Example #1
0
def test_scale_space():
    num_levels = 3
    for test_class in [ScaleSpace, IsotropicScaleSpace]:
        for dim in [2, 3]:
            print(dim, test_class)
            if dim == 2:
                moving, static = get_synthetic_warped_circle(1)
            else:
                moving, static = get_synthetic_warped_circle(30)
            input_spacing = np.array([1.1, 1.2, 1.5])[:dim]
            grid2world = np.diag(tuple(input_spacing) + (1.0,))

            original = moving
            if test_class is ScaleSpace:
                ss = test_class(
                    original,
                    num_levels,
                    grid2world,
                    input_spacing)
            elif test_class is IsotropicScaleSpace:
                factors = [4, 2, 1]
                sigmas = [3.0, 1.0, 0.0]
                ss = test_class(
                    original,
                    factors,
                    sigmas,
                    grid2world,
                    input_spacing)
            for level in range(num_levels):
                # Verify sigmas and images are consistent
                sigmas = ss.get_sigmas(level)
                expected = sp.ndimage.filters.gaussian_filter(original, sigmas)
                expected = ((expected - expected.min()) /
                            (expected.max() - expected.min()))
                actual = ss.get_image(level)
                assert_array_almost_equal(actual, expected)

                # Verify scalings and spacings are consistent
                spacings = ss.get_spacing(level)
                scalings = ss.get_scaling(level)
                expected = ss.get_spacing(0) * scalings
                actual = ss.get_spacing(level)
                assert_array_almost_equal(actual, expected)

                # Verify affine and affine_inv are consistent
                affine = ss.get_affine(level)
                affine_inv = ss.get_affine_inv(level)
                expected = np.eye(1 + dim)
                actual = affine.dot(affine_inv)
                assert_array_almost_equal(actual, expected)

                # Verify affine consistent with spacings
                exp_dir, expected_sp = get_direction_and_spacings(affine, dim)
                actual_sp = spacings
                assert_array_almost_equal(actual_sp, expected_sp)
Example #2
0
def test_scale_space():
    num_levels = 3
    for test_class in [ScaleSpace, IsotropicScaleSpace]:
        for dim in [2, 3]:
            print(dim, test_class)
            if dim == 2:
                moving, static = get_synthetic_warped_circle(1)
            else:
                moving, static = get_synthetic_warped_circle(30)
            moving = cp.asarray(moving)
            static = cp.asarray(static)
            input_spacing = np.array([1.1, 1.2, 1.5])[:dim]
            grid2world = np.diag(tuple(input_spacing) + (1.0, ))

            original = moving
            if test_class is ScaleSpace:
                ss = test_class(original, num_levels, grid2world,
                                input_spacing)
            elif test_class is IsotropicScaleSpace:
                factors = [4, 2, 1]
                sigmas = [3.0, 1.0, 0.0]
                ss = test_class(original, factors, sigmas, grid2world,
                                input_spacing)
            for level in range(num_levels):
                # Verify sigmas and images are consistent
                sigmas = ss.get_sigmas(level)
                expected = ndi.gaussian_filter(original, sigmas)
                expected = (expected - expected.min()) / (expected.max() -
                                                          expected.min())
                actual = ss.get_image(level)
                cp.testing.assert_array_almost_equal(actual, expected)

                # Verify scalings and spacings are consistent
                spacings = ss.get_spacing(level)
                scalings = ss.get_scaling(level)
                expected = ss.get_spacing(0) * scalings
                actual = ss.get_spacing(level)
                cp.testing.assert_array_almost_equal(actual, expected)

                # Verify affine and affine_inv are consistent
                affine = ss.get_affine(level)
                affine_inv = ss.get_affine_inv(level)
                expected = np.eye(1 + dim)
                actual = affine.dot(affine_inv)
                cp.testing.assert_array_almost_equal(actual, expected)

