Enumerations
enum	mel_base { base_e, base_10 }

Functions
template<typename T >
constexpr T	bark2hertz (T z) noexcept
	Converts a critical band rate in Bark scale to Hertz. More...

template<typename InputIt , typename OutputIt >
constexpr void	complex2real (InputIt first, InputIt last, OutputIt d_first1, OutputIt d_first2)
	Converts a range of complex numbers in two ranges storing the real and imaginary parts. More...

template<typename T >
constexpr T	db2mag (T db) noexcept
	Convert decibels to magnitude. More...

template<typename T >
constexpr T	db2pow (T db) noexcept
	Convert decibels to power. More...

template<typename T >
constexpr T	deg2rad (T degree) noexcept
	Convert angle from degrees to radians. More...

template<typename T >
constexpr T	bark2band (T z) noexcept
	Converts a frequency in Hertz into its equivalent Bark scale value. More...

template<mel_base scale, typename T >
constexpr T	hertz2mel (T f) noexcept
	Converts a frequency in Hertz into mels. More...

template<typename T >
constexpr T	mag2db (T magnitude) noexcept
	Convert magnitude to decibels (dB) More...

template<mel_base scale, typename T >
constexpr T	mel2hertz (T mel) noexcept
	Converts a frequency in mels to Hertz. More...

template<typename ForwardIt >
constexpr meta::value_type_t< ForwardIt >	peak2peak (ForwardIt first, ForwardIt last)
	Maximum-to-minimum difference in the range [first, last) More...

template<typename ForwardIt >
constexpr meta::value_type_t< ForwardIt >	peak2rms (ForwardIt first, ForwardIt last)
	Maximum Peak-magnitude-to-RMS ratio in the range [first, last) More...

template<typename T >
constexpr T	pow2db (T power) noexcept
	Convert power to decibels. More...

template<typename T >
constexpr T	rad2deg (T radians) noexcept
	Convert angle from radians to degrees. More...

template<typename T >
constexpr std::complex< T >	real2complex (T real, T imag=static_cast< T >(0)) noexcept
	Converts a real scalar to an equivalent complex number. More...

template<typename InputIt , typename OutputIt >
constexpr void	real2complex (InputIt first, InputIt last, OutputIt d_first)
	Converts a range of scalar numbers in to an equivalent complex number and stores the result in another range. More...

template<typename InputIt , typename OutputIt >
constexpr void	real2complex (InputIt first1, InputIt last1, InputIt first2, OutputIt d_first)
	Converts a range of scalar numbers in to an equivalent complex number and stores the result in another range. More...

Enumeration Type Documentation

◆ mel_base

enum edsp::converter::mel_base

Enumerator
base_e	e base
base_10	10 base

Function Documentation

◆ bark2band()

template<typename T >

constexpr T edsp::converter::bark2band ( T z )

noexcept

Converts a frequency in Hertz into its equivalent Bark scale value.

The conversion of a frequency f (Hz) into Bark is implemented as follows:

\[ { \alpha =[(26.81f)/(1960+f)]-0.53\, f] An then: - If \f$ \alpha < 2 \f$ then \f$ f_b = 0.15 * (2 - \alpha) \f$. - If \f$ \alpha > 20.1 \f$ then \f$ f_b = 0.22 * (\alpha - 20.1) \f$. @param f Frequency in Hz @returns Frequency in Bark scale. @see bark2band, hertz2band */ template <typename T> constexpr T hertz2bark(T f) noexcept { const auto b = (26.81 * f) / (1960 + f) - 0.53; if (b < 2) { b += 0.15 * (2 - b); } if (b > 20.1) { b += 0.22 * (b - 20.1); } return b; } /** @brief Converts a critical band rate in Bark into a critical bandwidth in Hz. The conversion of a critical band rate z into a critical bandwidth in Hz is implemented as follows: \f[ f = 52548/ (z^{2}-52.56z+690.39)\, with z in bark. \]

or

\[ {\displaystyle f=600\sinh(z/6)} {\displaystyle f=600\sinh(z/6)} \]

Parameters

z	The critical band rate, in Bark

Returns: The critical bandwidth in Hz.

◆ bark2hertz()

template<typename T >

constexpr T edsp::converter::bark2hertz ( T z )

noexcept

Converts a critical band rate in Bark scale to Hertz.

The conversion of a critical band rate z into Hertz is as follows:

\[ f = 52548/ (z^{2}-52.56z+690.39)\, with z in bark. \]

or

\[ {\displaystyle f=600\sinh(z/6)} {\displaystyle f=600\sinh(z/6)} \]

Parameters

z	The critical band rate, in Bark

Returns: Frequency in Hz.

See also: hertz2bark

◆ complex2real()

template<typename InputIt , typename OutputIt >

constexpr void edsp::converter::complex2real	(	InputIt	first,
		InputIt	last,
		OutputIt	d_first1,
		OutputIt	d_first2
	)

Converts a range of complex numbers in two ranges storing the real and imaginary parts.

Parameters

first	Input iterator defining the beginning of the range.
last	Input iterator defining the ending of the range.
d_first1	Output iterator defining the beginning of the real part.
d_first2	Output iterator defining the beginning of the imaginary part.

◆ db2mag()

template<typename T >

constexpr T edsp::converter::db2mag ( T db )

noexcept

Convert decibels to magnitude.

The output is computed as follows:

\[ y = 10^{\frac{x}{20}} \]

Parameters

db	Scalar number in decibels.

Returns: Magnitude measurement, returned as a scalar.

◆ db2pow()

template<typename T >

constexpr T edsp::converter::db2pow ( T db )

noexcept

Convert decibels to power.

