Esempio n. 1
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    def test_compare_with_PDHG(self):
        # Load an image from the CIL gallery.
        data = dataexample.SHAPES.get()
        ig = data.geometry
        # Add gaussian noise
        noisy_data = applynoise.gaussian(data, seed=10, var=0.005)

        # TV regularisation parameter
        alpha = 1

        # fidelity = 0.5 * L2NormSquared(b=noisy_data)
        # fidelity = L1Norm(b=noisy_data)
        fidelity = KullbackLeibler(b=noisy_data, use_numba=False)

        # Setup and run the PDHG algorithm
        F = BlockFunction(alpha * MixedL21Norm(), fidelity)
        G = ZeroFunction()
        K = BlockOperator(GradientOperator(ig), IdentityOperator(ig))

        # Compute operator Norm
        normK = K.norm()

        # Primal & dual stepsizes
        sigma = 1. / normK
        tau = 1. / normK

        pdhg = PDHG(f=F,
                    g=G,
                    operator=K,
                    tau=tau,
                    sigma=sigma,
                    max_iteration=100,
                    update_objective_interval=10)
        pdhg.run(verbose=0)

        sigma = 1
        tau = sigma / normK**2

        admm = LADMM(f=G,
                     g=F,
                     operator=K,
                     tau=tau,
                     sigma=sigma,
                     max_iteration=100,
                     update_objective_interval=10)
        admm.run(verbose=0)

        from cil.utilities.quality_measures import psnr
        if debug_print:
            print("PSNR", psnr(admm.solution, pdhg.solution))
        np.testing.assert_almost_equal(psnr(admm.solution, pdhg.solution),
                                       84.46678222768597,
                                       decimal=4)
Esempio n. 2
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    def test_SPDHG_vs_PDHG_explicit(self):
        data = dataexample.SIMPLE_PHANTOM_2D.get(size=(128, 128))

        ig = data.geometry
        ig.voxel_size_x = 0.1
        ig.voxel_size_y = 0.1

        detectors = ig.shape[0]
        angles = np.linspace(0, np.pi, 180)
        ag = AcquisitionGeometry('parallel',
                                 '2D',
                                 angles,
                                 detectors,
                                 pixel_size_h=0.1,
                                 angle_unit='radian')
        # Select device
        dev = 'cpu'

        Aop = AstraProjectorSimple(ig, ag, dev)

        sin = Aop.direct(data)
        # Create noisy data. Apply Gaussian noise
        noises = ['gaussian', 'poisson']
        noise = noises[1]
        if noise == 'poisson':
            scale = 5
            noisy_data = scale * applynoise.poisson(sin / scale, seed=10)
            # np.random.seed(10)
            # scale = 5
            # eta = 0
            # noisy_data = AcquisitionData(np.random.poisson( scale * (eta + sin.as_array()))/scale, ag)
        elif noise == 'gaussian':
            noisy_data = noise.gaussian(sin, var=0.1, seed=10)
            # np.random.seed(10)
            # n1 = np.random.normal(0, 0.1, size = ag.shape)
            # noisy_data = AcquisitionData(n1 + sin.as_array(), ag)

        else:
            raise ValueError('Unsupported Noise ', noise)

        #%% 'explicit' SPDHG, scalar step-sizes
        subsets = 10
        size_of_subsets = int(len(angles) / subsets)
        # create Gradient operator
        op1 = GradientOperator(ig)
        # take angles and create uniform subsets in uniform+sequential setting
        list_angles = [
            angles[i:i + size_of_subsets]
            for i in range(0, len(angles), size_of_subsets)
        ]
        # create acquisitioin geometries for each the interval of splitting angles
        list_geoms = [
            AcquisitionGeometry('parallel',
                                '2D',
                                list_angles[i],
                                detectors,
                                pixel_size_h=0.1,
                                angle_unit='radian')
            for i in range(len(list_angles))
        ]
        # create with operators as many as the subsets
        A = BlockOperator(*[
            AstraProjectorSimple(ig, list_geoms[i], dev)
            for i in range(subsets)
        ] + [op1])
        ## number of subsets
        #(sub2ind, ind2sub) = divide_1Darray_equally(range(len(A)), subsets)
        #
        ## acquisisiton data
        ## acquisisiton data
        AD_list = []
        for sub_num in range(subsets):
            for i in range(0, len(angles), size_of_subsets):
                arr = noisy_data.as_array()[i:i + size_of_subsets, :]
                AD_list.append(
                    AcquisitionData(arr, geometry=list_geoms[sub_num]))

