Annotation and Markup SDK Libraries

LEADTOOLS SDKs include flexible and time-tested document and image annotation libraries for .NET (C#, VB, Core, Xamarin, UWP), C, C++, iOS, macOS, Linux, Java, and web developers. LEADTOOLS libraries include a clean and diverse collection of markup objects and collaborative tools designed to impart visual metadata to digital images and documents, which enhance user experience, productivity, and security. In addition to its award-winning annotation API, LEADTOOLS also supports specialized document and medical annotations for industry standard formats, including PDF and DICOM.

Versatile and robust Annotation and Markup Libraries

Robust Annotation Components

The LEADTOOLS annotation libraries provide APIs and UI controls to add full-color annotation and markup objects to bitonal, grayscale, and color images and documents.

  • Objects can be drawn onto a presentation layer or burned permanently into the image
  • Annotation security APIs provide security to edit annotations and remove redaction objects from private information
  • Many annotation object types are pre-defined, or you can create new custom object types
  • All LEADTOOLS annotation objects can be hyperlinked to show user-defined messages, run applications, or load a web page.
  • Objects can be flipped, reversed, rotated, scaled, sheared, and translated
  • Annotations can be stored in the image file, in a separate annotation file, in a database, or in memory
Annotation libraries to mark up Documents

Document Annotation and Mark up Libraries

LEADTOOLS libraries support several industry standard annotation formats, including PDF, IBM FileNet P8, and Daeja annotations. In addition to the objects that those formats support, the libraries include a broad range of document annotation objects, including redaction, text, geometric shapes, rulers, Bates stamps, audio, and video. The text-based review and collaboration objects are similar to Adobe Acrobat and Microsoft Word. The document can remain searchable, even after it has been marked up or redacted.

  • Underline
  • Strike
  • Highlight
  • Redact
Annotation libraries to mark up PDFs

PDF Annotation Libraries

LEADTOOLS PDF libraries provide APIs to read, display, edit, and write PDF annotations and markups that work seamlessly with Adobe Acrobat and other compliant PDF readers. By annotating and marking up PDF files, users can collaborate by writing comments and drawing shapes on top of the document without making permanent changes. Additionally, sensitive information can be permanently or temporarily redacted to help your application comply with standards such as GDPR and HIPPA.

The LEADTOOLS PDF libraries provide APIs to load, view, edit, create, and save the following PDF annotations:

  • Arrow
  • Highlight
  • Intent
  • Leader
  • Line
  • Line Endings
  • Redaction
  • Review
  • Shapes
  • Text
  • Text Callout
  • Note reply
  • Transformation
  • Comments and replies
Annotation libraries for DICOM images

DICOM and Medical Imaging Annotation Libraries

A broad range of DICOM and medical image annotation objects are included in the Medical Image Viewer and Medical Workstation Viewer controls. These medical image annotations can be added to DICOM, bitonal, color, and grayscale images, either on a presentation layer or burned into the image data. They are perfect for highlighting areas of interest and redacting private information. Access to edit annotations or view private information can be control with user-level passwords. Flexible annotation object storage options include DICOM data sets (Grayscale Softcopy Presentation State), image files, separate annotation files, database, memory, and XML.

  • Audio
  • Video
  • Cross Product
  • Encryption
  • Freehand
  • Pointer
  • Polyruler
  • Protractor
  • Redaction
  • Ruler
  • Text
  • Text Pointer
Feature-rich Annotation and Markup SDK

Annotate Images in HTML5 and JavaScript Apps

The LEADTOOLS annotations library for HTML5 and JavaScript is a powerful framework that adds the full power of LEADTOOLS desktop annotations to many browsers and devices.

Check out the live demos to see the HTML5 annotations in action.

Provide privacy and security with Annotation and Markup Libraries

Implement Annotation Security for Each and Every Object

The annotation security APIs provide security to edit annotations and remove redaction objects to gain access to private information. Enhanced redaction objects hide and encrypt confidential parts of images and documents even in non-LEADTOOLS viewers. When combined with annotation security, these redact objects provide a means of granting user-level access to view redacted areas of an image or document.

Versatile and robust Annotation and Markup Libraries

Versatile Storage of Annotations

LEADTOOLS annotations can be stored as an external annotation file, XML, private DICOM data elements, within a TIFF file as LEAD or Wang annotation tags, or in PDF documents as native PDF annotations. Alternatively, annotations can become a permanent part of the data or exported as SVG or EMF.

Programmer friendly Annotation and Markup Libraries

Ease of Use and Control

The simplicity of using LEADTOOLS annotations is extended to both the developer and the end-user. With very little code, the developer can create a fully automated, dynamic, and feature-packed annotation application, which is also easy to operate by the end-user. Automation features include mouse event handling, cursors, toolbars, right-click context menus, and instant text editing.

With the LEADTOOLS Annotation Customizable Features, developers can create new annotation types, change the context menus and toolbars, and localize the dialog strings. End-users can rotate, calibrate, and change virtually any visual setting of the annotations on the screen.

Cross platform libraries

Annotation and Markup SDK Platforms and Programming Interfaces

Projects that use LEADTOOLS Annotation and Markup libraries can be deployed to web browsers, Windows, macOS, iOS, Android, and Linux devices.

Annotation and Markup SDK libraries are available for

The following are some examples of web browsers that support HTML5 markup:
  • Desktop Browsers
    • Chrome
    • Firefox
    • Edge
    • Internet Explorer 9 and later
    • Opera
    • Safari
  • Mobile and Tablet Browsers
    • Safari
    • Chrome
    • Edge
    • Internet Explorer 10 and later
    • Android
    • Firefox Mobile
    • Opera Mobile

Start Coding With LEADTOOLS Annotation and Markup


Annotation and Markup libraries for Windows, Linux, and macOS as well as all LEADTOOLS Recognition, Document, Medical, Vector, and Imaging technologies for all development and target platforms.

Download LEADTOOLS Libraries

Online Demo Applications that include Annotation and Markup SDK Libraries

HTML5/JavaScript Annotations

Uses LEADTOOLS annotations and image-markup libraries to add stamps, sticky notes, rulers, and various other image markup devices to an annotation layer of the image without changing the original image data.

  • Draw annotations
  • Export image

HTML5/JavaScript Medical Web Viewer Framework

A zero-footprint Medical viewer with light and dark themes to display DICOM images (pixel data) with window level, density removal, offset, scale, zoom, stack, annotation/markup, and multi-touch support for phone, tablet, and desktop.

It demonstrates zero-footprint 3D volume rendering of multiple volume types including VRT, MIP, MPR, and SSD in the Medical Web Viewer. The viewer does not require browser plugins, desktop utilities, or remote desktop clients and options for low-resolution and caching to speed up rendering and loading.

Note: If you have your own test images that you would like to upload into the application, contact support@leadtools.com to have a private user profile created.

HTML5/JavaScript Dental Web Viewer Framework

The zero-footprint Medical Web Viewer with specialized dental features enabled, including Endo, Perio, Dentin, and FMX layouts. Additionally shows multi-touch support for phone, tablet, and desktop.

  • Interactive brightness and contrast display
  • Display DICOM information

Mobile Demo App

Use the LEADTOOLS Annotations App to annotate (mark-up) images without changing the image data. Add many annotation object types.