`delta' extraction functions

Functions
int	xtract_flux (const double *data, const int N, const void *argv, double *result)
	Extract flux. More...
int	xtract_lnorm (const double *data, const int N, const void *argv, double *result)
	Extract the L-norm of a vector. More...
int	xtract_attack_time (const double *data, const int N, const void *argv, double *result)
	Extract attack Time.
int	xtract_decay_time (const double *data, const int N, const void *argv, double *result)
int	xtract_difference_vector (const double *data, const int N, const void *argv, double *result)
	Extract the difference between two vectors. More...

Detailed Description

Functions that extract a scalar or vector value from 2 or more input vectors

Function Documentation

int xtract_decay_time	(	const double *	data,
		const int	N,
		const void *	argv,
		double *	result
	)

Extract temporal decrease

int xtract_difference_vector	(	const double *	data,
		const int	N,
		const void *	argv,
		double *	result
	)

Extract the difference between two vectors.

Parameters

*data	a pointer to an array representing two distinct vectors, e.g. two successive magnitude spectra.
N	the size of the array pointed to by *data
*argv	a pointer to NULL
*result	a pointer to an array of size N / 2 representing the difference between the two input vectors.

int xtract_flux	(	const double *	data,
		const int	N,
		const void *	argv,
		double *	result
	)

Extract flux.

Note

FIX: don't be lazy – take the lnorm of the difference vector! An alias for xtract_lnorm()

int xtract_lnorm	(	const double *	data,
		const int	N,
		const void *	argv,
		double *	result
	)

Extract the L-norm of a vector.

Parameters

*data	a pointer to the first element in an array of doubles representing the difference between two subsequent frames of output from a vector-based feature e.g. the *result from xtract_difference_vector()
N	the length of the array pointed to by *data
*argv	a pointer to an array of doubles, the first representing the "norm order". The second argument represents the filter type determining what values we consider from the difference vector as given in the enumeration xtract_lnorm_filter_types_ (libxtract.h), the third sets whether we want the result to be normalised in the range 0-1 (0 = no normalise, 1 = normalise)
*result	a pointer to a double representing the flux