def _backproject_block(self, proj_data, proj_geom, vol_data, vol_geom,
algorithm):
'''
Backproject a single block of data
'''
# TODO:
# Do we need to introduce ShortScan parameter?
# At the moment we will ignore MinConstraint / MaxConstraint
try:
sin_id = astra.data3d.link('-sino', proj_geom,
numpy.ascontiguousarray(proj_data))
vol_id = astra.data3d.link('-vol', vol_geom, vol_data)
projector_id = astra.create_projector('cuda3d', proj_geom,
vol_geom)
if algorithm == 'BP3D_CUDA':
asex.accumulate_BP(projector_id, vol_id, sin_id)
elif algorithm == 'FDK_CUDA':
asex.accumulate_FDK(projector_id, vol_id, sin_id)
else:
raise ValueError('Unknown ASTRA algorithm type.')
except:
print("ASTRA error:", sys.exc_info())
finally:
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
astra.projector.delete(projector_id)
return vol_data
def _backproject_block_mult_( projections, volume, proj_geom, vol_geom):
"""
Multiplicative backprojection of a single block.
"""
try:
# Need to create a copy of the volume:
volume_ = numpy.zeros_like(volume)
sin_id = astra.data3d.link('-sino', proj_geom, projections)
vol_id = astra.data3d.link('-vol', vol_geom, volume_)
projector_id = astra.create_projector('cuda3d', proj_geom, vol_geom)
# We are using accumulate version to avoid creating additional copies of data.
asex.accumulate_BP(projector_id, vol_id, sin_id)
except:
# The idea here is that we try to delete data3d objects even if ASTRA crashed
try:
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
finally:
info = sys.exc_info()
traceback.print_exception(*info)
volume *= volume_
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
def _backproject_block_add_(projections,
volume,
proj_geom,
vol_geom,
algorithm='BP3D_CUDA',
negative=False):
"""
Additive backprojection of a single block.
Use negative = True if you want subtraction instead of addition.
"""
try:
if negative:
projections *= -1
# If volume is a memmap - create a temporary copy in RAM
if isinstance(volume, numpy.memmap):
vol_temp = numpy.ascontiguousarray(volume)
vol_id = astra.data3d.link('-vol', vol_geom, vol_temp)
else:
vol_id = astra.data3d.link('-vol', vol_geom, volume)
sin_id = astra.data3d.link('-sino', proj_geom, projections)
projector_id = astra.create_projector('cuda3d', proj_geom, vol_geom)
# We are using accumulate version to avoid creating additional copies of data.
if algorithm == 'BP3D_CUDA':
asex.accumulate_BP(projector_id, vol_id, sin_id)
elif algorithm == 'FDK_CUDA':
asex.accumulate_FDK(projector_id, vol_id, sin_id)
else:
raise ValueError('Unknown ASTRA algorithm type.')
if isinstance(volume, numpy.memmap):
volume[:] = vol_temp
except:
# The idea here is that we try to delete data3d objects even if ASTRA crashed
try:
if negative:
projections *= -1
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
finally:
info = sys.exc_info()
traceback.print_exception(*info)
if negative:
projections *= -1
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
def _backproject_block_(projections,
volume,
proj_geom,
vol_geom,
algorithm='BP3D_CUDA',
operation='+'):
"""
Use this internal function to compute backprojection of a single block of data.
"""
try:
if (operation == '+'):
volume_ = volume
elif (operation == '*') | (operation == '/'):
volume_ = np.zeros_like(volume)
else:
ValueError('Unknown operation type!')
sin_id = astra.data3d.link('-sino', proj_geom, projections)
vol_id = astra.data3d.link('-vol', vol_geom, volume_)
projector_id = astra.create_projector('cuda3d', proj_geom, vol_geom)
if algorithm == 'BP3D_CUDA':
asex.accumulate_BP(projector_id, vol_id, sin_id)
elif algorithm == 'FDK_CUDA':
asex.accumulate_FDK(projector_id, vol_id, sin_id)
else:
raise ValueError('Unknown ASTRA algorithm type.')
if (operation == '*'):
volume *= volume_
elif (operation == '/'):
volume_[volume_ < 1e-10] = numpy.inf
volume /= volume_
except:
print("ASTRA error:", sys.exc_info())
finally:
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)
def _backproject_block_(projections, volume, proj_geom, vol_geom, algorithm = 'BP3D_CUDA', operation = '+'):
"""
Use this internal function to compute backprojection of a single block of data.
"""
# Unfortunately need to hide the experimental ASTRA
import astra.experimental as asex
try:
if (operation == '+'):
volume_ = volume
elif (operation == '*') | (operation == '/'):
volume_ = numpy.zeros_like(volume)
else: ValueError('Unknown operation type!')
sin_id = astra.data3d.link('-sino', proj_geom, projections)
vol_id = astra.data3d.link('-vol', vol_geom, volume_)
projector_id = astra.create_projector('cuda3d', proj_geom, vol_geom)
if algorithm == 'BP3D_CUDA':
asex.accumulate_BP(projector_id, vol_id, sin_id)
elif algorithm == 'FDK_CUDA':
asex.accumulate_FDK(projector_id, vol_id, sin_id)
else:
raise ValueError('Unknown ASTRA algorithm type.')
if (operation == '*'):
volume *= volume_
#flexUtil.display_slice(volume, dim = 0, title = 'worm')
# This is really slow but needed in case of overlap for EM:
volume_ *= 0
astra.data3d.delete(sin_id)
sin_id = astra.data3d.link('-sino', proj_geom, projections * 0 + 1)
asex.accumulate_BP(projector_id, vol_id, sin_id)
#flexUtil.display_slice(volume_, dim = 0, title = 'norm')
volume_[volume_ < 0.01] = 0.01
volume /= volume_
#flexUtil.display_slice(volume, dim = 0, title = 'rorm')
elif (operation == '/'):
volume_[volume_ < 1e-3] = numpy.inf
volume /= volume_
except:
print("ASTRA error:", sys.exc_info())
finally:
astra.algorithm.delete(projector_id)
astra.data3d.delete(sin_id)
astra.data3d.delete(vol_id)