ImageDenoiserClassic - Classic Image Denoiser

ImageDenoiserClassic

Procedural calibration and denoising API:

Bilateral

aydin.it.classic_denoisers.bilateral.denoise_bilateral(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], sigma_color: Optional[float] = None, sigma_spatial: float = 1, bins: int = 10000, **kwargs)

Denoises the given image using a <a href=”https://en.wikipedia.org/wiki/Bilateral_filter”>bilateral filter</a>. The bilateral filter is a edge-preserving smoothing filter that can be used for image denoising. Each pixel value is replaced by a weighted average of intensity values from nearby pixels. The weighting is inversely related to the pixel distance in space but also in the pixels value differences.

Parameters

imageArrayLike

Image to denoise

sigma_colorfloat

Standard deviation for grayvalue/color distance (radiometric similarity). A larger value results in averaging of pixels with larger radiometric differences. Note, that the image will be converted using the img_as_float function and thus the standard deviation is in respect to the range [0, 1]. If the value is None the standard deviation of the image will be used.

sigma_spatialfloat

Standard deviation for range distance. A larger value results in averaging of pixels with larger spatial differences.

binsint

Number of discrete values for Gaussian weights of color filtering. A larger value results in improved accuracy.

kwargs: dict

Other parameters

Returns

Denoised image

BMND

Butterworth

aydin.it.classic_denoisers.butterworth.calibrate_denoise_butterworth(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], mode: str = 'full', axes: Optional[Tuple[int, ...]] = None, other_filters: bool = False, min_padding: int = 2, max_padding: int = 32, min_freq: float = 1e-09, max_freq: float = 1.0, frequency_tolerance: float = 0.05, min_order: float = 1.0, max_order: float = 8.0, crop_size_in_voxels: Optional[int] = 1000000, optimiser: str = 'fast', max_num_evaluations: int = 256, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', multi_core: bool = True, display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Butterworth denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate Butterworth denoiser for.

mode: str

Possible modes are: ‘isotropic’ for isotropic, meaning only one frequency cut-off is calibrated for all axes , ‘z-yx’ (or ‘xy-z’) for 3D stacks where the cut-off frequency for the x and y axes is the same but different for the z axis, ‘t-z-yx’ (or ‘xy-z-t’) for 3D+t timelapse where the cut-off frequency for the x and y axes is the same but different for the z and t axis, and ‘full’ for which all frequency cut-offs are different. Use ‘z-yx’ or ‘t-z-yx’ for axes are ordered as: t, z, y and then x which is the default. If for some reason the axis order is reversed you can use ‘xy-z’ or ‘xy-z-t’. Note: for 2D+t timelapses where the resolution over x and y are expected to be the same, simply use: ‘z-yx’ (or ‘xy-z’).

axes: Optional[Tuple[int,…]]

Axes over which to apply low-pass filtering. (advanced)

other_filters: bool

if True other filters similar to Butterworth are tried such as Type II Chebyshev filter.

min_padding: int

Minimum amount of padding to be added to avoid edge effects. (advanced)

max_padding: int

Maximum amount of padding to be added to avoid edge effects. (advanced)

min_freq: float

Minimum cutoff frequency to use for calibration. Must be within [0,1], typically close to zero. (advanced)

max_freq: float

Maximum cutoff frequency to use for calibration. Must be within [0,1], typically close to one. (advanced)

frequency_tolerance: float

Frequency tolerance within [-1,1]. A positive value lets more high-frequencies to go through the low-pass, negative values bring down the cut-off frequencies, zero has no effect. Positive values reduces the effect of denoising but also lead to conservative filtering that avoids removing potentially important information at the boundary (in frequency space) between signal and noise. This can also improve the appearance of the images by avoiding the impression that the images have been ‘over-blurred’. Increase this value by small steps of 0.05 to reduce blurring if the image seems too fuzzy.

min_order: float

Minimal order for the Butterworth filter to use for calibration. (advanced)

max_order: float

Maximal order for the Butterworth filter to use for calibration. If min_order==max_order then no search is performed for the filter’s order. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 256000, 320000, 1’000’000, 2’000’000. We do not recommend values higher than 3000000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: Optional[List[Tuple[int]]]

