LION.operatorsΒΆ

LION operators.

The generic ones are here; each kind of operator has its own folder, with its parameters, operator and reconstructions: LION.operators.ct (computed tomography) and LION.operators.pcm (photocurrent mapping).

Modules

CompositeOp(wavelet, phi[, device])

The composite operator A = Phi Psi^-1 and its adjoint: the measurement operator phi (e.g. photocurrent mapping's, LION.operators.pcm.PhotocurrentMapOp) applied to the image of wavelet coefficients (wavelet, a Wavelet2D), for sparse recovery in the wavelet domain (Koutsourakis, Thompson and Blakesley, "Toward Megapixel Resolution Compressed Sensing Current Mapping of Photovoltaic Devices Using Digital Light Processing", Solar RRL 5(11):2100467, 2021, doi:10.1002/solr.202100467).

DebiasOp(op, y, w[, support_tol])

The forward operator operator restricted to the support of w (an l1 minimiser; its entries above support_tol), for debiasing it by least squares on that support (Koutsourakis, Thompson and Blakesley, "Toward Megapixel Resolution Compressed Sensing Current Mapping of Photovoltaic Devices Using Digital Light Processing", Solar RRL 5(11):2100467, 2021, doi:10.1002/solr.202100467.) y: the measurements (M,).

Operator([device])

The base class of LION's operators: a linear map, as a torch module, with its adjoint and the shapes it maps between.

Wavelet2D(shape[, wavelet_name, level, ...])

The 2D orthogonal wavelet transform (PyWavelets) of images of shape (H, W), as an operator: images to a flat vector of coefficients.

ct

Computed tomography: the geometry (the CT operator's parameters), the projection operator, noise and HU conversions, and CT reconstructions.

pcm

Photocurrent mapping: the photocurrent mapping operator, its subsampling, and the Walsh-Hadamard transform it uses.