Ejemplo n.º 1
0
    def setUpClass(cls):
        # Point self to cls so we can use it like in a normal method
        self = cls

        # Load in test data
        self.path = ('mr_utils/test_data/tests/cs/convex/' 'temporal_gd_tv')
        self.Coil, self.mask = load_test_data(self.path, ['Coil6', 'mask'])

        # For some reason they are the wrong dimensions coming out
        # of MATLAB, probably because they are old format
        self.Coil = self.Coil.T
        self.mask = self.mask.T

        # Set the recon parameters
        self.weight_fidelity = 1
        self.weight_temporal = .01
        self.beta_sqrd = 0.0000001
        self.niter = 200

        # Get an encoding model
        self.uft = UFT(self.mask, axes=(0, 1))

        # Compute reduced kspace
        self.reduced_kspace = self.Coil * self.mask

        # Compute prior
        self.prior = generate_prior(self.Coil * self.mask, self.uft.inverse_s)

        # Compute monotonic sort order
        (self.sort_order_real,
         self.sort_order_imag) = sort_real_imag_parts(self.prior, axis=-1)

        # Compute measured image domain
        self.measuredImgDomain = self.uft.inverse_s(self.reduced_kspace)

        # Get reduced data, whatever that is
        self.reduced_data = np.abs(self.measuredImgDomain)

        # Get initial estimates
        self.img_est = self.measuredImgDomain.copy()
        self.W_img_est = self.measuredImgDomain.copy()

        # Construct R and C (rows and columns, I assume)
        rows, cols, pages = self.img_est.shape[:]
        self.R = np.tile(np.arange(rows), (cols, pages, 1)).transpose(
            (2, 0, 1))
        self.C = np.tile(np.arange(cols), (rows, pages, 1)).transpose(
            (0, 2, 1))

        # From R and C get the indices we'll actually use
        self.nIdx_real = self.R + self.C * rows + (
            self.sort_order_real) * rows * cols
        self.nIdx_imag = self.R + self.C * rows + (
            self.sort_order_imag) * rows * cols
Ejemplo n.º 2
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class TestAMP(unittest.TestCase):
    '''Make sure we line up with Stanford results.'''
    def setUp(self):
        data = load_test_data('mr_utils/test_data/tests/cs/thresholding/amp',
                              ['cdf97', 'mask', 'x0', 'y'])
        self.cdf97, self.mask, self.x0, self.y = data[:]  #pylint: disable=W0632
        self.uft = UFT(self.mask)
        self.level = 5

    def test_uft(self):
        '''Test undersampled fourier encoding.'''

        y0 = self.uft.forward_ortho(self.x0)
        self.assertTrue(np.allclose(self.y, y0))

    @unittest.skip('Currently do not know how to match cdf97 using pywavelets')
    def test_wavelet_decomposition(self):
        '''Make sure we decompose using the same wavelet transformation.'''

        wavelet_transform, locations = cdf97_2d_forward(self.x0, self.level)

        # # Check 'em out
        # view(np.stack((np.log(np.abs(self.cdf97)),
        #                np.log(np.abs(wavelet_transform)))))
        # view(np.stack((self.cdf97 - wavelet_transform)), log=True)
        #
        # # Make sure we can go back
        inverse = cdf97_2d_inverse(wavelet_transform, locations)
        self.assertTrue(np.allclose(self.x0, inverse))
        # view(self.x0 - inverse)
        # view(cdf97_2d_inverse(wavelet_transform, locations))

        # Currently failing...
        self.assertTrue(np.allclose(wavelet_transform, self.cdf97))
Ejemplo n.º 3
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    # Undersampling pattern
    samp0 = np.zeros((sx, sy, st))
    desc = 'Making sampling mask'
    num_spokes = 16
    offsets = np.random.randint(0, high=st, size=st)
    for ii in trange(st, leave=False, desc=desc):
        samp0[..., ii] = radial(
            (sx, sy), num_spokes, offset=offsets[ii],
            extend=True, skinny=False)
    # view(samp0)

    # Set up the recon
    x = imspace_true.copy()
    ax = (0, 1)
    uft = UFT(samp0, axes=ax, scale=True)
    forward = uft.forward_ortho
    inverse = uft.inverse_ortho
    y = forward(x)
    # view(y, log=True)
    imspace_u = inverse(y)

