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DirectSound also allows several applications to conveniently share access to the sound card at the same time. Its ability to play sound in 3D added a new dimension to games. It also provides the ability for games to modify a musical script in response to game events in real time, ie: the beat of the music could quicken as the action heats up.

After many years of development, today DirectSound is a very mature API , and supplies many other useful capabilities, such as the ability to play multichannel sound and sounds at high resolution. While DirectSound was designed to be used by games, a number of professional audio applications now take advantage of its many diverse capabilities.


DIRECTSOUND3D


DirectSound3D (DS3D) is an addition to Microsoft's DirectX system which is intended to standardize 3D Audio under Microsoft Windows , introduced with DirectX 3 in 1996.

DirectSound3D allows software developers to write to a single standardized audio API instead of writing code for each audio card manufacturer.

In DirectX 5, DirectSound3D has the capability of having sound cards that use third party 3D audio algorithms accelerate DirectSound3D properly, through Microsoft-approved methods. This eliminate the need for separate 3D audio libraries.

Starting wih DirectX 8 onwards, DirectSound and DirectSound3D (DS3D) are together referred to as DirectX Audio.


WINDOWS VISTA

Windows Vista features a completely re-written audio Stack . Because of the architectural changes in the redesigned audio stack, a direct path from DirectSound to the audio drivers does not exist. DirectSound and other APIs such as MME are emulated as WASAPI Session instances. DirectSound runs in emulation mode on the Microsoft software mixer. The emulator does not have hardware abstraction, so there is no hardware DirectSound acceleration, meaning hardware and software relying on DirectSound acceleration will have degraded performance. However, the performance hit might not be noticeable if the CPU or CPUs are powerful enough. In the case of hardware 3D Audio Effect s played using DirectSound3D, they will not be playable.

Third-party APIs such as ASIO and OpenAL are not affected by these architectural changes in Windows Vista. A solution for applications that wish to take advantage of hardware accelerated high-quality 3D positional audio is to use OpenAL. However, this only works if the manufacturer provides an OpenAL driver for their hardware.

As of 2007, a solution to re-enable hardware acceleration of DirectSound3D and Audio Effects, such as EAX, called 'Creative ALchemy' was launched. Creative ALchemy intercepts calls to DirectSound3D and translates them into OpenAL calls to be processed by supported hardware such as Sound Blaster X-Fi and Sound Blaster Audigy .


XAUDIO


Because of , Windows Vista and the Xbox 360. It will provide high-level audio authoring/playback via XACT and 3D functions via the X3DAudio library. The XACT engine is a high-level audio Programming Library that is written to use Xaudio on the Xbox, DirectSound on Windows XP , and the New Audio Stack on Windows Vista . X3DAudio is a spatialization helper library available on both platforms, Windows and the Xbox.

Xaudio 2 will have special emphasis on Signal Processing for high-level audio APIs such as XACT . Some of the slated features are:

  • Separation of sound data from “voice”

  • Submixing

  • Multi-rate processing

  • Per-voice filtering

  • Programmable voices

  • Effects processing, Sample Rate Conversion (SRC)

  • Software DSP

  • Enhanced Surround Sound (multichannel) and explicit multichannel Panning /mapping

  • Native compressed data support

  • --- XMA on Xbox 360

  • --- ADPCM on Windows

  • --- Extensible

  • 3D audio handled as a separate replaceable library: XAudio 2 takes multichannel speaker volumes and X3DAudio library transforms source/listener coordinates into speaker volumes and other synthesis parameters



WINDOWS CE

Although DirectSound support was available in Windows CE versions up to 4.2, it was removed starting 5.0 Windows CE 5.0 removed functionality . Windows CE 6.0 also does not support DirectSound, instead favoring that applications be rewritten to use the Waveform Audio API.


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