This article provides an overview of the hardware support features provided by Windows XP, that enhance the usability of your personal computer.
Device and hardware support has been improved in many ways for the Microsoft® Windows® XP operating system for greater system stability and device compatibility. It includes Plug and Play support for hundreds of devices not covered by Windows 2000, and enhanced support for Universal Serial Bus (USB), IEEE 1394, Peripheral Component Interconnect (PCI), and other buses.
Windows Image Acquisition (WIA) provides robust communication between applications and image-capture devices, allowing you to capture images efficiently and transfer them to your computer for editing and use. WIA supports Small Computer System Interface (SCSI), IEEE 1394, USB, and serial digital still image devices. Support for infrared, parallel, and serial still-image devices, which are connected to standard COM ports, comes from the existing infrared, parallel, and serial interfaces.
WIA architecture is both an Application-Programming Interface (API) and a Device Driver Interface (DDI).
Scanner and Camera Wizard: Using this wizard, you can retrieve images from any of the WIA-enabled devices installed on the system. The wizard provides a preview page, where you can select from several scanning options and adjust image settings.
Windows Explorer User Interface (UI): Windows Explorer extensions such as My Computer and My Pictures, in addition to Scanners and Cameras in Control Panel, provide an interface with which you can access WIA devices. It also provides the option of e-mailing a picture, ordering prints over the Internet, posting pictures to a web site, and saving pictures to CD-R and CD-R/W media (see below for further discussion of Windows XP CD mastering technologies).
WIA applications: There are two main types of WIA applications: image editing applications, such as Adobe Photoshop and Microsoft Picture It!®; and applications for authoring documents that include image data, but cannot edit image data, such as Microsoft Word and the Microsoft PowerPoint® presentation graphics program.
Class Installer: The Imaging Class Installer is a WIA component used by Windows Plug and Play to support easy installation and removal of WIA devices. The installer also supports Plug and Play devices for USB, SCSI, IEEE 1394 buses, and serial-based digital still cameras.
Scripting interface: WIA includes a scripting interface, which allows advanced users and IT professionals to develop WIA applications using the Microsoft Visual Basic® development system and other scripting languages.
TWAIN Data Source Manager and compatibility driver: The TWAIN Data Source Manager (DSM) is an industry-standard software library used to abstract TWAIN applications from still image devices. WIA uses the TWAIN DSM implementation in Windows XP, together with the TWAIN compatibility driver to provide a compatibility layer for applications that support TWAIN version 1.7 or later, but don’t yet support WIA.
Common system dialog objects: All scanner and camera device drivers that ship in Windows XP use the WIA common system dialog objects. There are four system dialog objects: the scanner common dialog object, the still camera common dialog object, the video camera common dialog object, and the device selection dialog object. Represented in the UI as dialog boxes, these allow you to preview thumbnails and full-sized pictures; crop, scan, and set scan properties of a picture; view picture information; view live or recorded digital video and capture frames from the stream; select WIA devices; and set their properties.
Device object: When the WIA device driver is started, it creates a system component called the device object. There are four types of device objects: mini driver, generic flatbed scanner, generic digital still camera, and generic video camera object.
WIA Device Manager: When an application first communicates with a device, the WIA Device Manager detects all the devices, creates the device objects, establishes the link between the application and the device objects, and retrieves and sets device properties.
Digital Audio Devices and Technologies
To support digital audio devices, Windows XP uses the Windows Driver Model (WDM) audio architecture, which enables the operating system to manage multiple audio streams simultaneously. Windows XP includes several new technologies designed to enhance digital audio playback and recording, such as:
-Multi-channel audio output and playback of additional audio formats. Volume can be set for each speaker in a multi-channel configuration.
-Acoustic Echo Cancellation (AEC), a signal processing feature that reduces feedback, echo, and other ambient noise from input channel. USB microphones in particular benefit from this technology.
-Global Effects (GFX), which enhances USB audio support by allowing filter drivers to support devices such as USB array microphones
Supporting New Hardware Technologies
Windows XP also supports many new hardware technologies including:
-Expanded PS/2 and USB interface keyboards, which have additional keys for multimedia functions, web browsing, power management, and/or other functions.
-New audio/visual (A/V) devices are using the IEEE 1394 interface such as digital VHS recorders.
-New USB array microphones (of the type used in conferencing applications and Internet telephony) that mix audio streams through kernel-mode Global Effects (GFX).
-Wireless networking devices, in particular two adapters from Sierra: the AirCard 300, which enables 19.2 kilobits per second (Kbps) Internet connections, wherever digital cell phone service is available; and the AirCard 400, which enables 128 Kbps connections in cities served by the new Ricochet network.
-Support for high-resolution monitors built to display up to 200 dots per inch (dpi).