                # Verify affine consistent with spacings
                exp_dir, expected_sp = get_direction_and_spacings(affine, dim)
                actual_sp = spacings
                cp.testing.assert_array_almost_equal(actual_sp, expected_sp)
Example #3
0
def test_get_direction_and_spacings():
    xrot = 0.5
    yrot = 0.75
    zrot = 1.0
    direction_gt = eulerangles.euler2mat(zrot, yrot, xrot)
    spacings_gt = np.array([1.1, 1.2, 1.3])
    scaling_gt = np.diag(spacings_gt)
    translation_gt = np.array([1,2,3])

    affine = np.eye(4)
    affine[:3, :3] = direction_gt.dot(scaling_gt)
    affine[:3, 3] = translation_gt

    direction, spacings = imwarp.get_direction_and_spacings(affine, 3)
    assert_array_almost_equal(direction, direction_gt)
    assert_array_almost_equal(spacings, spacings_gt)
Example #4
0
def changeFoV(image_nib, new_FOV, com=False):

    if isinstance(new_FOV, list):
        try:
            new_FOV = np.array(new_FOV)
        except:
            raise IOError("list of fields of view")

    image_shape = np.array(image_nib.shape)
    direction, spacing = get_direction_and_spacings(image_nib.affine,
                                                    image_nib.ndim)
    old_fov = image_shape * spacing

    print("Input Image has:"
          "FOVs: {} "
          "Our New FOVs: {}".format(old_fov, new_FOV))

    doit = False
    for f, fov in enumerate(old_fov):
        if (abs(fov - new_FOV[f]) >= 2 * spacing[f]):
            doit = True
        else:
            doit = False
            break

    if not doit:
        return image_nib.get_data(), image_nib.affine

    arr = image_nib.get_data()
    # Assume B_0 image is always the first vol
    if image_nib.ndim > 3:
        b0_image = arr[:, :, :, 0]
    else:
        b0_image = arr

    nVols = image_shape[-1]

    if com:
        new_image, new_affine = crop4D(image_nib, new_FOV, b0_image)
    else:
        new_image, new_affine = changeFOVimage(image_nib, new_FOV)

    return new_image, new_affine
Example #5
0
static = ((static.astype(np.float64) - static.min()) /
          (static.max() - static.min()))
moving = ((moving.astype(np.float64) - moving.min()) /
          (moving.max() - moving.min()))

static = np.array(static).astype(np.float64)
moving = np.array(moving).astype(np.float64)

import numpy.linalg as npl
moving_world2grid = npl.inv(moving_grid2world)

from dipy.align.imwarp import get_direction_and_spacings
dim = len(static.shape)
moving_direction, moving_spacing = \
    get_direction_and_spacings(moving_grid2world, dim)

from dipy.align.vector_fields import _gradient_3d
out_shape = static.shape
ftype = moving.dtype.type
out = np.empty(tuple(out_shape) + (dim, ), dtype=ftype)
inside = np.empty(tuple(out_shape), dtype=np.int32)
_gradient_3d(moving, moving_world2grid, moving_spacing, static_grid2world, out,
             inside)

mgrad = np.asarray(out)

from dipy.align.imaffine import AffineMap
dim = len(static.shape)
starting_affine = np.eye(dim + 1)
affine_map = AffineMap(starting_affine, static.shape, static_grid2world,
Example #6
0
def changeFOVimage(image, new_FOV):
    arr = image.get_data()
    affine = image.affine
    n = 3
    if isinstance(new_FOV, list):
        try:
            new_FOV = np.array(new_FOV)
        except:
            raise IOError("list of fields of view")

    direction, spacing = get_direction_and_spacings(affine, arr.ndim)
    print(direction, spacing)
    arr_size = arr.size
    arr_shape = np.array(arr.shape)
    old_fov = np.abs(spacing.dot(direction) * arr_shape)
    origin = affine[:3, 3]

    print("Input Image has:"
          "FOVs: {} "
          "Our New FOVs: {}".format(old_fov, new_FOV))

    doit = False
    for f, fov in enumerate(old_fov):
        if (abs(fov - new_FOV[f]) >= 2 * spacing[f]):
            doit = True
        else:
            doit = False
            break

    if not doit:
        print("Can't Change FOV - Return original image")
        return image, affine

    total_add_3D, total_remove_3D = np.zeros(n).astype(int), np.zeros(
        n).astype(int)

    new_origin_index = np.zeros(n).astype(int)
    new_size = np.zeros(n).astype(int)
    start_from = np.zeros(n).astype(int)
    start_from_new, from_old_size = np.zeros(n).astype(int), np.zeros(
        n).astype(int)

    for d, fov in enumerate(old_fov[:n]):
        print(d)
        if new_FOV[d] > fov:
            # print("Dimension {} process add".format(d))
            total_add_3D[d] = (np.ceil((new_FOV[d] - fov) / spacing[d]))
            if ((total_add_3D[d] % 2) == 1):
                total_add_3D[d] += 1
            new_origin_index[d] = -(total_add_3D[d] / 2)
            new_size[d] = (arr_shape[d] + total_add_3D[d])
            start_from[d] = 0
            start_from_new[d] = total_add_3D[d] / 2
            from_old_size[d] = arr_shape[d]

        else:
            # print("Dimension {} process remove".format(d))
            total_remove_3D[d] = (np.floor((fov - new_FOV[d]) / spacing[d]))
            if ((total_remove_3D[d] % 2) == 1):
                total_remove_3D[d] -= 1
            new_origin_index[d] = (total_remove_3D[d] / 2)
            new_size[d] = (arr_shape[d] - total_remove_3D[d])
            start_from[d] = total_remove_3D[d] / 2
            start_from_new[d] = 0
            from_old_size[d] = arr_shape[d] - total_remove_3D[d]