    # from mr_utils.cs import SpatioTemporalTVSB
    # recon, err = SpatioTemporalTVSB(
    #     samp0, y, betaxy=1/4, betat=1, mu=1, lam=1, gamma=1/2,
    #     nInner=1, niter=3, x=x)
    # view(recon)


    w = 50
    recon_l1 = ptv.tvgen(
from mr_utils import view
from mr_utils.cs import proximal_GD
from mr_utils.cs.models import UFT
from mr_utils.utils.wavelet import cdf97_2d_forward, cdf97_2d_inverse
from mr_utils.utils.orderings import bulk_up, whittle_down, colwise, rowwise
from mr_utils.utils.sort2d import sort2d

if __name__ == '__main__':

    # We need a mask
    mask = load_test_data('mr_utils/test_data/tests/recon/reordering',
                          ['mask'])[0]
    mask = np.fft.fftshift(mask)

    # Get the encoding model
    uft = UFT(mask)

    # Load in the test data
    kspace = load_test_data('mr_utils/test_data/tests/recon/reordering',
                            ['coil1'])[0]
    kspace = np.fft.fftshift(kspace)
    imspace = uft.inverse(kspace)

    # Undersample data to get prior
    kspace_u = kspace * mask
    imspace_u = uft.inverse(kspace_u)

    # Sparsifying transforms
    level = 3
    wvlt, locations = cdf97_2d_forward(imspace, level)
    sparsify = lambda x: cdf97_2d_forward(x, level)[0]
Ejemplo n.º 5
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class TestTemporalGDTV(unittest.TestCase):
    '''Make sure output of function matches MATLAB output.'''
    @classmethod
    def setUpClass(cls):
        # Point self to cls so we can use it like in a normal method
        self = cls

        # Load in test data
        self.path = ('mr_utils/test_data/tests/cs/convex/' 'temporal_gd_tv')
        self.Coil, self.mask = load_test_data(self.path, ['Coil6', 'mask'])

        # For some reason they are the wrong dimensions coming out
        # of MATLAB, probably because they are old format
        self.Coil = self.Coil.T
        self.mask = self.mask.T

        # Set the recon parameters
        self.weight_fidelity = 1
        self.weight_temporal = .01
        self.beta_sqrd = 0.0000001
        self.niter = 200

        # Get an encoding model
        self.uft = UFT(self.mask, axes=(0, 1))

        # Compute reduced kspace
        self.reduced_kspace = self.Coil * self.mask

        # Compute prior
        self.prior = generate_prior(self.Coil * self.mask, self.uft.inverse_s)

        # Compute monotonic sort order
        (self.sort_order_real,
         self.sort_order_imag) = sort_real_imag_parts(self.prior, axis=-1)

        # Compute measured image domain
        self.measuredImgDomain = self.uft.inverse_s(self.reduced_kspace)

        # Get reduced data, whatever that is
        self.reduced_data = np.abs(self.measuredImgDomain)

        # Get initial estimates
        self.img_est = self.measuredImgDomain.copy()
        self.W_img_est = self.measuredImgDomain.copy()

        # Construct R and C (rows and columns, I assume)
        rows, cols, pages = self.img_est.shape[:]
        self.R = np.tile(np.arange(rows), (cols, pages, 1)).transpose(
            (2, 0, 1))
        self.C = np.tile(np.arange(cols), (rows, pages, 1)).transpose(
            (0, 2, 1))

        # From R and C get the indices we'll actually use
        self.nIdx_real = self.R + self.C * rows + (
            self.sort_order_real) * rows * cols
        self.nIdx_imag = self.R + self.C * rows + (
            self.sort_order_imag) * rows * cols

    def test_reduced_kspace(self):
        '''Verify reduced_kspace variable is the same as MATLAB'''

        reduced_kspace_true = load_test_data(self.path, ['reduced_kspace'])
        self.assertTrue(np.allclose(self.reduced_kspace, reduced_kspace_true))

    def test_generate_prior(self):
        '''Verify prior variable is the same as MATLAB'''

        prior_true = load_test_data(
            self.path,
            ['prior'],
        )
        self.assertTrue(np.allclose(self.prior, prior_true))

    def test_monotonic_sort_real_imag_parts(self):
        '''Verify sort orders are the same as MATLAB'''

        real_true, imag_true = load_test_data(
            self.path, ['sort_order_real', 'sort_order_imag'])
        # 0-based indexing
        real_true -= 1
        imag_true -= 1
        self.assertTrue(np.alltrue(self.sort_order_real == real_true))
        self.assertTrue(np.alltrue(self.sort_order_imag == imag_true))

    def test_measuredImgDomain(self):
        '''Verify measuredImgDomain variable same as MATLAB'''

        mid = load_test_data(self.path, ['measuredImgDomain'])
        self.assertTrue(np.allclose(self.measuredImgDomain, mid))

    def test_reduced_data(self):
        '''Verify reduced_data variable same as MATLAB'''

        reduced_data = load_test_data(self.path, ['reduced_data'])
        self.assertTrue(np.allclose(self.reduced_data, reduced_data))

    def test_R_and_C(self):
        '''Verify R, C variables are the same as MATLAB'''

