FlatnessDB
extends BaseAlgorithm
in package
FlatnessDB
Inputs:
[vector_real] array - the input array
Outputs:
[real] flatnessDB - the flatness dB
Description:
This algorithm computes the flatness of an array, which is defined as the ratio between the geometric mean and the arithmetic mean converted to dB scale.
Specifically, it can be used to compute spectral flatness [1,2], which is a measure of how noise-like a sound is, as opposed to being tone-like. The meaning of tonal in this context is in the sense of the amount of peaks or resonant structure in a power spectrum, as opposed to flat spectrum of a white noise. A high spectral flatness (approaching 1.0 for white noise) indicates that the spectrum has a similar amount of power in all spectral bands — this would sound similar to white noise, and the graph of the spectrum would appear relatively flat and smooth. A low spectral flatness (approaching 0.0 for a pure tone) indicates that the spectral power is concentrated in a relatively small number of bands — this would typically sound like a mixture of sine waves, and the spectrum would appear "spiky"
The size of the input array must be greater than 0. If the input array is empty an exception will be thrown. This algorithm uses the Flatness algorithm and thus inherits its input requirements and exceptions.
References: [1] G. Peeters, "A large set of audio features for sound description (similarity and classification) in the CUIDADO project," CUIDADO I.S.T. Project Report, 2004
[2] Spectral flatness - Wikipedia, the free encyclopedia, http://en.wikipedia.org/wiki/Spectral_flatness
Category: Sfx Mode: standard
Table of Contents
Properties
- $algorithmName : string
- $category : string
- $essentia : EssentiaFFI
- $mode : string
- $parameters : array<string|int, mixed>
- $algorithmHandle : CData|null
- $configured : bool
Methods
- __construct() : mixed
- __destruct() : mixed
- compute() : array<string|int, mixed>
- getAlgorithmName() : string
- getCategory() : string
- getMode() : string
- getParameters() : array<string|int, mixed>
- setParameter() : self
- configure() : void
- isValidParameter() : bool
- validateInput() : void
- cleanupAlgorithm() : void
- configureAlgorithmParameters() : void
- estimateOutputSize() : int
- executeAlgorithm() : array<string|int, mixed>
- executeGenericAlgorithm() : array<string|int, mixed>
- executeSpecificAlgorithm() : array<string|int, mixed>
- getAlgorithmCreateFunction() : string
- getValidParameters() : array<string|int, mixed>
- initializeAlgorithm() : void
- prepareInput() : mixed
- processOutput() : array<string|int, mixed>
- processRhythmOutput() : array<string|int, mixed>
- processSpectralOutput() : array<string|int, mixed>
- processStatsOutput() : array<string|int, mixed>
- processTemporalOutput() : array<string|int, mixed>
- processTonalOutput() : array<string|int, mixed>
- setAlgorithmParameter() : void
- setArrayParameter() : void
- validateAlgorithmInput() : void
Properties
$algorithmName
protected
string
$algorithmName
= 'FlatnessDB'
$category
protected
string
$category
= 'Sfx'
$essentia
protected
EssentiaFFI
$essentia
$mode
protected
string
$mode
= 'standard'
$parameters
protected
array<string|int, mixed>
$parameters
= []
$algorithmHandle
private
CData|null
$algorithmHandle
= null
$configured
private
bool
$configured
= false
Methods
__construct()
public
__construct([array<string|int, mixed> $parameters = [] ]) : mixed
Parameters
- $parameters : array<string|int, mixed> = []
__destruct()
public
__destruct() : mixed
compute()
public
compute(mixed $input) : array<string|int, mixed>
Parameters
- $input : mixed
Return values
array<string|int, mixed>getAlgorithmName()
public
getAlgorithmName() : string
Return values
stringgetCategory()
public
getCategory() : string
Return values
stringgetMode()
public
getMode() : string
Return values
stringgetParameters()
public
getParameters() : array<string|int, mixed>
Return values
array<string|int, mixed>setParameter()
public
setParameter(string $key, mixed $value) : self
Parameters
- $key : string
- $value : mixed
Return values
selfconfigure()
protected
configure(array<string|int, mixed> $parameters) : void
Parameters
- $parameters : array<string|int, mixed>
isValidParameter()
protected
isValidParameter(string $parameter) : bool
Parameters
- $parameter : string
Return values
boolvalidateInput()
protected
validateInput(mixed $input, string $expectedType) : void
Parameters
- $input : mixed
- $expectedType : string
cleanupAlgorithm()
private
cleanupAlgorithm() : void
configureAlgorithmParameters()
private
configureAlgorithmParameters() : void
estimateOutputSize()
private
estimateOutputSize(mixed $input) : int
Parameters
- $input : mixed
Return values
intexecuteAlgorithm()
private
executeAlgorithm(mixed $input) : array<string|int, mixed>
Parameters
- $input : mixed
Return values
array<string|int, mixed>executeGenericAlgorithm()
private
executeGenericAlgorithm(FFI $ffi, mixed $input) : array<string|int, mixed>
Parameters
- $ffi : FFI
- $input : mixed
Return values
array<string|int, mixed>executeSpecificAlgorithm()
private
executeSpecificAlgorithm(FFI $ffi, mixed $input) : array<string|int, mixed>
Parameters
- $ffi : FFI
- $input : mixed
Return values
array<string|int, mixed>getAlgorithmCreateFunction()
private
getAlgorithmCreateFunction() : string
Return values
stringgetValidParameters()
private
getValidParameters() : array<string|int, mixed>
Return values
array<string|int, mixed>initializeAlgorithm()
private
initializeAlgorithm() : void
prepareInput()
private
prepareInput(mixed $input) : mixed
Parameters
- $input : mixed
processOutput()
private
processOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>processRhythmOutput()
private
processRhythmOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>processSpectralOutput()
private
processSpectralOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>processStatsOutput()
private
processStatsOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>processTemporalOutput()
private
processTemporalOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>processTonalOutput()
private
processTonalOutput(array<string|int, mixed> $result) : array<string|int, mixed>
Parameters
- $result : array<string|int, mixed>
Return values
array<string|int, mixed>setAlgorithmParameter()
private
setAlgorithmParameter(FFI $ffi, string $key, mixed $value) : void
Parameters
- $ffi : FFI
- $key : string
- $value : mixed
setArrayParameter()
private
setArrayParameter(FFI $ffi, string $key, array<string|int, mixed> $value) : void
Parameters
- $ffi : FFI
- $key : string
- $value : array<string|int, mixed>
validateAlgorithmInput()
private
validateAlgorithmInput(mixed $input) : void
Parameters
- $input : mixed