SpectralContrast
extends BaseAlgorithm
in package
SpectralContrast
Inputs:
[vector_real] spectrum - the audio spectrum
Outputs:
[vector_real] spectralContrast - the spectral contrast coefficients [vector_real] spectralValley - the magnitudes of the valleys
Parameters:
frameSize: integer ∈ [2,inf) (default = 2048) the size of the fft frames
highFrequencyBound: real ∈ (0,inf) (default = 11000) the upper bound of the highest band
lowFrequencyBound: real ∈ (0,inf) (default = 20) the lower bound of the lowest band
neighbourRatio: real ∈ (0,1] (default = 0.40000000596) the ratio of the bins in the sub band used to calculate the peak and valley
numberBands: integer ∈ (0,inf) (default = 6) the number of bands in the filter
sampleRate: real ∈ (0,inf) (default = 22050) the sampling rate of the audio signal
staticDistribution: real ∈ [0,1] (default = 0.15000000596) the ratio of the bins to distribute equally
Description:
This algorithm computes the Spectral Contrast feature of a spectrum. It is based on the Octave Based Spectral Contrast feature as described in [1]. The version implemented here is a modified version to improve discriminative power and robustness. The modifications are described in [2].
References: [1] D.-N. Jiang, L. Lu, H.-J. Zhang, J.-H. Tao, and L.-H. Cai, "Music type classification by spectral contrast feature," in IEEE International Conference on Multimedia and Expo (ICME’02), 2002, vol. 1, pp. 113–116.
[2] V. Akkermans, J. Serrà, and P. Herrera, "Shape-based spectral contrast descriptor," in Sound and Music Computing Conference (SMC’09), 2009, pp. 143–148.
Category: Spectral 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
= 'SpectralContrast'
$category
protected
string
$category
= 'Spectral'
$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