Magnifier (Windows)
Encyclopedia
Magnifier is a screen magnifier
program for the visually impaired to use Microsoft Windows
. When it is run, it creates a bar at the top of the screen that greatly magnifies where the mouse is. Magnifier was first included as a sample in the Active Accessibility
SDK/RDK for Windows 95
and later made a standard Windows utility starting with Windows 98
. Prior to Windows Vista, Magnifier could be used to magnify the screen up to 9 times its normal size. Windows Vista and later allow up to 16× magnification
.
In Windows Vista
, Magnifier uses WPF
, which in turn uses vector images to render the content. As a result, the rendered magnified image is sharp and not pixelated. However, this is useful only for Windows Presentation Foundation
applications. Non-WPF applications are still magnified the traditional way. Also, due to a change introduced in WPF 3.5 SP1, this functionality is lost if .NET Framework 3.5 SP1 is installed.
Microsoft has also released a Magnification API to allow assistive technology applications to use the Magnifier engine.
Microsoft's Windows 7 operating system includes a significantly improved version of Magnifier. It features full-screen magnification which allows a user to pan around the screen at up to 16× magnification.
However, the full screen feature has also been criticized due to its incompatibility with the high contrast color schemes found in the Windows 7 beta release. This issue remains in the final Windows 7 release. Besides this, when the magnifier zooms, the text will get blurry due to the anti-aliased fonts the operating system is using since Vista. There are some options to disable the anti-aliased (glassy) fonts to some level, but this will result in a blocky image. This problem is solved by other (third party) magnification software developers by adding text smoothing/enhancement functionality, which Windows 7 Magnifier lacks in the final release.
The magnifier also features a lens mode similar to that found in the existing version of the software. Lens mode is improved, however, as now the magnifying window will follow the cursor around the screen rather than remain in a fixed position. Finally the magnifier is much easier to access by using the Windows Key and +/- to control the zoom level without the need to start the application first.. Pressing the Win+Esc combination will exit the magnifier.
Screen magnifier
A screen magnifier is software that interfaces with a computer's graphical output to present enlarged screen content. It is a type of assistive technology suitable for visually impaired people with some functional vision; visually impaired people with little or no functional vision usually use a...
program for the visually impaired to use 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...
. When it is run, it creates a bar at the top of the screen that greatly magnifies where the mouse is. Magnifier was first included as a sample in the Active Accessibility
Microsoft Active Accessibility
Microsoft Active Accessibility is an Application Programming Interface for user interface accessibility. MSAA was introduced as a platform add-on to Microsoft Windows 95 in 1997...
SDK/RDK for Windows 95
Windows 95
Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 by Microsoft, and was a significant progression from the company's previous Windows products...
and later made a standard Windows utility starting with Windows 98
Windows 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...
. Prior to Windows Vista, Magnifier could be used to magnify the screen up to 9 times its normal size. Windows Vista and later allow up to 16× magnification
Magnification
Magnification is the process of enlarging something only in appearance, not in physical size. This enlargement is quantified by a calculated number also called "magnification"...
.
In 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...
, Magnifier uses WPF
Windows Presentation Foundation
Developed by Microsoft, the Windows Presentation Foundation is a computer-software graphical subsystem for rendering user interfaces in Windows-based applications. WPF, previously known as "Avalon", was initially released as part of .NET Framework 3.0. Rather than relying on the older GDI...
, which in turn uses vector images to render the content. As a result, the rendered magnified image is sharp and not pixelated. However, this is useful only for Windows Presentation Foundation
Windows Presentation Foundation
Developed by Microsoft, the Windows Presentation Foundation is a computer-software graphical subsystem for rendering user interfaces in Windows-based applications. WPF, previously known as "Avalon", was initially released as part of .NET Framework 3.0. Rather than relying on the older GDI...
applications. Non-WPF applications are still magnified the traditional way. Also, due to a change introduced in WPF 3.5 SP1, this functionality is lost if .NET Framework 3.5 SP1 is installed.
Microsoft has also released a Magnification API to allow assistive technology applications to use the Magnifier engine.
Microsoft's Windows 7 operating system includes a significantly improved version of Magnifier. It features full-screen magnification which allows a user to pan around the screen at up to 16× magnification.
However, the full screen feature has also been criticized due to its incompatibility with the high contrast color schemes found in the Windows 7 beta release. This issue remains in the final Windows 7 release. Besides this, when the magnifier zooms, the text will get blurry due to the anti-aliased fonts the operating system is using since Vista. There are some options to disable the anti-aliased (glassy) fonts to some level, but this will result in a blocky image. This problem is solved by other (third party) magnification software developers by adding text smoothing/enhancement functionality, which Windows 7 Magnifier lacks in the final release.
The magnifier also features a lens mode similar to that found in the existing version of the software. Lens mode is improved, however, as now the magnifying window will follow the cursor around the screen rather than remain in a fixed position. Finally the magnifier is much easier to access by using the Windows Key and +/- to control the zoom level without the need to start the application first.. Pressing the Win+Esc combination will exit the magnifier.