 |
 |
|
|
|
 |
|
The
Whys and the Wherefores of the New Windows Driver Standard Page 1, 2 |
|
||||||||
| Direct
Sound Direct Sound is the audio component of DirectX, and adds hardware acceleration and direct access from the program to the audio device within the Windows system. Direct Sound compatibility could be added to VXD drivers for Win 95/98. When Direct Sound was not or could not be added to a device driver, Windows would create an emulation mode so that the driver could at least work with an application that required Direct Sound compatibility, though performance was compromised. DirectX support was added to Windows NT in Service Pack 3 and beyond, but has always been limited to version 3 (the latest DirectX version is DirectX 8.0). Still, Direct Sound only works in Windows NT in emulation mode. DirectX compatibility is built into the WDM driver. This creates a fundamental and major difference between the NT driver and the Win 2000 (WDM) driver, and greatly enhanced performance in the WDM driver over a Windows 98 driver with added-on DirectX (i.e., Direct Sound) compatibility. Again, due to the streamlined nature of the WDM driver model, Direct Sound support is achieved without the addition of driver code, in this case the DirectX APIs, or, "application programming interfaces." WDM and You! The end result is a more efficient, streamlined driver for the end-user with far fewer timing issues for the streaming media enthusiast, including synchronization between the application and the hardware and system latency that has always been a problem in the Windows system. For the hardware manufacturer, investments in driver development can extend into the hundreds of thousands of dollars. While the transition to the single use of the WDM model may be initially troubled by legacy support of Windows 95 (and of course continued VXD driver support for Win 98 while WDM drivers are in development), it would not be unreasonable for manufacturers to soon end support of Win 95. While the WDM model should afford a seamless transition between Windows 2000 and Windows XP (and future Windows operating systems), future needs and tweaks should never result in the need to rebuild or build a new driver. Should you upgrade your driver to WDM? If you're a Win 98 or ME user, first check with the hardware manufacturer to see if a WDM driver exists or is in development. Also check with your software manufacturer to see if your program can benefit from the use of a WDM driver with your particular capture device. If you're a Windows 2000 user, it is most likely a necessity that you use a WDM driver. Theoretically, an NT driver will work in Win 2000, but in actuality there were problems for streaming media capture and playback. Your manufacturer should have WDM drivers, but if not, some gentle lobbying is in order. JD Mars is the producer of Digital Pro Sound, a multi-platform/multi-OS kind of guy, and aspiring to be bi-coastal. |
|||||||||
|
