Custom Audio Effects in Windows Vista Custom Audio Effects in Windows Vista

Introduction

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  Speaker fill
  
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  Headphone virtualization
  
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  Room correction
  
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  Output encoding for external decoders
  
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  Automatic gain control
  
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  Microphone array filters
  

When users install an audio device driver by using the standard INF file, they automatically have access to the system's sAPOs. Independent hardware vendors (IHVs) and original equipment manufacturers (OEMs) can provide additional custom system effects while still using the Microsoft class drivers. They do so by packaging their DSP algorithms as sAPOs and modifying the standard INF file to insert their sAPOs into the audio engine’s signal processing graph.

This white paper provides guidelines for vendors who want to create and install custom sAPOs.