The output is computed as follows:

\[ y = 10^{\frac{x}{10}} \]

Parameters

db	Scalar number in decibels.

Returns: Power measurements.

◆ deg2rad()

template<typename T >

constexpr T edsp::converter::deg2rad ( T degree )

noexcept

Convert angle from degrees to radians.

The output is computed as follows:

\[ y = \frac{x\pi}{180} \]

Parameters

degree Angle in degrees

Returns: Angle in radians

◆ hertz2mel()

template<mel_base scale, typename T >

constexpr T edsp::converter::hertz2mel ( T f )

noexcept

Converts a frequency in Hertz into mels.

The popular formula from O'Shaugnessy's book can be expressed with different logarithmic bases:

\[ {\displaystyle m=2595\log _{10}\left(1+{\frac {f}{700}}\right)=1127\ln \left(1+{\frac {f}{700}}\right)} \]

Parameters

f	Frequency in Hertz.

Returns: Frequency in mels.

See also: mel2hertz, mel_base

◆ mag2db()

template<typename T >

constexpr T edsp::converter::mag2db ( T magnitude )

noexcept

Convert magnitude to decibels (dB)

The output is computed as follows:

\[ y = 20 \log10{ \left( x \right) } \]

Parameters

magnitude Scalar number in magnitude scale.

Returns: Scalar number in decibels.

◆ mel2hertz()

template<mel_base scale, typename T >

constexpr T edsp::converter::mel2hertz ( T mel )

noexcept

Converts a frequency in mels to Hertz.

Depending of the base, the corresponding inverse expressions are:

\[ {\displaystyle f=700\left(10^{\frac {m}{2595}}-1\right)=700\left(e^{\frac {m}{1127}}-1\right)} \]

Parameters

mel	Frequency in mels.

Returns: Frequency in Hz.

See also: hertz2mel

◆ peak2peak()

template<typename ForwardIt >

constexpr meta::value_type_t<ForwardIt> edsp::converter::peak2peak	(	ForwardIt	first,
		ForwardIt	last
	)

Maximum-to-minimum difference in the range [first, last)

Parameters

first	Forward iterator defining the begin of the range to examine.
last	Forward iterator defining the end of the range to examine.

Returns: Maximum-to-minimum difference.

◆ peak2rms()

template<typename ForwardIt >

constexpr meta::value_type_t<ForwardIt> edsp::converter::peak2rms	(	ForwardIt	first,
		ForwardIt	last
	)

Maximum Peak-magnitude-to-RMS ratio in the range [first, last)

Returns the ratio of the largest absolute value in the range [first, last) to the root-mean-square (RMS) value of the range. The Peak-magnitude-to-RMS Level is:

\[ y =\frac{\left| x \right|_{\infty}}{\sqrt{\frac{1}{N}\sum_{n=0}^{N-1}\left|x\left(i\right)\right|^2}} \]

Parameters

first	Forward iterator defining the begin of the range to examine.
last	Forward iterator defining the end of the range to examine.

Returns: Peak-magnitude-to-RMS ratio.

◆ pow2db()

template<typename T >

constexpr T edsp::converter::pow2db ( T power )

noexcept

Convert power to decibels.

The output is computed as follows:

\[ y = 10 \log10{\left( x \right)} \]

Parameters

power Scalar number representing the power of a sample.

Returns: Power measurement in decibel (dB).

◆ rad2deg()

template<typename T >

constexpr T edsp::converter::rad2deg ( T radians )

noexcept

Convert angle from radians to degrees.

The output is computed as follows:

\[ y = x \frac{180}{\pi} \]

Parameters

radians Angle in radians.

Returns: Angle in degrees.

◆ real2complex() [1/3]

template<typename T >

constexpr std::complex<T> edsp::converter::real2complex	(	T	real,
		T	imag = `static_cast<T>(0)`
	)

noexcept

Converts a real scalar to an equivalent complex number.

Parameters

real	Scalar number representing the real part of the complex number.
imag	Scalar number representing the imaginary part of the complex number.

Returns: Returns the complex-valued.

◆ real2complex() [2/3]

template<typename InputIt , typename OutputIt >

constexpr void edsp::converter::real2complex	(	InputIt	first,
		InputIt	last,
		OutputIt	d_first
	)

Converts a range of scalar numbers in to an equivalent complex number and stores the result in another range.

Note: Use this function when the output range does not have an imaginary part.

Parameters

first	Input iterator defining the beginning of the range representing the real part.
last	Input iterator defining the ending of the range representing the real part.
d_first	Output iterator defining the beginning of the destination range.

◆ real2complex() [3/3]

template<typename InputIt , typename OutputIt >

constexpr void edsp::converter::real2complex	(	InputIt	first1,
		InputIt	last1,
		InputIt	first2,
		OutputIt	d_first
	)

Converts a range of scalar numbers in to an equivalent complex number and stores the result in another range.

Parameters

first1	Input iterator defining the beginning of the range representing the real part.
last1	Input iterator defining the ending of the range representing the real part.
first2	Input iterator defining the beginning of the range representing the imaginary part.
d_first	Output iterator defining the beginning of the destination range.

Enumerations

Functions

Enumeration Type Documentation

◆ mel_base

Function Documentation

◆ bark2band()

◆ bark2hertz()

◆ complex2real()

◆ db2mag()

◆ db2pow()

◆ deg2rad()

◆ hertz2mel()

◆ mag2db()

◆ mel2hertz()

◆ peak2peak()

◆ peak2rms()

◆ pow2db()

◆ rad2deg()

◆ real2complex() [1/3]

◆ real2complex() [2/3]

◆ real2complex() [3/3]