Windows Image Acquisition
Encyclopedia
Windows Image Acquisition (WIA; sometimes also called Windows Imaging Architecture)
is a Microsoft
driver model and application programming interface
(API) for Microsoft Windows
Me and later Windows operating systems that enables graphics software to communicate with imaging hardware such as scanner
s, digital camera
s and Digital Video
-equipment. It was first introduced in 2000 as part of Windows Me
, and continues to be the standard imaging device and API model through successive Windows versions. It is implemented as an on-demand service in Windows XP
and later Windows operating systems.
. Whereas STI only provided a low-level interface for doing basic transfers of data to and from the device (as well as the invocation of an image scan process on the Windows machine through the external device), WIA provides a framework through which a device can present its unique capabilities to the operating system, and applications can invoke those features.
According to Microsoft, WIA drivers are made up of a user interface (UI) component and a driver core component, loaded into two different process spaces: UI in the application space and the driver core in the WIA service space.
It is said to be more flexible than TWAIN
because it is a standardized interface that doesn't require a tight bundling of scanner software and driver (TWAIN-only scanners are often limited to functions that are enabled in its driver software bundle). Most recent scanners support WIA.
In Windows XP, WIA runs in the LocalSystem context. Because of the security ramifications of running a service as LocalSystem whereby a buggy driver or malicious person would have unrestricted access to the system, the WIA service in Windows Server 2003
and Windows Vista
operates in the LocalService context. This can result in compatibility issues when using a driver designed for Windows XP.
In Windows XP, support was added for Automatic document feeder
scanners, scroll-fed scanners without preview capabilities and multi-page TIFF generation. For WIA video, a Snapshot filter driver is introduced which allows still frames to be captured from the video stream.
Windows Vista
has the WIA Automation library built-in. Also, WIA supports push scanning and multi-image scanning. Push scanning allows initiating scans and adjusting scanning parameters directly from the scanner control panel. Multi-image scanning allows you to scan several images at once and save them directly as separate files. However, video content support is removed from WIA for Windows Vista. Microsoft recommends using the newer Windows Portable Devices API.
is a Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
driver model and application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
(API) for Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
Me and later Windows operating systems that enables graphics software to communicate with imaging hardware such as scanner
Image scanner
In computing, an image scanner—often abbreviated to just scanner—is a device that optically scans images, printed text, handwriting, or an object, and converts it to a digital image. Common examples found in offices are variations of the desktop scanner where the document is placed on a glass...
s, digital camera
Digital camera
A digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...
s and Digital Video
Digital video
Digital video is a type of digital recording system that works by using a digital rather than an analog video signal.The terms camera, video camera, and camcorder are used interchangeably in this article.- History :...
-equipment. It was first introduced in 2000 as part of Windows Me
Windows Me
Windows Millennium Edition, or Windows Me , is a graphical operating system released on September 14, 2000 by Microsoft, and was the last operating system released in the Windows 9x series. Support for Windows Me ended on July 11, 2006....
, and continues to be the standard imaging device and API model through successive Windows versions. It is implemented as an on-demand service in Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
and later Windows operating systems.
Overview
WIA is a significant superset of the support for digital still imaging drivers that was provided by the Still Image Architecture (STI) in Windows 98Windows 98
Windows 98 is a graphical operating system by Microsoft. It is the second major release in the Windows 9x line of operating systems. It was released to manufacturing on 15 May 1998 and to retail on 25 June 1998. Windows 98 is the successor to Windows 95. Like its predecessor, it is a hybrid...
. Whereas STI only provided a low-level interface for doing basic transfers of data to and from the device (as well as the invocation of an image scan process on the Windows machine through the external device), WIA provides a framework through which a device can present its unique capabilities to the operating system, and applications can invoke those features.
According to Microsoft, WIA drivers are made up of a user interface (UI) component and a driver core component, loaded into two different process spaces: UI in the application space and the driver core in the WIA service space.
It is said to be more flexible than TWAIN
TWAIN
TWAIN is a standard software protocol and applications programming interface that regulates communication between software applications and imaging devices such as scanners and digital cameras....
because it is a standardized interface that doesn't require a tight bundling of scanner software and driver (TWAIN-only scanners are often limited to functions that are enabled in its driver software bundle). Most recent scanners support WIA.
Additional information
In 2002, Microsoft released the Windows Image Acquisition Automation Library Tool, which provides access to WIA functionality through programming languages and scripting environments that support OLE Automation.In Windows XP, WIA runs in the LocalSystem context. Because of the security ramifications of running a service as LocalSystem whereby a buggy driver or malicious person would have unrestricted access to the system, the WIA service in Windows Server 2003
Windows Server 2003
Windows Server 2003 is a server operating system produced by Microsoft, introduced on 24 April 2003. An updated version, Windows Server 2003 R2, was released to manufacturing on 6 December 2005...
and Windows Vista
Windows Vista
Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
operates in the LocalService context. This can result in compatibility issues when using a driver designed for Windows XP.
In Windows XP, support was added for Automatic document feeder
Automatic Document Feeder
In multifunction or all-in-one printers, fax machines, photocopiers and scanners, an automatic document feeder or ADF is a feature which takes several pages and feeds the paper one page at a time into a scanner or copier, allowing the user to scan, and thereby copy, print, or fax, multiple-page...
scanners, scroll-fed scanners without preview capabilities and multi-page TIFF generation. For WIA video, a Snapshot filter driver is introduced which allows still frames to be captured from the video stream.
Windows Vista
Windows Vista
Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
has the WIA Automation library built-in. Also, WIA supports push scanning and multi-image scanning. Push scanning allows initiating scans and adjusting scanning parameters directly from the scanner control panel. Multi-image scanning allows you to scan several images at once and save them directly as separate files. However, video content support is removed from WIA for Windows Vista. Microsoft recommends using the newer Windows Portable Devices API.
Applications that use WIA
- Photoshop
- Paint.NETPaint.NETPaint.NET is a proprietary freeware raster graphics editor program for Microsoft Windows, developed on the .NET Framework. Originally created by Rick Brewster as a Washington State University student project, Paint.NET has evolved from a simple replacement for the Microsoft Paint program, which is...
- ACDSeeACDSeeACDSee is a shareware image organizer, viewer, and editor software for Microsoft Windows and Mac OS X 10.5 and higher developed by ACD Systems. It was originally distributed as a 16-bit application for Windows 3.0 and later supplanted by a 32-bit version for Windows 95.ACDSee displays a tree view...
- Windows Scanner and Camera Wizard
See also
- Image and Scanner Interface Specification (ISIS)
- Standard for image acquisition devices (TWAIN)TWAINTWAIN is a standard software protocol and applications programming interface that regulates communication between software applications and imaging devices such as scanners and digital cameras....
- Scanner Access Now Easy (SANE)Scanner Access Now EasyScanner Access Now Easy is an application programming interface that provides standardized access to any raster image scanner hardware ....
External links
- List of Scanners That Are Supported by Windows Image Acquisition
- List of Digital Cameras That Are Supported by Windows Image Acquisition
- Windows Image Acquisition (WIA): MSDN
- Still Image Connectivity for Windows — describes WIA and compares it to Picture Transfer ProtocolPicture Transfer ProtocolPicture Transfer Protocol is a widely supported protocol developed by the International Imaging Industry Association to allow the transfer of images from digital cameras to computers and other peripheral devices without the need of additional device drivers...
and USB Mass Storage methods for transferring images between a digital imaging devices and the computer. - Sample code creating a WIA utility class on codeproject.com