Math Macros

mathematical operations and values needed for functions within this library More...

Defines
#define	PI   3.141592653589793238462643
#define	TWO_PI   6.28318530717958647692
#define	INV_TWO_PI   (1 / TWO_PI)
#define	PI_2   1.57079632679489661923
#define	LOG2   0.69314718055994529
#define	LOG10   2.3025850929940459
#define	EXP   2.7182818284590451
#define	MAX(a, b)   ((a) > (b) ? (a) : (b))
	returns the maximum of a and b
#define	MIN(a, b)   ((a) < (b) ? (a) : (b))
	returns the minimum of a and b
Functions
sfloat	sms_magToDB (sfloat x)
	convert from magnitude to decibel
sfloat	sms_dBToMag (sfloat x)
	convert from decibel to magnitude
void	sms_arrayMagToDB (int sizeArray, sfloat *pArray)
	convert an array from magnitude to decibel
void	sms_arrayDBToMag (int sizeArray, sfloat *pArray)
	convert and array from decibel (0-100) to magnitude (0-1)
void	sms_setMagThresh (sfloat x)
	set the linear magnitude threshold
sfloat	sms_rms (int sizeArray, sfloat *pArray)
	Root Mean Squared of an array.
sfloat	sms_sine (sfloat fTheta)
	table-lookup sine method
sfloat	sms_sinc (sfloat fTheta)
	global sinc table-lookup method
sfloat	sms_random (void)
	random number genorator
int	sms_power2 (int n)
	make sure a number is a power of 2
sfloat	sms_scalarTempered (float x)
void	sms_arrayScalarTempered (int sizeArray, sfloat *pArray)
	scale an array of linear frequencies to the well-tempered scale

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Detailed Description

mathematical operations and values needed for functions within this library

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Define Documentation

#define EXP   2.7182818284590451

Eurler's number

Referenced by sms_dCepstrumEnvelope().

#define INV_TWO_PI   (1 / TWO_PI)

1 / ( pi * 2)

Referenced by SineSynthIFFT(), sms_deterministic(), and sms_sine().

#define LOG10   2.3025850929940459

natural logarithm of 10

#define LOG2   0.69314718055994529

natural logarithm of 2

Referenced by InitializeHybrid().

#define MAX	(	a,
		b		)	((a) > (b) ? (a) : (b))

returns the maximum of a and b

Referenced by MultiplySpectra(), sms_analyze(), sms_detectPeaks(), sms_fillSoundBuffer(), sms_initAnalParams(), and sms_spectralApprox().

#define MIN	(	a,
		b		)	((a) < (b) ? (a) : (b))

returns the minimum of a and b

Referenced by FillGap(), sms_analyze(), sms_copyFrame(), sms_detectPeaks(), and sms_spectralApprox().

#define PI   3.141592653589793238462643

pi

Referenced by GetPhaseVal(), Hanning(), and sms_dCepstrum().

#define PI_2   1.57079632679489661923

pi / 2

Referenced by SinePhaSynth(), SineSynthIFFT(), sms_dCepstrum(), and sms_deterministic().

#define TWO_PI   6.28318530717958647692

pi * 2

Referenced by BlackmanHarris62(), BlackmanHarris70(), BlackmanHarris74(), BlackmanHarris92(), FillGap(), GetPhaseVal(), Hamming(), IFFTwindow(), SinePhaSynth(), SineSynth(), SineSynthIFFT(), sms_deterministic(), sms_prepSinc(), sms_prepSine(), sms_sine(), sms_sineSynthFrame(), sms_stochastic(), and StocSynthApprox().

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Function Documentation

void sms_arrayDBToMag	(	int	sizeArray,
		sfloat *	pArray
	)

convert and array from decibel (0-100) to magnitude (0-1)

depends on the magnitude threshold

See also:

sms_setMagThresh

Parameters:

	sizeArray	size of array
	pArray	pointer to array

References sms_dBToMag().

Referenced by sms_analyze().

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void sms_arrayMagToDB	(	int	sizeArray,
		sfloat *	pArray
	)

convert an array from magnitude to decibel

Depends on a linear threshold that indicates the bottom end of the dB scale (magnutdes at this value will convert to zero).

See also:

sms_setMagThresh

Parameters:

	sizeArray	size of array
	pArray	pointer to array

References sms_magToDB().

Referenced by sms_analyzeFrame().

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void sms_arrayScalarTempered	(	int	sizeArray,
		sfloat *	pArray
	)

scale an array of linear frequencies to the well-tempered scale

Parameters:

	sizeArray	size of the array
	pArray	pointer to array of frequencies

References sms_scalarTempered().

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sfloat sms_dBToMag

(

sfloat

x

)

convert from decibel to magnitude

Parameters:

x

decibel (0-100)

Returns:

magnitude (0-1)

References mag_thresh.

Referenced by SinePhaSynth(), SineSynth(), sms_arrayDBToMag(), and sms_scaleDet().

sfloat sms_magToDB

(

sfloat

x

)

convert from magnitude to decibel

Parameters:

x

magnitude (0:1)

Returns:

decibel (0: -100)

References inv_mag_thresh, mag_thresh, and TWENTY_OVER_LOG10.

Referenced by sms_arrayMagToDB(), and sms_scaleDet().

int sms_power2

(

int

n

)

make sure a number is a power of 2

Returns:

a power of two integer >= input value

Referenced by sms_analyze(), sms_analyzeFrame(), sms_dCepstrumEnvelope(), sms_initAnalysis(), sms_initSynth(), sms_invSpectrum(), sms_spectrum(), sms_spectrumMag(), and sms_stocAnalysis().

sfloat sms_random

(

void

)

random number genorator

Returns:

random number between -1 and 1

References genrand_real1(), INV_HALF_MAX, and sfloat.

Referenced by SineSynth(), SineSynthIFFT(), sms_deterministic(), sms_stochastic(), and StocSynthApprox().

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sfloat sms_rms	(	int	sizeArray,
		sfloat *	pArray
	)

Root Mean Squared of an array.

Returns:

RMS energy

References sfloat.

sfloat sms_scalarTempered

(

float

x

)

Todo:

remove this define now that there is sms_scalerTempered

void sms_setMagThresh

(

sfloat

x

)

set the linear magnitude threshold

magnitudes below this will go to zero when converted to db. it is limited to 0.00001 (-100db)

Parameters:

x

threshold value

References inv_mag_thresh, and mag_thresh.

sfloat sms_sinc

(

sfloat

fTheta

)

global sinc table-lookup method

fTheta has to be from 0 to 8

Parameters:

fTheta

angle in radians

Returns:

approximately sinc(fTheta)

References fSincScale, and sms_tab_sinc.

Referenced by SineSynthIFFT(), and sms_deterministic().

sfloat sms_sine

(

sfloat

fTheta

)

table-lookup sine method

Parameters:

fTheta

angle in radians

Returns:

approximately sin(fTheta)

References fSineIncr, INV_TWO_PI, sms_tab_sine, and TWO_PI.

Referenced by SineSynth(), SineSynthIFFT(), sms_dCepstrum(), and sms_deterministic().