to add annotations to images and TIFF files. The SDK provides you with a comprehensive set of tools and libraries to create, edit, and extract annotations, allowing for seamless integration of annotation functionality into your applications.

Key Capabilities

Create, Edit, Remove

Create various types of annotations, such as text comments, highlights, underlines, circles, rectangles, and more

Edit Annotations

Modify and manipulate existing annotations within PDF documents — this includes updating annotation properties like color, size, opacity, and position, as well as resizing, moving, and deleting annotations

Attach Files and Images

Add files and images to annotations

Annotate on Images

Annotate on images and TIFF files using our custom XMP annotations

Data Import and Export

Extract annotations from PDF documents and import the annotation data, making it possible to retrieve and work with annotations separately

PDF Actions Support

Assign PDF actions to annotations


Embed annotations in the PDF structure

What Are Annotations?

Content displayed as a PDF page isn’t suitable for easy editing, but the PDF specification defines a comprehensive set of objects that can be added to PDF pages without changing the page content. These objects are called annotations, and their purpose ranges from marking up page content to implementing interactive features such as forms.

Essential Guides

Import and Export

Create Annotations

Edit Annotations

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