DRC Virtual Surround Overview

Introduction

DRC virtual surround (VS) expands DRC audio output virtually.

To enable DRC VS, the following steps are required:

  1. The end-user selects "SURROUND" for DRC audio output in the System Config Tool.
  2. In AXSetDRCVSMode, pass something other than AX_DRC_VS_OFF.
  3. In AXSetVoiceDeviceMix, enable the DRC rear channel, or in AXRegisterDeviceFinalMixCallback, mix voices with the DRC rear channel.

Processing Flow

After FinalMixCallback (set by AXRegisterDeviceFinalMixCallback), DRC VS is processed according to the following flow.

The user can modify red-squared areas.
Some parameters (with "HP/SP" indications) can take different values between speaker output and headphone output.

The flow for each mode set by AXSetDRCVSMode is shown below:

The symbols in the diagrams indicate as follows:

SymbolMeaning
Fl Front L channel; equivalent to AX_CH_LEFT in AXPB_CH_ID
Fr Front R channel; equivalent to AX_CH_RIGHT in AXPB_CH_ID
Sl Rear L channel; equivalent to AX_CH_SUR_LEFT in AXPB_CH_ID
Sr Rear R channel; equivalent to AX_CH_SUR_RIGHT in AXPB_CH_ID
LoutL channel for DRC audio output
RoutR channel for DRC audio output

AX_DRC_VS_OFF

AX_DRC_VS_ON_NORMAL

AX_DRC_VS_ON_FRONT_BYPASS

See Also

AXSetDRCVSMode
AXGetDRCVSMode
AXSetDRCVSLC
AXSetDRCVSSpeakerPosition
AXSetDRCVSSurroundDepth
AXSetDRCVSDownmixBalance
AXSetDRCVSSurroundLevelGain
AXSetDRCVSOutputGain

Revision History

2013/05/08 Automated cleanup pass.
2012/09/25 Typo
2012/07/12 Modified to reflect the front bypass support implemented in SDK 2.06.02
2012/06/27 Removed the DRC-MP-related note
2011/06/06 Initial Version for SDK 2.06


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