CircularApertureOTFPerturber

class nrtk.impls.perturb_image.pybsm.circular_aperture_otf_perturber.CircularApertureOTFPerturber(sensor: PybsmSensor | None = None, scenario: PybsmScenario | None = None, mtf_wavelengths: Sequence[float] | None = None, mtf_weights: Sequence[float] | None = None, interp: bool = True)

Applies OTF-based image perturbation using a circular aperture model with sensor and scenario configurations.

The CircularApertureOTFPerturber class uses a circular aperture model to simulate image perturbations, allowing for wavelength-specific and sensor-specific modifications based on the sensor and scenario configurations.

See https://pybsm.readthedocs.io/en/latest/explanation.html for image formation concepts and parameter details.

Attributes:

sensor (PybsmSensor | None):

The sensor configuration for the perturbation.

scenario (PybsmScenario | None):

The scenario configuration used for perturbation.

mtf_wavelengths (Sequence[float]):

Sequence of wavelengths used in MTF calculations.

mtf_weights (Sequence[float]):

Sequence of weights associated with each wavelength.

D (float):

Effective aperture diameter.

eta (float):

Relative linear obscuration.

slant_range (float):

Line-of-sight distance between platform and target.

ifov (float):

Instantaneous field of view of the sensor.

interp (bool):

Specifies whether to use interpolated atmospheric data.

Methods

from_config	Instantiate from configuration dictionary.
get_config	Get current configuration including perturber-specific parameters.
get_default_config	Retrieves the default configuration.
get_impls	Discover and return a set of classes that implement the calling class.
get_type_string	Returns the fully qualified type string of the PerturbImage class or its subclass.
is_usable	Check if dependencies are available.
perturb	Apply the OTF-based perturbation to the provided image.

__init__(sensor: PybsmSensor | None = None, scenario: PybsmScenario | None = None, mtf_wavelengths: Sequence[float] | None = None, mtf_weights: Sequence[float] | None = None, interp: bool = True) → None

Initializes the CircularApertureOTFPerturber.

Args:

sensor:

pyBSM sensor object

scenario:

pyBSM scenario object

mtf_wavelengths:

a numpy array of wavelengths (m)

mtf_weights:

a numpy array of weights for each wavelength contribution (arb)

interp:

a boolean determining whether load_database_atmosphere is used with or without interpolation.

If both sensor and scenario parameters are absent, then default values will be used for their parameters

If none of mtf_wavelengths, mtf_weights, sensor or scenario parameters are provided, the values of mtf_wavelengths and mtf_weights will default to [0.50e-6, 0.66e-6] and [1.0, 1.0] respectively

If sensor and scenario parameters are provided, but not mtf_wavelengths and mtf_weights, the values of mtf_wavelengths and mtf_weights will come from the sensor and scenario objects.

If mtf_wavelengths and mtf_weights are provided by the user, those values will be used in the otf calculation.

Raises:

raises ImportError:

If pyBSM is not found, install via pip install nrtk[pybsm].

raises ValueError:

If mtf_wavelengths and mtf_weights are not equal length

raises ValueError:

If mtf_wavelengths is empty or mtf_weights is empty

get_config() → dict[str, Any]

Get current configuration including perturber-specific parameters.