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

multi_core: bool

Use all CPU cores during calibration. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters. (advanced)

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.butterworth.denoise_butterworth(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], axes: Optional[Tuple[int, ...]] = None, filter_type: str = 'butterworth', freq_cutoff: Union[float, Sequence[float]] = 0.5, order: float = 5, min_padding: int = 2, max_padding: int = 32, multi_core: bool = True)

Denoises the given image by applying a configurable <a href=”https://en.wikipedia.org/wiki/Butterworth_filter”>Butterworth lowpass filter</a>. Remarkably good when your signal does not have high-frequencies beyond a certain cutoff frequency. This is probably the first algorithm that should be tried of all currently available in Aydin. It is actually quite impressive how well this performs in practice. If the signal in your images is band-limited as is often the case for microscopy images, this denoiser will work great.

Note: We recommend applying a variance stabilisation transform to improve results for images with non-Gaussian noise.

Parameters

image: ArrayLike

Image to be denoised

axes: Optional[Tuple[int,…]]

Axes over which to apply lowpass filtering.

filter_type: str

Type of filter. The default is ‘butterworth’ but we have now introduced another filter type: ‘chebyshev2’ which is a Type II Chebyshev filter with a steeper cut-off than Butterworth at the cost of some ripples in the rejected high frequencies. (advanced)

freq_cutoff: Union[float, Sequence[float]]

Single or sequence cutoff frequency, must be within [0, 1]

order: float

Filter order, typically an integer above 1.

min_padding: int

Minimum amount of padding to be added to avoid edge effects.

max_padding: int

Maximum amount of padding to be added to avoid edge effects.

multi_core: bool

By default we use as many cores as possible, in some cases, for small (test) images, it might be faster to run on a single core instead of starting the whole parallelization machinery.

Returns

Denoised image

Dictionary fixed

Dictionary learned

aydin.it.classic_denoisers.dictionary_learned.calibrate_denoise_dictionary_learned(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], patch_size: Optional[int] = None, try_omp: bool = True, try_lasso_lars: bool = False, try_lasso_cd: bool = False, try_lars: bool = False, try_threshold: bool = False, max_patches: Optional[int] = 1000000, dictionary_size: Optional[int] = None, over_completeness: float = 3, max_dictionary_size: int = 256, try_kmeans: bool = True, try_pca: bool = True, try_ica: bool = False, try_sdl: bool = False, num_sparsity_values_to_try: int = 6, optimiser: str = 'fast', num_iterations: int = 1024, batch_size: int = 3, alpha: int = 1, do_cleanup_dictionary: bool = True, do_denoise_dictionary: bool = False, crop_size_in_voxels: Optional[int] = 96000, max_num_evaluations: int = 128, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', display_dictionary: bool = False, display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the dictionary-based denoiser for the given image by finding the best learned dictionary of patches and returns the optimal parameters.

Parameters

imageArrayLike

Image to calibrate denoiser for.

patch_sizeint

Patch size. If None it is automatically adjusted to teh number of dimensions of the image to ensure a reasonable computational effort. (advanced)

try_omp: bool

Whether OMP should be tried as a sparse coding algorithm during calibration.

try_lasso_lars: bool

Whether LASSO-LARS should be tried as a sparse coding algorithm during calibration.

try_lasso_cd: bool

Whether LASSO-CD should be tried as a sparse coding algorithm during calibration.

try_lars: bool

Whether LARS should be tried as a sparse coding algorithm during calibration.

try_threshold: bool

Whether ‘threshold’’ should be tried as a sparse coding algorithm during calibration.

max_patches: Optional[int]

Max number of patches to extract for dictionary learning. If None there is no limit. (advanced)

dictionary_size: int

Dictionary size in ‘atoms’. If None the dictionary size is inferred from the over_completeness parameter type. (advanced)

over_completeness: float

Given a certain patch size p and image dimension n, a complete basis has p^n elements, the over completeness factor determines the size of the dictionary relative to that by the formula: ox*p^n. (advanced)

max_dictionary_size: int

Independently of any other parameter, we limit the size of the dictionary to this provided number. (advanced)

try_kmeans: bool

Whether to compute a kmeans based dictionary and used it as one of possible dictionaries during calibration.