        R, C = load_test_data(self.path, ['R', 'C'])
        self.assertTrue(np.allclose(self.R, R - 1))
        self.assertTrue(np.allclose(self.C, C - 1))

    def test_nIdx_real_and_imag(self):
        '''Verify nIdx_real/imag variables are the same as MATLAB'''

        real, imag = load_test_data(self.path, ['nIdx_real', 'nIdx_imag'])

        # print(np.unravel_index(self.nIdx_real, self.prior.shape))

        self.assertTrue(np.allclose(self.nIdx_real, real - 1))
        self.assertTrue(np.allclose(self.nIdx_imag, imag - 1))

    def test_recon(self):
        '''See if the full recon matches the MATLAB output'''

        recon = GD_temporal_TV(self.prior,
                               self.reduced_kspace,
                               self.mask,
                               self.weight_fidelity,
                               self.weight_temporal,
                               self.uft.forward_s,
                               self.uft.inverse_s,
                               x=self.Coil)
        view(recon)
Ejemplo n.º 6
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from mr_utils import view
from mr_utils.cs import GD_TV
from mr_utils.cs.models import UFT
from mr_utils.test_data.phantom import binary_smiley
from mr_utils.sim.traj import cartesian_pe

if __name__ == '__main__':

    # Same binary smiley face example
    do_reordering = True
    N = 1000
    x = binary_smiley(N)
    k = np.sum(np.abs(np.diff(x)) > 0)
    np.random.seed(5)
    samp = cartesian_pe(x.shape, undersample=.2, reflines=5)
    uft = UFT(samp)

    # Make the complex measurement in kspace
    # Note this is different than uft.forward, as fftshift must be performed
    y = uft.forward_ortho(x)

    # Solve inverse problem using gradient descent with TV sparsity constraint
    x_hat = GD_TV(y,
                  forward_fun=uft.forward_ortho,
                  inverse_fun=uft.inverse_ortho,
                  alpha=.5,
                  lam=.022,
                  do_reordering=do_reordering,
                  x=x,
                  ignore_residual=True,
                  disp=True,
Ejemplo n.º 7
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    plt.hist(im.imag.flatten(), density=True)
    plt.title('Distribution of Imag')
    plt.xlabel('Variance: %g' % laplace_sample_var(im.imag.flatten()))

    plt.subplot(1, 3, 3)
    plt.hist(np.abs(im.flatten()), density=True)
    plt.title('Distribution of Mag')
    plt.xlabel('Variance: %g' % exp_sample_var(np.abs(im).flatten()))

    plt.show()

    # Radial sampling pattern for retrospective undersampling
    num_spokes = 16
    samp = radial(im.shape, num_spokes, skinny=True, extend=True)
    samp_percent = np.sum(samp.flatten()) / samp.size * 100
    uft = UFT(samp)
    kspace_u = np.fft.fft2(im) * samp
    imspace_u = np.fft.ifft2(kspace_u)
    # view(samp)
    # view(imspace_u)
    # view(kspace_u)

    # Use wavelet transform
    lvl = 3
    _coeffs, locs = cdf97_2d_forward(im, lvl)
    sparsify = lambda x0: cdf97_2d_forward(x0, lvl)[0]
    unsparsify = lambda x0: cdf97_2d_inverse(x0, locs)
    assert np.allclose(unsparsify(sparsify(im)), im)

    # Recon params
    ignore_mse = False
Ejemplo n.º 8
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from mr_utils.test_data.phantom import binary_smiley
from mr_utils.sim.traj import radial
from mr_utils.cs.models import UFT
from mr_utils.cs import proximal_GD
from mr_utils.utils.wavelet import cdf97_2d_forward, cdf97_2d_inverse
from mr_utils.utils.sort2d import sort2d

if __name__ == '__main__':

