AecQualityMetrics_Struct structure (wmcodecdsp.h)

Contains quality metrics for acoustic echo cancellation (AEC). This structure is used with the MFPKEY_WMAAECMA_RETRIEVE_TS_STATS property.

Syntax

typedef struct tagAecQualityMetrics_Struct {
  LONGLONG i64Timestamp;
  BYTE     ConvergenceFlag;
  BYTE     MicClippedFlag;
  BYTE     MicSilenceFlag;
  BYTE     PstvFeadbackFlag;
  BYTE     SpkClippedFlag;
  BYTE     SpkMuteFlag;
  BYTE     GlitchFlag;
  BYTE     DoubleTalkFlag;
  ULONG    uGlitchCount;
  ULONG    uMicClipCount;
  float    fDuration;
  float    fTSVariance;
  float    fTSDriftRate;
  float    fVoiceLevel;
  float    fNoiseLevel;
  float    fERLE;
  float    fAvgERLE;
  DWORD    dwReserved;
} AecQualityMetrics_Struct;

Members

i64Timestamp

Time stamp that indicates when the quality metrics were collected.

ConvergenceFlag

AEC convergence flag.

MicClippedFlag

If TRUE, the input signal from the audio capture device was clipped.

MicSilenceFlag

If TRUE, the input signal from the audio capture device was silent or too quiet.

PstvFeadbackFlag

If TRUE, positive feedback is causing a chirping sound.

SpkClippedFlag

If TRUE, the input signal from the audio rendering device was clipped.

SpkMuteFlag

If TRUE, the input signal from the audio rendering device was silent or too quiet.

GlitchFlag

A glitch occurred in the input data.

DoubleTalkFlag

Double talk flag.

uGlitchCount

Number of glitches.

uMicClipCount

Number of times the audio capture signal was clipped.

fDuration

Running duration of the AEC process.

fTSVariance

Long-term average variance in the time stamps.

fTSDriftRate

Long-term average drift rate in the time stamps.

fVoiceLevel

Near-end voice level after AEC processing.

fNoiseLevel

Noise level of the audio capture signal.

fERLE

Echo return loss enhancement (ERLE).

fAvgERLE

Average ERLE over the entire duration of AEC processing.

dwReserved

Reserved

Requirements

Requirement	Value
Minimum supported client	Windows XP [desktop apps only]
Minimum supported server	Windows Server 2003 [desktop apps only]
Header	wmcodecdsp.h

See also

Media Foundation Structures

Voice Capture DSP