Copyright © 2001-2008 MultiMedia Soft 
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PreAmplifierGetSpeakerValue method 
 
Remarks 
 
Gets the current preamplifier's amplification value related to a specific speaker (only for multi-channel songs like 5.1 or 7.1). The current value can be modified through the PreAmplifierSetSpeakerValue method. 
Pre-amplification is applied only if enabled through a previous call to the PreAmplifierEnable method. 
 
 
Syntax 
 
[Visual Basic] 
control.PreAmplifierGetSpeakerValue
nPlayer as Integer
nSpeaker as enumSpeakers 
fValue as Single
nScaleType as enumVolumeScales 
 
[C++] 
short control.PreAmplifierGetSpeakerValue
short nPlayer, 
short nSpeaker, 
float *fValue, 
short nScaleType 
);
 
 
Parameter
Description
 
 
nPlayer
Number representing the zero-based index of the involved player
nSpeaker
The output speaker assigned to the given player. 
Supported values are the following: 
Mnemonic value
Numeric value
Meaning
SPEAKER_FRONT
0
Front speakers (Stereo)
SPEAKER_REAR
1
Rear speakers (Stereo)
SPEAKER_CENTER_LFE
2
Center speakers (Stereo)
SPEAKER_REAR_CENTER
3
Rear center speakers (Stereo)
SPEAKER_FRONT_LEFT
4
Front-left speaker (Mono)
SPEAKER_FRONT_RIGHT
5
Front-right speaker (Mono)
SPEAKER_REAR_LEFT
6
Rear-left speaker (Mono)
SPEAKER_REAR_RIGHT
7
Rear-right speaker (Mono)
SPEAKER_CENTER
8
Center speaker (Mono)
SPEAKER_LFE
9
LFE or Subwoofer speaker (Mono)
SPEAKER_REAR_CENTER_LEFT
10
Rear Center Left speaker (Mono)
SPEAKER_REAR_CENTER_RIGHT
11
Rear Center Right speaker (Mono)
 
Below you can see the positioning of the Stereo speakers on a wide 7.1 configuration (the reported blue numbers corresponds to the Numeric value of the parameter) 
 
and below you can see the positioning of the Mono speakers on the same wide 7.1 configuration 
 
fValue
Reference that, on return from the method call, will contain the amplification value expressed in the unit specified by the nScaleType parameter.
nScaleType
The amplification scaling type. 
Supported values are the following: 
Mnemonic constant
Value
Meaning
SCALE_LINEAR
0
Returned amplification, expressed in percentage, is based upon a linear scale: 
- value 0.0 mutes the playing sound 
- values higher than 0.0 and smaller than 100.0 attenuate the playing sound 
- value 100.0 keeps sound level unchanged 
- values higher than 100.0 amplify the playing sound
SCALE_LOG
1
Returned amplification, expressed in dB, is based upon a logarithmic scale: 
- value -100.0 mutes the playing sound 
- values higher than -100.0 and smaller than 0.0 attenuate the playing sound 
- value 0.0 keeps sound level unchanged 
- values higher than 0.0 amplify the playing sound 
 
The actual applied formula for converting a linear volume into a logarithmic volume is the following: 
VolumeInDB = 20 * log10 (VolumeLinear/100) 
The C syntax for converting a logarithmic volume into a linear volume is the following: 
float e = 2.7182818281f; 
float exp = (float)((fVolumeInDB + (20 * log(100))) / 20); 
fVolumeLinear = (float) pow (e, exp);
 
 
Return value 
 
Value
Meaning
 
 
Negative value
An error occurred (see the LastError property for further error details)
enumErrorCodes.ERR_NOERROR (0)
The call was successful.
 
 
 
 
 
 
 
 
 
Copyright © 2001-2008 MultiMedia Soft 
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