try_pca: bool

Whether to compute a PCA based dictionary and used it as one of possible dictionaries during calibration.

try_ica: bool

Whether to compute an ICA (Independent Component Analysis) based dictionary and used it as one of possible dictionaries during calibration.

try_sdl: bool

Whether to compute a SDL (Sparse Dictionary Learning) based dictionary and used it as one of possible dictionaries during calibration.

num_sparsity_values_to_try: int

Maximum number of sparsity values to try during calibration (advanced)

num_iterations: int

Number of iterations for learning dictionary. (advanced)

batch_size: int

Size of batches during batched dictionary learning. (advanced)

alpha: int

Sparsity prior strength. (advanced)

do_cleanup_dictionary: bool

Removes dictionary entries that are likely pure noise or have impulses or very high-frequencies or checkerboard patterns that are unlikely needed to reconstruct the true signal. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_dictionary: bool

If True displays dictionary with napari – for debug purposes. (advanced) (hidden)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.dictionary_learned.denoise_dictionary_learned(*args, **kwargs)

Denoises the given image using sparse-coding over a fixed dictionary of nD image patches. The dictionary learning and patch sparse coding uses scikit-learn’s Batch-OMP implementation.

Parameters

args

kwargs

Returns

denoised image

Gaussian

aydin.it.classic_denoisers.gaussian.calibrate_denoise_gaussian(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], axes: Optional[Tuple[int, ...]] = None, min_sigma: float = 1e-06, max_sigma: float = 2.0, crop_size_in_voxels: Optional[int] = 128000, optimiser: str = 'fast', max_num_evaluations: int = 512, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'median', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Gaussian denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate denoiser for.

axes: Optional[Tuple[int,…]]

Axes over which to apply low-pass filtering. (advanced)

min_sigma: float

Minimum sigma for Gaussian filter. (advanced)

max_sigma: float

Maximum sigma for Gaussian filter.

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.gaussian.denoise_gaussian(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], axes: Optional[Tuple[int, ...]] = None, sigma: float = 1.0, truncate: float = 4.0, **kwargs)

Denoises the given image using a simple Gaussian filter. Difficult to beat in terms of speed and often provides sufficient although not superb denoising performance. You should always try simple and fast denoisers first, and see if that works for you. If it works and is sufficient for your needs, why go for slower and more complex and slower approach? The only weakness of gaussian filtering is that it affects all frequencies. In contrast, the auto-tuned Butterworth denoiser will not blur within the estimated band-pass of the signal. Thus we recommend you use the Butterworth denoiser instead unless you have a good reason to use this one.

Note: We recommend applying a variance stabilisation transform to improve results for images with non-Gaussian noise.

Parameters

image: ArrayLike

nD image to denoise

axes: Optional[Tuple[int,…]]

Axes over which to apply low-pass filtering. (advanced)

sigma: float

Standard deviation for Gaussian kernel.

truncate: float

Truncate the filter at this many standard deviations.

Returns

Denoised image

Gaussian-Median

aydin.it.classic_denoisers.gm.calibrate_denoise_gm(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], max_filter_size: int = 3, crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'fast', max_num_evaluations: int = 256, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'median', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Gaussian-Median mix denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate denoiser for.

max_filter_sizeint

Max filter size to use during calibration. Should be a positive odd number such as 3, 5, 7, …

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.gm.denoise_gm(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], sigma: float = 0.5, size: int = 3, factor: float = 2, alpha: float = 0.25, beta: float = 0.3, gamma: float = 0.5, **kwargs)

Denoises the given image with a linear mixing of median filtering and Gaussian filtering. Simple and fast but quite effective for low to moderate noise levels and images with band-limited signal (~ there is a ‘PSF’).

Note: We recommend applying a variance stabilisation transform to improve results for images with non-Gaussian noise.

Parameters

image: ArrayLike

Image to be denoised.

sigma: float

Gaussian blur sigma.

size: int

Size of the median filter

factor: float

Ratio between the scales of the two scales

alpha: float

First mixing coefficient.

beta: float

First mixing coefficient.

gamma: float

First mixing coefficient.