    # new_origin = origin + spacing * new_origin_index
    # new_origin = _transformIndextoPhysicalPoint(new_origin_index, spacing, direction, origin)
    new_origin = _transformIndextoPhysicalPoint_with_affine(
        affine, new_origin_index)
    new_affine = affine.copy()
    new_affine[0:3, 3] = new_origin
    if arr.ndim > 3:

        new_image = arr[start_from[0]:start_from[0] + from_old_size[0],
                        start_from[1]:start_from[1] + from_old_size[1],
                        start_from[2]:start_from[2] + from_old_size[2], :]
    else:
        new_image = arr[start_from[0]:start_from[0] + from_old_size[0],
                        start_from[1]:start_from[1] + from_old_size[1],
                        start_from[2]:start_from[2] + from_old_size[2]]
    return new_image, new_affine
Example #7
0
def crop4D(image, new_FOV, b0_image):
    arr = image.get_data()
    affine = image.affine
    n = arr.ndim

    if isinstance(new_FOV, list):
        try:
            new_FOV = np.array(new_FOV)
        except:
            raise IOError("list of fields of view")

    direction, spacing = get_direction_and_spacings(affine, arr.ndim)
    # print(direction, spacing)
    arr_size = arr.size
    arr_shape = np.array(arr.shape)
    old_fov = np.abs(spacing.dot(direction) * arr_shape)
    origin = affine[:3, 3]
    print("Input Image has:"
          "FOVs: {} "
          "Our New FOVs: {}".format(old_fov, new_FOV))

    doit = False
    for f, fov in enumerate(old_fov):
        if (abs(fov - new_FOV[f]) >= 2 * spacing[f]):
            doit = True

    if not doit:
        return image.get_data(), image.affine
    # get center of mass index and point
    center_index = _get_centerOfGravityPt(b0_image)
    center_pt = _transformIndextoPhysicalPoint(center_index, spacing,
                                               direction, origin)

    scl = direction[:3, :3] * np.diag(spacing)

    new_size = np.ceil(new_FOV / spacing)
    new_center_index = (new_size - 1) // 2
    new_origin = np.zeros(3)

    # Find new_origin
    for r in range(3):
        sm = np.sum(scl[r, :] * new_center_index)
        new_origin[r] = center_pt[r] - sm

    spc4 = np.zeros(4)
    spc4[:-1] = spacing
    spc4[-1] = 1

    dir4 = np.eye(4, 4)
    dir4[:3, :3] = direction[:3, :3]

    new_origin4 = np.zeros(4)
    new_origin4[:3] = new_origin

    destination_index = np.zeros(3).astype(int)
    source_start = np.zeros(3).astype(int)
    source_size = np.zeros(3).astype(int)

    for d in range(3):
        if (new_center_index[d] < center_index[d]):
            destination_index[d] = 0
            source_start[d] = center_index[d] - new_center_index[d]

            if (source_start[d] + new_size[d] > arr.shape[d]):
                source_size[d] = arr.shape[d] - source_start[d] - 1

            else:
                source_size[d] = new_size[d]

        else:
            destination_index[d] = new_center_index[d] - center_index[d]
            source_start[d] = 0

            if (arr.shape[d] > new_size[d]):
                source_size[d] = new_size[d]
            else:
                source_size[d] = arr.shape[d]
    if arr.ndim > 3:
        new_image = arr[source_start[0]:source_start[0] + source_size[0],
                        source_start[1]:source_start[1] + source_size[1],
                        source_start[2]:source_start[2] + source_size[2], :]

    else:
        new_image = arr[source_start[0]:source_start[0] + source_size[0],
                        source_start[1]:source_start[1] + source_size[1],
                        source_start[2]:source_start[2] + source_size[2]]
    new_affine = affine
    new_affine[0:3, 3] = new_origin
    return new_image, new_affine