How to convert decibel values into positive values? [closed]

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I'开发者_Python百科m getting the decibel values in negative. I just want to plot these values on a graph ranging from 0 to 100. So is there any way to convert the decibel values into positive values?

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It's quite common for 0 dB to correspond to full scale input (remember that a plain dB scale actually defines a ratio, not an absolute value, so the meaning of 0 dB is somewhat arbitrary). For e.g. 16 bit audio, values might typically range from 0 dB to -96 dB. To represent this on a scale of 0 - 100 you could just add 96 dB to bring this range up to 0..+96 dB.

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This is not a solution specific to decibels, but if you want your scale to be from 0-100, take your minimum value (lets call it minVal), and add -minVal to get 0. Then divide it by your maximum value, and multiply by 100.

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Just use fabs() C++ method

fabs function double fabs ( double x ); float fabs ( float x ); long double fabs ( long double x ); Compute absolute value

Returns the absolute value of x ( /x/ ).

In C++, abs is also declared in this header with the same behavior.

Parameters x Floating point value.

Return Value The absolute value of x.

Portability In C, only the double version of this function exists with this name.

fabs reference