import numpy as np
from .fbp import Backprojector
from .reconstructor import Reconstructor
class CudaReconstructor(Reconstructor):
def __init__(self, shape, indices, axis="z", vol_type="sinograms", slices_roi=None, **backprojector_options):
Reconstructor.__init__(self, shape, indices, axis=axis, vol_type=vol_type, slices_roi=slices_roi)
self._init_backprojector(**backprojector_options)
def _init_backprojector(self, **backprojector_options):
self.backprojector = Backprojector(
self.sinos_shape[1:], slice_roi=self.backprojector_roi, **backprojector_options
)
def reconstruct(self, data, output=None):
"""
Reconstruct from sinograms or projections.
"""
self._check_data(data)
B = self.backprojector
if output is None:
output = np.zeros(self.output_shape, "f")
new_output = True
else:
assert output.shape == self.output_shape, str(
"Expected output_shape = %s, got %s" % (str(self.output_shape), str(output.shape))
)
assert output.dtype == np.float32
new_output = False
def reconstruct_fbp(data, output, i, i0):
if self.vol_type == "sinograms":
current_sino = data[i]
else:
current_sino = data[:, i, :]
if new_output:
output[i0] = B.fbp(current_sino)
else:
B.fbp(current_sino, output=output[i0])
for i0, i in enumerate(self._z_indices):
reconstruct_fbp(data, output, i, i0)
return output