Returns

Denoised image

Harmonic

aydin.it.classic_denoisers.harmonic.calibrate_denoise_harmonic(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], rank: bool = False, crop_size_in_voxels: Optional[int] = 256000, optimiser: str = 'fast', max_num_evaluations: int = 16, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Harmonic denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate denoiser for.

rank: bool

If true, uses a better estimate of min and max filters using a rank filter, may be much slower. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.harmonic.denoise_harmonic(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], filter: str = 'uniform', rank: bool = False, max_iterations: int = 1024, epsilon: float = 1e-08, alpha: float = 0.5, step: float = 0.1, max_gradient: float = 32, **kwargs)

Denoises the given image by applying a non-linear <a href=”https://en.wikipedia.org/wiki/Harmonic_function”>harmonic</a> prior. The gradient of the prior term is a laplace-like operator that is scaled with the range of values around the pixel. One of its specificities is that it is very effective at smoothing uniform regions of an image.

Note: Works well in practice, but a bit slow as currently implemented for large images.

Parameters

image: ArrayLike

Image to be denoised

filter: str

Type of filter used to compute the Laplace-like prior. Can be either ‘uniform’, ‘gaussian’ or ‘median’.

rank: bool

Uses a more robust estimation of the range.

max_iterations: int

Max number of iterations.

epsilon: float

Small value used to determine convergence.

alpha: float

Balancing between data and prior term. A value of 0 favours the prior entirely, whether a value of 1 favours the data term entirely.

step: float

Starting step used for gradient descent

max_gradient: float

Maximum gradient tolerated – usefull to avoid ‘numerical explosions’ ;-)

Returns

Denoised image

Lipschitz

aydin.it.classic_denoisers.lipschitz.calibrate_denoise_lipschitz(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], lipschitz: float = 0.1, percentile: float = 0.001, alpha: float = 0.1, max_num_iterations: int = 256, blind_spots: Optional[List[Tuple[int]]] = None, **other_fixed_parameters)

Calibrates the Lipschitz denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate Sobolev denoiser for.

lipschitzfloat

Increase to tolerate more variation, decrease to be more aggressive in removing salt & pepper noise.

percentilefloat

Percentile value used to determine the threshold for choosing the worst offending voxels per iteration. (advanced)

alphafloat

This constant controls the amount of correction per iteration. Should be a number within[0, 1]. (advanced)

max_num_iterations: int

Maximum number of Lipschitz correction iterations to run. (advanced)

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters. (advanced)

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.lipschitz.denoise_lipschitz(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], lipschitz: float = 0.05, percentile: float = 0.01, alpha: float = 0.1, max_num_iterations: int = 128, multi_core: bool = True)

Denoises the given image by correcting voxel values that violate <a href=”https://en.wikipedia.org/wiki/Lipschitz_continuity”>Lipschitz continuity</a> criterion. These voxels get replaced iteratively replaced by the median. This is repeated for a number of iterations (max_num_iterations), until no more changes to the image occurs, and making sure that the proportion of corrected voxels remains below a given level (max_corrections argument).

Parameters

image: ArrayLike

Image to be denoised

lipschitzfloat

Increase to tolerate more variation, decrease to be more aggressive in removing impulse/salt&pepper noise.

percentilefloat

Percentile value used to determine the threshold for choosing the worst offending voxels per iteration. (advanced)

alphafloat

This constant controls the amount of correction per ietartion. Should be a number within[0, 1]. (advanced)

max_num_iterations: int

Maximum number of Lipschitz correction iterations to run. (advanced)

multi_core: bool

By default we use as many cores as possible, in some cases, for small (test) images, it might be faster to run on a single core instead of starting the whole parallelization machinery. (advanced)

Returns

Denoised image

Non-Local Means(NLM)

aydin.it.classic_denoisers.nlm.calibrate_denoise_nlm(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], patch_size: int = 7, patch_distance: int = 11, crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'fast', max_num_evaluations: int = 256, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Non-Local Means (NLM) denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate denoiser for.

patch_sizeint, optional

Size of patches used for denoising. (advanced)

patch_distanceint, optional

Maximal distance in pixels where to search patches used for denoising. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.nlm.denoise_nlm(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], patch_size: int = 7, patch_distance: int = 11, cutoff_distance: float = 0.1, sigma=0.0)

Denoise given image using either scikit-image implementation of <a href=”https://en.wikipedia.org/wiki/Non-local_means”>Non-Local-Means (NLM)</a>.

