def derenzo_sources(space):
"""Create the PET/SPECT Derenzo sources phantom.
The Derenzo phantom contains a series of circles of decreasing size.
In 3d the phantom is simply the 2d phantom extended in the z direction as
cylinders.
"""
if space.ndim == 2:
return ellipsoid_phantom(space, _derenzo_sources_2d())
if space.ndim == 3:
return ellipsoid_phantom(
space, cylinders_from_ellipses(_derenzo_sources_2d()))
else:
raise ValueError('dimension not 2, no phantom available')
def derenzo_sources(space):
"""Create the PET/SPECT Derenzo sources phantom.
The Derenzo phantom contains a series of circles of decreasing size.
In 3d the phantom is simply the 2d phantom extended in the z direction as
cylinders.
"""
if space.ndim == 2:
return ellipsoid_phantom(space, _derenzo_sources_2d())
if space.ndim == 3:
return ellipsoid_phantom(
space, cylinders_from_ellipses(_derenzo_sources_2d()))
else:
raise ValueError('dimension not 2, no phantom available')
def shepp_logan(space, modified=False):
"""Standard `Shepp-Logan phantom`_ in 2 or 3 dimensions.
Parameters
----------
space : `DiscreteLp`
Space in which the phantom is created, must be 2- or 3-dimensional.
If ``space.shape`` is 1 in an axis, a corresponding slice of the
phantom is created.
modified : `bool`, optional
True if the modified Shepp-Logan phantom should be given.
The modified phantom has greatly amplified contrast to aid
visualization.
See Also
--------
forbild : Similar phantom but with more complexity. Only supports 2d.
odl.phantom.geometric.defrise : Geometry test phantom
shepp_logan_ellipsoids : Get the parameters that define this phantom
odl.phantom.geometric.ellipsoid_phantom :
Function for creating arbitrary ellipsoid phantoms
References
----------
.. _Shepp-Logan phantom: en.wikipedia.org/wiki/Shepp–Logan_phantom
"""
ellipsoids = shepp_logan_ellipsoids(space.ndim, modified)
return ellipsoid_phantom(space, ellipsoids)
def shepp_logan(space, modified=False):
"""Standard `Shepp-Logan phantom`_ in 2 or 3 dimensions.
Parameters
----------
space : `DiscreteLp`
Space in which the phantom is created, must be 2- or 3-dimensional.
If ``space.shape`` is 1 in an axis, a corresponding slice of the
phantom is created.
modified : `bool`, optional
True if the modified Shepp-Logan phantom should be given.
The modified phantom has greatly amplified contrast to aid
visualization.
See Also
--------
forbild : Similar phantom but with more complexity. Only supports 2d.
odl.phantom.geometric.defrise : Geometry test phantom
shepp_logan_ellipsoids : Get the parameters that define this phantom
odl.phantom.geometric.ellipsoid_phantom :
Function for creating arbitrary ellipsoid phantoms
References
----------
.. _Shepp-Logan phantom: en.wikipedia.org/wiki/Shepp–Logan_phantom
"""
ellipsoids = shepp_logan_ellipsoids(space.ndim, modified)
return ellipsoid_phantom(space, ellipsoids)
def derenzo_sources(space, min_pt=None, max_pt=None):
"""Create the PET/SPECT Derenzo sources phantom.
The Derenzo phantom contains a series of circles of decreasing size.
In 3d the phantom is simply the 2d phantom extended in the z direction as
cylinders.
Parameters
----------
space : `DiscretizedSpace`
Space in which the phantom should be created, must be 2- or
3-dimensional. If ``space.shape`` is 1 in an axis, a corresponding
slice of the phantom is created (instead of squashing the whole
phantom into the slice).
min_pt, max_pt : array-like, optional
If provided, use these vectors to determine the bounding box of the
phantom instead of ``space.min_pt`` and ``space.max_pt``.
It is currently required that ``min_pt >= space.min_pt`` and
``max_pt <= space.max_pt``, i.e., shifting or scaling outside the
original space is not allowed.
Providing one of them results in a shift, e.g., for ``min_pt``::
new_min_pt = min_pt
new_max_pt = space.max_pt + (min_pt - space.min_pt)
Providing both results in a scaled version of the phantom.
Returns
-------
phantom : ``space`` element
The Derenzo source phantom in the given space.
"""
if space.ndim == 2:
return ellipsoid_phantom(space, _derenzo_sources_2d(), min_pt, max_pt)
if space.ndim == 3:
return ellipsoid_phantom(
space, cylinders_from_ellipses(_derenzo_sources_2d()), min_pt,
max_pt)
else:
raise ValueError('dimension not 2, no phantom available')
def shepp_logan(space, modified=False, min_pt=None, max_pt=None):
"""Standard Shepp-Logan phantom in 2 or 3 dimensions.
Parameters
----------
space : `DiscreteLp`
Space in which the phantom is created, must be 2- or 3-dimensional.
If ``space.shape`` is 1 in an axis, a corresponding slice of the
phantom is created.
modified : `bool`, optional
True if the modified Shepp-Logan phantom should be given.
The modified phantom has greatly amplified contrast to aid
visualization.
min_pt, max_pt : array-like, optional
If provided, use these vectors to determine the bounding box of the
phantom instead of ``space.min_pt`` and ``space.max_pt``.
It is currently required that ``min_pt >= space.min_pt`` and
``max_pt <= space.max_pt``, i.e., shifting or scaling outside the
original space is not allowed.
Providing one of them results in a shift, e.g., for ``min_pt``::
new_min_pt = min_pt
new_max_pt = space.max_pt + (min_pt - space.min_pt)
Providing both results in a scaled version of the phantom.
See Also
--------
forbild : Similar phantom but with more complexity. Only supports 2d.
odl.phantom.geometric.defrise : Geometry test phantom
shepp_logan_ellipsoids : Get the parameters that define this phantom
odl.phantom.geometric.ellipsoid_phantom :
Function for creating arbitrary ellipsoid phantoms
References
----------
.. _Shepp-Logan phantom: https://en.wikipedia.org/wiki/Shepp-Logan_phantom
"""
ellipsoids = shepp_logan_ellipsoids(space.ndim, modified)
return ellipsoid_phantom(space, ellipsoids, min_pt, max_pt)
