bob.machine.JFAMachine

class bob.machine.JFAMachine((object)self, (JFABase)jfa_base) → None :

Bases: bob.machine._machine.MachineGMMStatsScalarBase

A JFAMachine. An attached JFABase should be provided for Joint Factor Analysis. The JFAMachine carries information about the speaker factors y and z, whereas a JFABase carries information about the matrices U, V and D.

References: [1] ‘Explicit Modelling of Session Variability for Speaker Verification’, R. Vogt, S. Sridharan, Computer Speech & Language, 2008, vol. 22, no. 1, pp. 17-38 [2] ‘Session Variability Modelling for Face Authentication’, C. McCool, R. Wallace, M. McLaren, L. El Shafey, S. Marcel, IET Biometrics, 2013

Builds a new JFAMachine.

__init__( (object)self) -> None :
Constructs a 1x1 JFAMachine instance. You have to set a JFABase afterwards.
__init__( (object)self, (HDF5File)config) -> None :
Constructs a new JFAMachine from a configuration file.
__init__( (object)self, (JFAMachine)machine) -> None :
Copy constructs a JFAMachine
__init__((object)self, (JFABase)jfa_base) → None :

Builds a new JFAMachine.

__init__( (object)self) -> None :
Constructs a 1x1 JFAMachine instance. You have to set a JFABase afterwards.
__init__( (object)self, (HDF5File)config) -> None :
Constructs a new JFAMachine from a configuration file.
__init__( (object)self, (JFAMachine)machine) -> None :
Copy constructs a JFAMachine

Methods

__init__((object)self, (JFABase)jfa_base) Builds a new JFAMachine.
estimate_ux((JFAMachine)self, …) Estimates Ux (LPT assumption) given GMM statistics.
estimate_x((JFAMachine)self, …) Estimates the session offset x (LPT assumption) given GMM statistics.
forward((MachineGMMStatsScalarBase)self, …) Executes the machine on the GMMStats, and returns the (scalar) output.
forward_((MachineGMMStatsScalarBase)self, …) Executes the machine on the GMMStats, and returns the (scalar) output.
forward_ux((JFAMachine)self, …) Processes the GMM statistics and Ux to return a score.
is_similar_to((JFAMachine)self, …) Compares this JFABase with the ‘other’ one to be approximately the same.
load((JFAMachine)self, (HDF5File)config) Loads the configuration parameters from a configuration file.
save((JFAMachine)self, (HDF5File)config) Saves the configuration parameters to a configuration file.

Attributes

dim_c The number of Gaussian components
dim_cd The dimensionality of the supervector space
dim_d The dimensionality of the feature space
dim_ru The dimensionality of the within-class variations subspace (rank of U)
dim_rv The dimensionality of the between-class variations subspace (rank of V)
jfa_base The JFABase attached to this machine
x The latent variable x (last one computed).
y The latent variable y of this machine
z The latent variable z of this machine
__call__((MachineGMMStatsScalarBase)self, (GMMStats)input) → float :

Executes the machine on the GMMStats, and returns the (scalar) output. NO CHECK is performed.

dim_c

The number of Gaussian components

dim_cd

The dimensionality of the supervector space

dim_d

The dimensionality of the feature space

dim_ru

The dimensionality of the within-class variations subspace (rank of U)

dim_rv

The dimensionality of the between-class variations subspace (rank of V)

estimate_ux((JFAMachine)self, (GMMStats)stats, (object)ux) → None :

Estimates Ux (LPT assumption) given GMM statistics.

estimate_x((JFAMachine)self, (GMMStats)stats, (object)x) → None :

Estimates the session offset x (LPT assumption) given GMM statistics.

forward((MachineGMMStatsScalarBase)self, (GMMStats)input) → float :

Executes the machine on the GMMStats, and returns the (scalar) output.

forward_((MachineGMMStatsScalarBase)self, (GMMStats)input) → float :

Executes the machine on the GMMStats, and returns the (scalar) output. NO CHECK is performed.

forward_ux((JFAMachine)self, (GMMStats)stats, (object)ux) → float :

Processes the GMM statistics and Ux to return a score.

is_similar_to((JFAMachine)self, (JFAMachine)other[, (float)r_epsilon=1e-05[, (float)a_epsilon=1e-08]]) → bool :

Compares this JFABase with the ‘other’ one to be approximately the same.

jfa_base

The JFABase attached to this machine

load((JFAMachine)self, (HDF5File)config) → None :

Loads the configuration parameters from a configuration file.

save((JFAMachine)self, (HDF5File)config) → None :

Saves the configuration parameters to a configuration file.

x

The latent variable x (last one computed). This is a feature provided for convenience, but this attribute is not ‘part’ of the machine. The session latent variable x is indeed not class-specific, but depends on the sample considered. Furthermore, it is not saved into the machine or used when comparing machines.

y

The latent variable y of this machine

z

The latent variable z of this machine