Parameters

imageArayLike

Image to be denoised

patch_sizeint, optional

Size of patches used for denoising.

patch_distanceint, optional

Maximal distance in pixels where to search patches used for denoising.

cutoff_distancefloat, optional

Cut-off distance (in gray levels). The higher h, the more permissive one is in accepting patches. A higher h results in a smoother image, at the expense of blurring features. For a Gaussian noise of standard deviation sigma, a rule of thumb is to choose the value of h to be sigma of slightly less.

sigmafloat, optional

The standard deviation of the (Gaussian) noise. If provided, a more robust computation of patch weights is computed that takes the expected noise variance into account (see Notes below).

Returns

Denoised image as ndarray.

PCA

aydin.it.classic_denoisers.pca.calibrate_denoise_pca(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], patch_size: Optional[Union[int, Tuple[int], str]] = None, crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'fast', max_num_evaluations: int = 16, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', multi_core: bool = True, display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Principal Component Analysis (PCA) denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate spectral denoiser for.

patch_size: int

Patch size for the ‘image-to-patch’ transform. Can be an int s that corresponds to isotropic patches of shape: (s,)*image.ndim, or a tuple of ints. By default (None) the patch size is chosen automatically to give the best results. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

multi_core: bool

Use all CPU cores during calibration. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.pca.denoise_pca(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], patch_size: Optional[Union[int, Tuple[int]]] = None, threshold: float = 0.1, reconstruction_gamma: float = 0, multi_core: bool = True)

Denoises the given image by first applying the patch transform, and then doing a PCA projection of these patches along the first components. The cut-off is set by a threshold parameter.

Parameters

image: ArrayLike

Image to denoise

patch_size: int

Patch size for the ‘image-to-patch’ transform. Can be: ‘full’ for a single patch covering the whole image, ‘half’, ‘quarter’, or an int s that corresponds to isotropic patches of shape: (s,)*image.ndim, or a tuple of ints. By default (None) the patch size is chosen automatically to give the best results.

threshold: float

Threshold for proportion of components to retain. Between 0 and 1

reconstruction_gamma: float

Patch reconstruction parameter

multi_core: bool

By default we use as many cores as possible, in some cases, for small (test) images, it might be faster to run on a single core instead of starting the whole parallelization machinery.

Returns

Denoised image

Spectral

aydin.it.classic_denoisers.spectral.calibrate_denoise_spectral(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], axes: Optional[Tuple[int, ...]] = None, patch_size: Optional[Union[int, Tuple[int], str]] = None, try_dct: bool = True, try_fft: bool = False, try_dst: bool = False, max_order: float = 6.0, crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'fast', max_num_evaluations: int = 128, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', multi_core: bool = True, display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Spectral denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Parameters

image: ArrayLike

Image to calibrate spectral denoiser for.

axes: Optional[Tuple[int,…]]

Axes over which to apply the spectral transform (dct, dst, fft) for denoising each patch.

patch_size: int

Patch size for the ‘image-to-patch’ transform. Can be: ‘full’ for a single patch covering the whole image, ‘half’, ‘quarter’, or an int s that corresponds to isotropic patches of shape: (s,)*image.ndim, or a tuple of ints. By default (None) the patch size is chosen automatically to give the best results. (advanced)

try_dct: bool

Tries DCT transform during optimisation.

try_fft: bool

Tries FFT transform during optimisation.

try_dst: bool

Tries DST ransform during optimisation.

max_order: float

Maximal order for the Butterworth filter. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

multi_core: bool

Use all CPU cores during calibration. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.spectral.denoise_spectral(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], axes: Optional[Tuple[int, ...]] = None, patch_size: Optional[Union[int, Tuple[int], str]] = None, mode: str = 'dct', threshold: float = 0.5, freq_bias_stength: float = 1, freq_cutoff: Union[float, Sequence[float]] = 0.5, order: float = 1, reconstruction_gamma: float = 0, multi_core: bool = True)

Denoises the given image by first applying the patch transform, and then zeroing Fourier/DCT/DST coefficients below a given threshold. In addition, we apply Butterworth filter to suppress frequencies above the band-pass and a configurable frequency bias before applying the thresholding to favour suppressing high versus low frequencies.

