Exemplo n.º 1
0
def geometry(request):
    geom = request.param
    m = 100
    n_angles = 100

    if geom == 'par2d':
        apart = odl.uniform_partition(0, np.pi, n_angles)
        dpart = odl.uniform_partition(-30, 30, m)
        return tomo.Parallel2dGeometry(apart, dpart)
    elif geom == 'par3d':
        apart = odl.uniform_partition(0, np.pi, n_angles)
        dpart = odl.uniform_partition([-30, -30], [30, 30], (m, m))
        return tomo.Parallel3dAxisGeometry(apart, dpart)
    elif geom == 'cone2d':
        apart = odl.uniform_partition(0, 2 * np.pi, n_angles)
        dpart = odl.uniform_partition(-30, 30, m)
        return tomo.FanFlatGeometry(apart,
                                    dpart,
                                    src_radius=200,
                                    det_radius=100)
    elif geom == 'cone3d':
        apart = odl.uniform_partition(0, 2 * np.pi, n_angles)
        dpart = odl.uniform_partition([-60, -60], [60, 60], (m, m))
        return tomo.CircularConeFlatGeometry(apart,
                                             dpart,
                                             src_radius=200,
                                             det_radius=100)
    elif geom == 'helical':
        apart = odl.uniform_partition(0, 8 * 2 * np.pi, n_angles)
        dpart = odl.uniform_partition([-30, -3], [30, 3], (m, m))
        return tomo.HelicalConeFlatGeometry(apart,
                                            dpart,
                                            pitch=5.0,
                                            src_radius=200,
                                            det_radius=100)
    else:
        raise ValueError('geom not valid')
Exemplo n.º 2
0
def projector(request, dtype):

    n_angles = 200

    geom, impl, angle = request.param.split()

    if angle == 'uniform':
        apart = odl.uniform_partition(0, 2 * np.pi, n_angles)
    elif angle == 'random':
        # Linearly spaced with random noise
        min_pt = 2 * (2.0 * np.pi) / n_angles
        max_pt = (2.0 * np.pi) - 2 * (2.0 * np.pi) / n_angles
        points = np.linspace(min_pt, max_pt, n_angles)
        points += np.random.rand(n_angles) * (max_pt - min_pt) / (5 * n_angles)
        apart = odl.nonuniform_partition(points)
    elif angle == 'nonuniform':
        # Angles spaced quadratically
        min_pt = 2 * (2.0 * np.pi) / n_angles
        max_pt = (2.0 * np.pi) - 2 * (2.0 * np.pi) / n_angles
        points = np.linspace(min_pt ** 0.5, max_pt ** 0.5, n_angles) ** 2
        apart = odl.nonuniform_partition(points)
    else:
        raise ValueError('angle not valid')

    if geom == 'par2d':
        # Discrete reconstruction space
        discr_reco_space = odl.uniform_discr([-20, -20], [20, 20],
                                             [100, 100], dtype=dtype)

        # Geometry
        dpart = odl.uniform_partition(-30, 30, 200)
        geom = tomo.Parallel2dGeometry(apart, dpart)

        # Ray transform
        return tomo.RayTransform(discr_reco_space, geom,
                                 impl=impl)

    elif geom == 'par3d':
        # Discrete reconstruction space
        discr_reco_space = odl.uniform_discr([-20, -20, -20], [20, 20, 20],
                                             [100, 100, 100], dtype=dtype)

        # Geometry
        dpart = odl.uniform_partition([-30, -30], [30, 30], [200, 200])
        geom = tomo.Parallel3dAxisGeometry(apart, dpart, axis=[1, 0, 0])

        # Ray transform
        return tomo.RayTransform(discr_reco_space, geom,
                                 impl=impl)

    elif geom == 'cone2d':
        # Discrete reconstruction space
        discr_reco_space = odl.uniform_discr([-20, -20], [20, 20],
                                             [100, 100], dtype=dtype)

        # Geometry
        dpart = odl.uniform_partition(-30, 30, 200)
        geom = tomo.FanFlatGeometry(apart, dpart,
                                    src_radius=200, det_radius=100)

        # Ray transform
        return tomo.RayTransform(discr_reco_space, geom,
                                 impl=impl)

    elif geom == 'cone3d':
        # Discrete reconstruction space
        discr_reco_space = odl.uniform_discr([-20, -20, -20], [20, 20, 20],
                                             [100, 100, 100], dtype=dtype)

        # Geometry
        dpart = odl.uniform_partition([-30, -30], [30, 30], [200, 200])
        geom = tomo.CircularConeFlatGeometry(
            apart, dpart, src_radius=200, det_radius=100, axis=[1, 0, 0])

        # Ray transform
        return tomo.RayTransform(discr_reco_space, geom,
                                 impl=impl)

    elif geom == 'helical':
        # Discrete reconstruction space
        discr_reco_space = odl.uniform_discr([-20, -20, 0], [20, 20, 40],
                                             [100, 100, 100], dtype=dtype)

        # Geometry
        # TODO: angles
        n_angle = 700
        apart = odl.uniform_partition(0, 8 * 2 * np.pi, n_angle)
        dpart = odl.uniform_partition([-30, -3], [30, 3], [200, 20])
        geom = tomo.HelicalConeFlatGeometry(apart, dpart, pitch=5.0,
                                            src_radius=200, det_radius=100)

        # Ray transform
        return tomo.RayTransform(discr_reco_space, geom,
                                 impl=impl)
    else:
        raise ValueError('param not valid')