    # Phantom
    N = 2**9
    x = binary_smiley(N)

    # Sampling mask and encoding model
    mask = radial(x.shape, 16, extend=True)
    uft = UFT(mask)

    # Sample
    y = uft.forward_ortho(x)

    # Decide how we'll be selective in our updates
    percent_to_keep = .04
    num_to_keep = int(percent_to_keep * y.size)

    def select_n(x_hat, update):
        '''Return indices of n largest updates each iteration.'''
        return np.unravel_index(
            np.argpartition(np.abs(x_hat - update).flatten(),
                            -num_to_keep)[-num_to_keep:], x_hat.shape)

    idx = np.arange(y.size).reshape(y.shape)
Ejemplo n.º 9
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from mr_utils.utils.wavelet import cdf97_2d_forward, cdf97_2d_inverse
from mr_utils.sim.traj import radial
from mr_utils.cs.models import UFT
from mr_utils.cs import proximal_GD
from mr_utils import view

if __name__ == '__main__':

    # Get a phantom
    N = 64
    x = binary_smiley(N)

    # Do some sampling
    num_spokes = 12
    mask = radial(x.shape, num_spokes)
    uft = UFT(mask)
    y = uft.forward_ortho(x)

    # Sparsifying transforms
    level = 3
    wvlt, locations = cdf97_2d_forward(x, level)
    sparsify = lambda x0: cdf97_2d_forward(x0, level)[0]
    unsparsify = lambda x0: cdf97_2d_inverse(x0, locations)

    # Do the recon
    alpha = .15
    disp = True
    ignore = False
    maxiter = 200
    x_c = proximal_GD(y,
                      forward_fun=uft.forward_ortho,
Ejemplo n.º 10
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 def setUp(self):
     data = load_test_data('mr_utils/test_data/tests/cs/thresholding/amp',
                           ['cdf97', 'mask', 'x0', 'y'])
     self.cdf97, self.mask, self.x0, self.y = data[:]  #pylint: disable=W0632
     self.uft = UFT(self.mask)
     self.level = 5
Ejemplo n.º 11
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    num_spokes = 16
    run = ['monosort', 'lagrangian']  # none is always run to get prior

    # Need a reasonable numerical phantom
    x = np.rot90(modified_shepp_logan((N, N, N))[:, :, int(N / 2)])
    # view(x)

    # Sparsifying transform
    level = 3
    wvlt, locations = cdf97_2d_forward(x, level)
    sparsify = lambda x: cdf97_2d_forward(x, level)[0]
    unsparsify = lambda x: cdf97_2d_inverse(x, locations)

    # Do radial golden-angle sampling
    mask = radial(x.shape, num_spokes, skinny=True, extend=False)
    uft = UFT(mask)
    kspace_u = uft.forward_ortho(x)
    view(kspace_u, fft=True)

    # # We need to find the best alpha for the no ordering recon
    # pGD = partial(
    #     proximal_GD, y=kspace_u, forward_fun=uft.forward_ortho,
    #     inverse_fun=uft.inverse_ortho, sparsify=sparsify,
    #     unsparsify=unsparsify, mode='soft', thresh_sep=True,
    #     selective=None, x=x, ignore_residual=False, disp=False,
    #     maxiter=500)
    # obj = lambda alpha0: compare_mse(
    #     np.abs(x), np.abs(pGD(alpha=alpha0)))
    # alpha0 = 0.05
    # res = minimize(obj, alpha0)
    # print(res)
Ejemplo n.º 12
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import matplotlib.pyplot as plt
from skimage.measure import compare_mse
from mr_utils.cs import IHT_TV
from mr_utils.cs.models import UFT
from mr_utils.test_data.phantom import binary_smiley
from mr_utils.sim.traj import cartesian_pe

if __name__ == '__main__':

    do_reordering = True
    N = 1000
    x = binary_smiley(N)
    k = np.sum(np.abs(np.diff(x)) > 0)
    np.random.seed(5)
    samp = cartesian_pe(x.shape, undersample=.01, reflines=5)
    uft = UFT(samp)  # acquisiton model

    # Show sampling pattern
    plt.imshow(samp, cmap='gray')
    plt.title('Sampling Pattern')
    plt.show()

    # Simulate acquisiton
    kspace_u = uft.forward_ortho(x)
    imspace_u = uft.inverse_ortho(kspace_u)

    # Look at the aliased acquired signal
    plt.imshow(np.abs(imspace_u), cmap='gray')
    plt.title('Acquired')
    plt.show()