Note: This seems like a lot of parameters, but thanks to our auto-tuning approach these parameters are all automatically determined 😊.

Parameters

image: ArrayLike

Image to denoise

axes: Optional[Tuple[int,…]]

Axes over which to apply the spetcral transform (dct, dst, fft) for denoising each patch.

patch_size: int

Patch size for the ‘image-to-patch’ transform. Can be: ‘full’ for a single patch covering the whole image, ‘half’, ‘quarter’, or an int s that corresponds to isotropic patches of shape: (s,)*image.ndim, or a tuple of ints. By default (None) the patch size is chosen automatically to give the best results.

mode: str

Possible modes are: ‘dct’(works best!), ‘dst’, and ‘fft’.

threshold: float

Threshold between 0 and 1

freq_bias_stength: float

Frequency bias: closer to zero: no bias against high frequencies, closer to one and above: stronger bias towards high-frequencies.

freq_cutoff: float

Cutoff frequency, must be within [0, 1]. In addition

order: float

Filter order, typically an integer above 1.

reconstruction_gamma: float

Patch reconstruction parameter

multi_core: bool

By default we use as many cores as possible, in some cases, for small (test) images, it might be faster to run on a single core instead of starting the whole parallelization machinery.

Returns

Denoised image

Total Variation(TV)

aydin.it.classic_denoisers.tv.calibrate_denoise_tv(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], enable_mixing: bool = True, crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'fast', max_num_evaluations: int = 512, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates the Total Variation (TV) denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Note: we use the scikt-image implementation of TV denoising.

Parameters

image: ArrayLike

Image to calibrate TV denoiser for.

enable_mixing: bool

TV denoising tends to return very non-natural looking piece-wise constant images. To mitigate this we give the option to mix a bit of the original image denoised with a Gaussian filter. The sigma for the Gaussian filter is also calibrated. Note: In some cases it might be simply better to not use the TV denoised image and instead just use the Gaussian-filter-denoised image, check the “beta” parameter during optimisation, if that number is very close to 1.0 then you know you should probably use a Butterworth or Gaussian denoiser.

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function, dictionary containing optimal parameters,

and free memory needed in bytes for computation.

aydin.it.classic_denoisers.tv.denoise_tv(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], algorithm: str = 'bregman', weight: float = 1, alpha: float = 1.0, beta: float = 0.0, sigma: float = 0.0, **kwargs)

Denoises the given image using either scikit-image implementation of Bregman or Chambolle <a href=”https://en.wikipedia.org/wiki/Total_variation_denoising”>Total Variation (TV) denoising</a>. We attempt to rescale the weight parameter to obtain similar results between Bregman and Chambolle for the same weight.

Note: Because of limitations of the current scikit-image implementation, if an image with more than 2 dimensions is passed, we use the Chambolle implementation as it supports nD images…

Parameters

image: ArrayLike

Image to denoise

algorithm: str

Algorithm to apply: either ‘bregman’ or ‘chambolle’

weight: float

Weight to balance data term versus prior term. Larger values correspond to a stronger prior during optimisation, and thus more aggressive denoising

alpha: float

TV denoising tends to return images that are dimmer, we have the option of pushing the brightness here..

beta: float

TV denoising tends to return very non-natural looking images, here we give the option to ‘mix-in’ back a bit of the original image denoised with a gaussian filter.

sigma: float

Sigma for gaussian filtered image that is mixed with the TV denoised image.

kwargs

Any other parameters to be passed to scikit-image implementations

Returns

Denoised image

Wavelet

aydin.it.classic_denoisers.wavelet.calibrate_denoise_wavelet(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], all_wavelets: bool = False, wavelet_name_filter: str = '', crop_size_in_voxels: Optional[int] = 96000, optimiser: str = 'smart', max_num_evaluations: int = 256, blind_spots: Optional[List[Tuple[int]]] = None, jinv_interpolation_mode: str = 'gaussian', display_images: bool = False, display_crop: bool = False, **other_fixed_parameters)

Calibrates a <a href=”https://en.wikipedia.org/wiki/Wavelet_transform “>wavelet</a> denoiser for the given image and returns the optimal parameters obtained using the N2S loss.