        g = BlockDataContainer(*AD_list)
        alpha = 0.5
        ## block function
        F = BlockFunction(*[
            *[KullbackLeibler(b=g[i])
              for i in range(subsets)] + [alpha * MixedL21Norm()]
        ])
        G = IndicatorBox(lower=0)

        prob = [1 / (2 * subsets)] * (len(A) - 1) + [1 / 2]
        spdhg = SPDHG(f=F,
                      g=G,
                      operator=A,
                      max_iteration=1000,
                      update_objective_interval=200,
                      prob=prob)
        spdhg.run(1000, verbose=0)

        #%% 'explicit' PDHG, scalar step-sizes
        op1 = GradientOperator(ig)
        op2 = Aop
        # Create BlockOperator
        operator = BlockOperator(op1, op2, shape=(2, 1))
        f2 = KullbackLeibler(b=noisy_data)
        g = IndicatorBox(lower=0)
        normK = operator.norm()
        sigma = 1 / normK
        tau = 1 / normK

        f1 = alpha * MixedL21Norm()
        f = BlockFunction(f1, f2)
        # Setup and run the PDHG algorithm
        pdhg = PDHG(f=f, g=g, operator=operator, tau=tau, sigma=sigma)
        pdhg.max_iteration = 1000
        pdhg.update_objective_interval = 200
        pdhg.run(1000, verbose=0)

        #%% show diff between PDHG and SPDHG
        # plt.imshow(spdhg.get_output().as_array() -pdhg.get_output().as_array())
        # plt.colorbar()
        # plt.show()

        from cil.utilities.quality_measures import mae, mse, psnr
        qm = (mae(spdhg.get_output(),
                  pdhg.get_output()), mse(spdhg.get_output(),
                                          pdhg.get_output()),
              psnr(spdhg.get_output(), pdhg.get_output()))
        if debug_print:
            print("Quality measures", qm)
        np.testing.assert_almost_equal(mae(spdhg.get_output(),
                                           pdhg.get_output()),
                                       0.00150,
                                       decimal=3)
        np.testing.assert_almost_equal(mse(spdhg.get_output(),
                                           pdhg.get_output()),
                                       1.68590e-05,
                                       decimal=3)
Esempio n. 3
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 # Set regularisation parameter.
 alpha = 0.02
 
 # Create functions to be blocked with operators
 f1 = alpha * MixedL21Norm()
 f2 = 0.5 * L2NormSquared(b=blurredimage)
 
 # Create BlockOperator
 operator = BlockOperator(op1, op2, shape=(2,1) ) 
 
 # Create functions      
 f = BlockFunction(f1, f2) 
 g = ZeroFunction()
         
 # Compute operator Norm
 normK = operator.norm()
 
 # Primal & dual stepsizes
 sigma = 1
 tau = 1/(sigma*normK**2)
 
 # Setup and run the PDHG algorithm
 pdhg = PDHG(f=f,g=g,operator=operator, tau=tau, sigma=sigma)
 pdhg.max_iteration = 10000
 pdhg.update_objective_interval = 1
 pdhg.run(200,very_verbose=True)
 
