DirectMusic

DirectMusic is a deprecated component of the Microsoft DirectX API that allows music and sound effects to be composed and played and provides flexible interactive control over the way they are played. Architecturally, DirectMusic is a high-level set of objects, built on top of DirectSound, that allow you to play sound and music without needing to get quite as low-level as DirectSound. DirectSound allows for the capture and playback of digital sound samples, whereas DirectMusic works with message-based musical data. Music can be synthesized either in hardware, in the Microsoft GS Wavetable SW Synth, or in a custom synthesizer.

DirectMusic was first released by Microsoft in 1996 as an ActiveX control called Interactive Music Architecture (IMA). It was introduced as part of the 6.1 version of the DirectX library in February 1999 and is included in all Microsoft Windows operating systems starting with Windows 98 Second Edition. DirectMusic has since been deprecated, and is not available to 64-bit applications in Windows Vista. In Windows 7, native 64-bit support is available for the core DirectMusic API related to timestamped MIDI but not for the performance component.

DirectMusic provides a complete system for implementing dynamic soundtracks that take advantage of hardware acceleration, Downloadable Sounds (DLS), DirectX Media Objects (DMOs), advanced 3D positioning effects and several other features. DirectMusic provides composition and playback of dynamic musical soundtracks based on stored compositional material. Rather than a static playback, the music is generated on the fly, and is played with variations, and can respond to flexible program events. Using DirectMusic, it is possible to:

On Microsoft Windows Vista, DirectMusic uses only software synthesis. Also, the DirectMusic kernel mode synthesizer that supplies the DirectMusic components with a high-resolution timer has been removed.

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