Note: we use the scikt-image implementation of wavelet denoising.

Parameters

image: ArrayLike

Image to calibrate wavelet denoiser for.

all_wavelets: bool

If true then all wavelet transforms are tried during calibration, otherwise only a selection that we consider to be the best. Note: trying all transforms can take a long time but might find the magical transform that will make it work for your data. (advanced)

wavelet_name_filter: str

Comma separated list of wavelet name substrings. We only keep for calibration wavelets which name contains these substrings. Best used when using all transforms as starting list to select a family of wavelets, or to select a specific one by providing its name in full. (advanced)

crop_size_in_voxels: int or None for default

Number of voxels for crop used to calibrate denoiser. Increase this number by factors of two if denoising quality is unsatisfactory – this can be important for very noisy images. Values to try are: 65000, 128000, 256000, 320000. We do not recommend values higher than 512000.

optimiser: str

Optimiser to use for finding the best denoising parameters. Can be: ‘smart’ (default), or ‘fast’ for a mix of SHGO followed by L-BFGS-B. (advanced)

max_num_evaluations: int

Maximum number of evaluations for finding the optimal parameters. Increase this number by factors of two if denoising quality is unsatisfactory.

blind_spots: bool

List of voxel coordinates (relative to receptive field center) to be included in the blind-spot. For example, you can give a list of 3 tuples: [(0,0,0), (0,1,0), (0,-1,0)] to extend the blind spot to cover voxels of relative coordinates: (0,0,0),(0,1,0), and (0,-1,0) (advanced) (hidden)

jinv_interpolation_mode: str

J-invariance interpolation mode for masking. Can be: ‘median’ or ‘gaussian’. (advanced)

display_images: bool

When True the denoised images encountered during optimisation are shown. (advanced) (hidden)

display_crop: bool

Displays crop, for debugging purposes… (advanced) (hidden)

other_fixed_parameters: dict

Any other fixed parameters

Returns

Denoising function and dictionary containing optimal parameters.

aydin.it.classic_denoisers.wavelet.denoise_wavelet(image: Union[numpy._typing._array_like._SupportsArray[numpy.dtype], numpy._typing._nested_sequence._NestedSequence[numpy._typing._array_like._SupportsArray[numpy.dtype]], bool, int, float, complex, str, bytes, numpy._typing._nested_sequence._NestedSequence[Union[bool, int, float, complex, str, bytes]]], wavelet: str = 'db1', sigma: Optional[float] = None, mode: str = 'soft', method: str = 'BayesShrink', **kwargs)

Denoises the given image using the scikit-image implementation of <a href=”https://en.wikipedia.org/wiki/Wavelet_transform “> wavelet</a> denoising.

Note: we use the scikt-image implementation of wavelet denoising.

Parameters

image: ArrayLike

Image to denoise

waveletstring, optional

The type of wavelet to perform and can be any of the options pywt.wavelist outputs. The default is ‘db1’. For example, wavelet can be any of {'db2', 'haar', 'sym9'} and many more (see PyWavelets documentation).

sigmafloat or list, optional

The noise standard deviation used when computing the wavelet detail coefficient threshold(s). When None (default), the noise standard deviation is estimated via the method in (2)_.

mode{‘soft’, ‘hard’}, optional

An optional argument to choose the type of denoising performed. It noted that choosing soft thresholding given additive noise finds the best approximation of the original image.

method{‘BayesShrink’, ‘VisuShrink’}, optional

Thresholding method to be used. The currently supported methods are “BayesShrink” (1)_ and “VisuShrink” (2)_. Defaults to “BayesShrink”.

kwargsdict

Any other parameters to be passed to scikit-image implementations

Returns

Denoised image as ndarray