def __init__(self, geometry, vol_space, proj_space):
"""Initialize a new instance.
Parameters
----------
geometry : `Geometry`
Geometry defining the tomographic setup.
vol_space : `DiscretizedSpace`
Reconstruction space, the space of the images to be forward
projected.
proj_space : `DiscretizedSpace`
Projection space, the space of the result.
"""
if not isinstance(geometry, Geometry):
raise TypeError(
'`geometry` must be a `Geometry` instance, got {!r}'
''.format(geometry))
if not isinstance(vol_space, DiscretizedSpace):
raise TypeError(
'`vol_space` must be a `DiscretizedSpace` instance, got {!r}'
''.format(vol_space))
if not isinstance(proj_space, DiscretizedSpace):
raise TypeError(
'`proj_space` must be a `DiscretizedSpace` instance, got {!r}'
''.format(proj_space))
# Print a warning if the detector midpoint normal vector at any
# angle is perpendicular to the geometry axis in parallel 3d
# single-axis geometry -- this is broken in some ASTRA versions
if (isinstance(geometry, Parallel3dAxisGeometry)
and not astra_supports('par3d_det_mid_pt_perp_to_axis')):
req_ver = astra_versions_supporting(
'par3d_det_mid_pt_perp_to_axis')
axis = geometry.axis
mid_pt = geometry.det_params.mid_pt
for i, angle in enumerate(geometry.angles):
if abs(np.dot(axis, geometry.det_to_src(angle,
mid_pt))) < 1e-4:
warnings.warn(
'angle {}: detector midpoint normal {} is '
'perpendicular to the geometry axis {} in '
'`Parallel3dAxisGeometry`; this is broken in '
'ASTRA {}, please upgrade to ASTRA {}'
''.format(i, geometry.det_to_src(angle, mid_pt), axis,
ASTRA_VERSION, req_ver), RuntimeWarning)
break
self.geometry = geometry
self._vol_space = vol_space
self._proj_space = proj_space
self.create_ids()
# ASTRA projectors are not thread-safe, thus we need to lock manually
self._mutex = Lock()
def test_vol_geom_3d():
"""Check correctness of ASTRA 3D volume geometies."""
x_pts = 10
y_pts = 20
z_pts = 30
# Isotropic voxel case
discr_dom = _discrete_domain(3, 'nearest')
# x = columns, y = rows, z = slices
correct_dict = {
'GridColCount': z_pts,
'GridRowCount': y_pts,
'GridSliceCount': x_pts,
'option': {
'WindowMinX': -3.0, # z_min
'WindowMaxX': 3.0, # z_max
'WindowMinY': -2.0, # y_min
'WindowMaxY': 2.0, # y_amx
'WindowMinZ': -1.0, # x_min
'WindowMaxZ': 1.0
}
} # x_amx
vol_geom = odl.tomo.astra_volume_geometry(discr_dom)
assert vol_geom == correct_dict
discr_dom = _discrete_domain_anisotropic(3, 'nearest')
# x = columns, y = rows, z = slices
correct_dict = {
'GridColCount': z_pts,
'GridRowCount': y_pts,
'GridSliceCount': x_pts,
'option': {
'WindowMinX': -1.0, # z_min
'WindowMaxX': 1.0, # z_max
'WindowMinY': -1.0, # y_min
'WindowMaxY': 1.0, # y_amx
'WindowMinZ': -1.0, # x_min
'WindowMaxZ': 1.0
}
} # x_amx
if astra_supports('anisotropic_voxels_3d'):
vol_geom = odl.tomo.astra_volume_geometry(discr_dom)
assert vol_geom == correct_dict
else:
with pytest.raises(NotImplementedError):
odl.tomo.astra_volume_geometry(discr_dom)
def test_vol_geom_2d():
"""Check correctness of ASTRA 2D volume geometries."""
x_pts = 10 # x_pts = Rows
y_pts = 20 # y_pts = Columns
# Isotropic voxel case
discr_dom = _discrete_domain(2, 'nearest')
correct_dict = {
'GridColCount': y_pts,
'GridRowCount': x_pts,
'option': {
'WindowMinX': -2.0, # y_min
'WindowMaxX': 2.0, # y_max
'WindowMinY': -1.0, # x_min
'WindowMaxY': 1.0
}
} # x_amx
vol_geom = odl.tomo.astra_volume_geometry(discr_dom)
assert vol_geom == correct_dict
# Anisotropic voxel case
discr_dom = _discrete_domain_anisotropic(2, 'nearest')
correct_dict = {
'GridColCount': y_pts,
'GridRowCount': x_pts,
'option': {
'WindowMinX': -1.0, # y_min
'WindowMaxX': 1.0, # y_max
'WindowMinY': -1.0, # x_min
'WindowMaxY': 1.0
}
} # x_amx
if astra_supports('anisotropic_voxels_2d'):
vol_geom = odl.tomo.astra_volume_geometry(discr_dom)
assert vol_geom == correct_dict
else:
with pytest.raises(NotImplementedError):
odl.tomo.astra_volume_geometry(discr_dom)
