DxApi Miniport Driver Functions For Windows 2000 and Later
Supporting the DxApi interface in a video miniport driver is only supported with Windows 2000 and later.
DxApi interface support is useful for the following operations:
Autoflipping using an IRQ for devices that do not support hardware autoflipping or that have limitations that make it undependable. This allows DirectDraw to always revert to software autoflipping when hardware autoflipping is unavailable.
Field skipping using an IRQ to support MPEG drivers that can undo the 3:2 pulldown of MPEG data originally sampled from film.
Capturing video and VBI. In the miniport driver, it is easy to capture video that is based on a hardware video port IRQ or graphics IRQ.