adding-drivers-within-an-application.md

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Adding Drivers Within an Application	Adding Drivers Within an Application	cd9bd0a8-652b-440b-a197-81e20a9d71f1	audio compression manager (ACM),adding drivers ACM (audio compression manager),adding drivers ACM examples,adding drivers adding drivers acmDriverAdd function global drivers local drivers audio compression manager (ACM),global drivers ACM (audio compression manager),global drivers audio compression manager (ACM),local drivers ACM (audio compression manager),local drivers	concept-article	4/26/2023	UpdateFrequency5

Adding Drivers Within an Application

[The feature associated with this page, Audio Compression Manager, is a legacy feature. Microsoft strongly recommends that new code does not use this feature.]

If you need your application to implement its own compression routines internally, the application can add drivers to the ACM by calling the acmDriverAdd function. The application implements the driver by providing a function that conforms to the acmDriverProc prototype. After the application has added the driver, the application can use the driver through the ACM as it would use any other driver.

The ACM treats drivers as either global or local. An application specifies whether a driver should be added as global or local when it calls acmDriverAdd. There are two differences between global and local drivers:

• Drivers added as global drivers are not shared with other applications.
• An application can directly alter the priority of a global driver (but not a local driver) by calling the acmDriverPriority function. The ACM conducts a prioritized search when seeking an appropriate driver to provide an implementation of a function call. The ACM always gives local drivers higher priority than global drivers. The most recently added local driver has highest priority.