GdPicture components offer superior support for image acquisition from scanners, capture cards and digital cameras using TWAIN protocol in 32-bit and 64-bit modes.

With just a few lines of code, you will be able to start a single or a multiple image acquisition process using any TWAIN-compliant device, edit and save scanned documents to any destination such as a local/network machine, FTP site, web server, or database.

Intuitive low-level & high-level API are provided under .NET components and TWAIN ActiveX to let you negotiate all TWAIN 2.3 capabilities from any kind of WinFormWPF or Web application.

Looking for cross browser-based document scanning support?

Our web toolkit DocuVieware provides all the necessary components to scan, edit, and save documents online. Check the live demo!

Illustration of TWAIN Logo

TWAIN scanning

The acquisition process requires three items: a scanner, a driver, and software. Drivers are the bridges that let the software communicate with the device through standardized APIs. TWAIN is an industry-standard API for image acquisition, strongly oriented toward scanners. Of the four different scanning protocols, TWAIN is the most widely adopted by the market. Supported by most operating systems (Windows, Mac OS, Linux/Unix), the protocol defines a set of options like resolution, color, scanning areas for flatbed scanners, and more. The TWAIN Working Group develops and maintains TWAIN since 1992.

Main TWAIN features of the SDK

GdPicture - Twain SDK

*If you have problems using CITRIX, please look at the following knowledge base articles:


Reliable technology

Reliable technology

API built on top of the best document imaging SDK in the market, taking benefit of more than 15 years of continuous research focused on innovation. Support for unstable TWAIN drivers thanks to continuous device diagnosing.

Reduced Time to Market

Reduced Time to Market

Add the advanced post processing features provided by the GdPicture.NET toolkit to your scanning application: PDF, OCR, formats conversion & document imaging SDK. Reduce the learning curve by using the same technology on different platforms.

Continuous Development and Delivery

Continuous Development and Delivery

To provide you with the latest technologies and an always up-to-date SDK, we publish weekly releases. Check our version history page and subscribe to our developer newsletter to learn more about the new features and improvements.

Universal scanning SDK

Universal scanning SDK

GdPicture.NET scanning SDK is compatible with the two most used scanning protocols, TWAIN and WIA. Acquisition from all types of scanner devices and digital cameras is possible with support for both 32 and 64bits.

Web scanning SDK with DocuVieware

How to use the live demo?

TWAIN acquisition can be made from the dedicated snap-in or a dialog window triggered by a dedicated toolbar button.

When launching DocuVieware for the first time, the viewer will require the installation of a small software to connect to the TWAIN devices. It is a one-time step, and once it has been installed, it is silently started with Windows.

DocuVieware will then be able to trigger the device driver window so you can choose the acquisition settings you need.

Learn more about TWAIN web-scanning on the DocuVieware website.


When should I used WIA over TWAIN?

WIA (Microsoft Windows Image Acquisition) API is standardized for acquiring digital images from devices that are primarily used to capture still images and for managing these devices. WIA is a COM interface, very different from but overlapping with TWAIN.

Compared to TWAIN, WIA offers much better support for digital cameras and much less sophisticated support for scanners.

There are a few other parameters to keep in mind:

Check our WIA scanning page for more features and functionalities.

Are there other scanning protocols?

There are four scanning protocols currently used by the market:

Here is a chart that synthesizes the different features of each protocol:

Adoption by the marketvery highhighlowlow
Developed byTWAIN Working GroupMicrosoftPixel Translations (then EMC Corporation’s Captiva Software). Now owned by OpenTextSANE open-source project
Digital camera supporthighvery highlowvery low
Supported OSWindows, Mac OS, Linux/UnixWindowsWindowsLinux/Unix
LicensingLGPL (Data Source Manager only) – freeproprietary – freeproprietary – commercialopen source
SpecificationTWAIN specificationWIA specificationISIS specificationSANE specification

I want to test your library, but I don’t have a scanner

If you don’t have a physical TWAIN scanner to test the SDK, you can download and use a virtual scanner (32 & 64-bit) here.

How to use

Download and install GdPicture.NET package from here.

Check our other Scanning technologies

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