Mnemonic constant

Value

Meaning

SCALE_LINEAR

0

Volume is based upon a linear scale and can be in the range from 0.0 (silence) to 100.0 (max volume)

SCALE_LOG

1

Volume, expressed in dB, is based upon a logarithmic scale and can be in the range from -100  (silence) to 0 (max volume)

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:

VolumeLinear = 100 * pow (10, VolumeInDB/20);