 # Show results
 plt.figure(figsize=(20,5))
 plt.subplot(1,3,1)
 plt.imshow(data_gray.as_array(),vmin=0.0,vmax=1.0)
Esempio n. 4
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    def test_PDHG_vs_PDHG_explicit_axpby(self):
        data = dataexample.SIMPLE_PHANTOM_2D.get(size=(128, 128))
        if debug_print:
            print("test_PDHG_vs_PDHG_explicit_axpby here")
        ig = data.geometry
        ig.voxel_size_x = 0.1
        ig.voxel_size_y = 0.1

        detectors = ig.shape[0]
        angles = np.linspace(0, np.pi, 180)
        ag = AcquisitionGeometry('parallel',
                                 '2D',
                                 angles,
                                 detectors,
                                 pixel_size_h=0.1,
                                 angle_unit='radian')

        dev = 'cpu'

        Aop = AstraProjectorSimple(ig, ag, dev)

        sin = Aop.direct(data)
        # Create noisy data. Apply Gaussian noise
        noises = ['gaussian', 'poisson']
        noise = noises[1]
        if noise == 'poisson':
            np.random.seed(10)
            scale = 5
            eta = 0
            noisy_data = AcquisitionData(
                np.random.poisson(scale * (eta + sin.as_array())) / scale,
                geometry=ag)
        elif noise == 'gaussian':
            np.random.seed(10)
            n1 = np.random.normal(0, 0.1, size=ag.shape)
            noisy_data = AcquisitionData(n1 + sin.as_array(), geometry=ag)

        else:
            raise ValueError('Unsupported Noise ', noise)

        alpha = 0.5
        op1 = GradientOperator(ig)
        op2 = Aop
        # Create BlockOperator
        operator = BlockOperator(op1, op2, shape=(2, 1))
        f2 = KullbackLeibler(b=noisy_data)
        g = IndicatorBox(lower=0)
        normK = operator.norm()
        sigma = 1. / normK
        tau = 1. / normK

        f1 = alpha * MixedL21Norm()
        f = BlockFunction(f1, f2)
        # Setup and run the PDHG algorithm

        algos = []
        algos.append(
            PDHG(f=f,
                 g=g,
                 operator=operator,
                 tau=tau,
                 sigma=sigma,
                 max_iteration=1000,
                 update_objective_interval=200,
                 use_axpby=True))
        algos[0].run(1000, verbose=0)

        algos.append(
            PDHG(f=f,
                 g=g,
                 operator=operator,
                 tau=tau,
                 sigma=sigma,
                 max_iteration=1000,
                 update_objective_interval=200,
                 use_axpby=False))
        algos[1].run(1000, verbose=0)

        from cil.utilities.quality_measures import mae, mse, psnr
        qm = (mae(algos[0].get_output(), algos[1].get_output()),
              mse(algos[0].get_output(), algos[1].get_output()),
              psnr(algos[0].get_output(), algos[1].get_output()))
        if debug_print:
            print("Quality measures", qm)
        np.testing.assert_array_less(qm[0], 0.005)
        np.testing.assert_array_less(qm[1], 3e-05)
Esempio n. 5
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             update_objective_interval=2)
#%%
algo.update_objective_interval = 2
algo.run(10, verbose=1)

plotter2D(algo.solution, cmap='gist_earth')

# %%
from cil.optimisation.algorithms import PDHG
from cil.optimisation.functions import MixedL21Norm, BlockFunction, L2NormSquared, IndicatorBox
from cil.optimisation.operators import GradientOperator, BlockOperator

nabla = GradientOperator(ig_cs, backend='c')
F = BlockFunction(0.5 * L2NormSquared(b=ldata), alpha * MixedL21Norm())
BK = BlockOperator(K, nabla)
normK = BK.norm()

pdhg = PDHG(f=F,
            g=IndicatorBox(lower=0.),
            operator=BK,
            max_iteration=1000,
            update_objective_interval=100)
#%%
# pdhg.run(1000, verbose=2)
#%%
plotter2D(pdhg.solution, cmap='gist_earth')

# %%


class AcquisitionGeometrySubsetGenerator(object):