SpaceVaryingBlur

class deepinv.physics.SpaceVaryingBlur(filters=None, multipliers=None, padding=None, **kwargs)

Bases: LinearPhysics

Implements a space varying blur via product-convolution.

This operator performs

\[y = \sum_{k=1}^K h_k \star (w_k \odot x)\]

where \(\star\) is a convolution, \(\odot\) is a Hadamard product, \(w_k\) are multipliers \(h_k\) are filters.

Parameters:

• w (torch.Tensor) – Multipliers \(w_k\). Tensor of size (b, c, K, H, W). b in {1, B} and c in {1, C}

• h (torch.Tensor) – Filters \(h_k\). Tensor of size (b, c, K, h, w). b in {1, B} and c in {1, C}, h<=H and w<=W.

• padding – options = 'valid', 'circular', 'replicate', 'reflect'. If padding = 'valid' the blurred output is smaller than the image (no padding), otherwise the blurred output has the same size as the image.

• device (str) – cpu or cuda

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Examples:

We show how to instantiate a spatially varying blur operator.

>>> from deepinv.physics.generator import DiffractionBlurGenerator, ProductConvolutionBlurGenerator
>>> from deepinv.physics.blur import SpaceVaryingBlur
>>> from deepinv.utils.plotting import plot
>>> psf_size = 32
>>> img_size = (256, 256)
>>> delta = 16
>>> psf_generator = DiffractionBlurGenerator((psf_size, psf_size))
>>> pc_generator = ProductConvolutionBlurGenerator(psf_generator=psf_generator, img_size=img_size)
>>> params_pc = pc_generator.step(1)
>>> physics = SpaceVaryingBlur(**params_pc)
>>> dirac_comb = torch.zeros(img_size).unsqueeze(0).unsqueeze(0)
>>> dirac_comb[0,0,::delta,::delta] = 1
>>> psf_grid = physics(dirac_comb)
>>> plot(psf_grid, titles="Space varying impulse responses")

A(x: Tensor, filters=None, multipliers=None, padding=None, **kwargs) → Tensor

Applies the space varying blur operator to the input image.

It can receive new parameters \(w_k\), \(h_k\) and padding to be used in the forward operator, and stored as the current parameters.

Parameters:

• filters (torch.Tensor) – Multipliers \(w_k\). Tensor of size (b, c, K, H, W). b in {1, B} and c in {1, C}

• multipliers (torch.Tensor) – Filters \(h_k\). Tensor of size (b, c, K, h, w). b in {1, B} and c in {1, C}, h<=H and w<=W

• padding – options = 'valid', 'circular', 'replicate', 'reflect'. If padding = ‘valid’ the blurred output is smaller than the image (no padding), otherwise the blurred output has the same size as the image.

• device (str) – cpu or cuda

A_adjoint(y: Tensor, filters=None, multipliers=None, padding=None, **kwargs) → Tensor

Applies the adjoint operator.

It can receive new parameters \(w_k\), \(h_k\) and padding to be used in the forward operator, and stored as the current parameters.

Parameters:

• h (torch.Tensor) – Filters \(h_k\). Tensor of size (b, c, K, h, w). b in {1, B} and c in {1, C}, h<=H and w<=W

• w (torch.Tensor) – Multipliers \(w_k\). Tensor of size (b, c, K, H, W). b in {1, B} and c in {1, C}

• padding – options = 'valid', 'circular', 'replicate', 'reflect'. If padding = ‘valid’ the blurred output is smaller than the image (no padding), otherwise the blurred output has the same size as the image.

• device (str) – cpu or cuda

update_parameters(filters=None, multipliers=None, padding=None, **kwargs)

Updates the current parameters.

Parameters:

• filters (torch.Tensor) – Multipliers \(w_k\). Tensor of size (b, c, K, H, W). b in {1, B} and c in {1, C}

• multipliers (torch.Tensor) – Filters \(h_k\). Tensor of size (b, c, K, h, w). b in {1, B} and c in {1, C}, h<=H and w<=W

• padding – options = 'valid', 'circular', 'replicate', 'reflect'.

Examples using SpaceVaryingBlur:

A tour of blur operators

A tour of blur operators