reactos/drivers/multimedia

This is a directory for the kernel streaming components, along with multimedia
kernel-mode drivers.

Much of this code exists only as stubs for future implementation.

The "include" directory exists as a place to store the KS related headers. It
should be moved to the main include tree later.

Andrew Greenwood
3rd December, 2006


== Kernel Streaming (KS.SYS) ==

Deals with streaming media. This is the core component for this, and can be
interacted with from usermode (usually via DirectX.)

XP and DirectX 8 versions of this component provide an additional suite of
AvStream API functions.

COM-style interfaces are used with this component.


== SysAudio (SYSAUDIO.SYS) ==

Filter graph builder (deals with topology.) Not sure what this does yet.


== Port Class (PORTCLS.SYS) ==

Used by WDM audio drivers, this handles many common tasks required for
audio drivers.

COM-style interfaces are used with this component.


== WDM Audio (WDMAUD.DLL / WDMAUD.SYS) ==

Effectively a relay from usermode to kernelmode, the usermode portion is a
MME-style driver (for WINMM.DLL) which tells the kernelmode portion what to do.

This typically involves interacting with KS.SYS in some way.

In Vista, the kernelmode portion is no longer present and the usermode portion
interacts with the Vista audio stack (which resides in usermode but also
ultimately ends up going back into kernelmode in the end!)


== Optional drivers ==

- sndblst	Sound Blaster (+ Pro / 16) compatible driver
- mpu401	MPU-401 MIDI compatible driver