DSFXDistortion Structure

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The DSFXDistortion structure contains parameters for a distortion effect.

Syntax

typedef struct DSFXDistortion {
    DWORD fGain;
    DWORD fEdge;
    DWORD fPostEQCenterFrequency;
    DWORD fPostEQBandwidth;
    DWORD fPreLowpassCutoff;
} DSFXDistortion;

Members

  • fGain
    Amount of signal change after distortion, in the range from DSFXDISTORTION_GAIN_MIN through DSFXDISTORTION_GAIN_MAX. The default value is -18 dB.
  • fEdge
    Percentage of distortion intensity, in the range in the range from DSFXDISTORTION_EDGE_MIN through DSFXDISTORTION_EDGE_MAX. The default value is 15 percent.
  • fPostEQCenterFrequency
    Center frequency of harmonic content addition, in the range from DSFXDISTORTION_POSTEQCENTERFREQUENCY_MIN through DSFXDISTORTION_POSTEQCENTERFREQUENCY_MAX. The default value is 2400 Hz.
  • fPostEQBandwidth
    Width of frequency band that determines range of harmonic content addition, in the range from DSFXDISTORTION_POSTEQBANDWIDTH_MIN through DSFXDISTORTION_POSTEQBANDWIDTH_MAX. The default value is 2400 Hz.
  • fPreLowpassCutoff
    Filter cutoff for high-frequency harmonics attenuation, in the range from DSFXDISTORTION_PRELOWPASSCUTOFF_MIN through DSFXDISTORTION_PRELOWPASSCUTOFF_MAX. The default value is 8000 Hz.

Remarks

The values in fPostEQBandwidth, fPostEQCenterFrequency, and fPreLowpassCutoff cannot exceed one-third of the frequency of the buffer. If an attempt is made to set a value greater than this, but within the range of accepted values, the parameter is set to the nearest supported value and S_FALSE is returned by IDirectSoundFXDistortion8::SetAllParameters.

Requirements

Header: Declared in DSound.h.

See Also

Distortion
IDirectSoundFXDistortion8