def process(self):
        
        volume = self.get_input()
        volume_axes = volume.get_data_axes_order(new_order=self.default_image_axes_order)
        if not volume_axes == [0,1,2]:
            volume.array = numpy.transpose(volume.array, volume_axes)
        pixel_per_voxel = 1 # should be estimated from image_geometry and 
                            # acquisition_geometry
        if self.acquisition_geometry.geom_type == 'parallel':

            pixels = pbalg.pb_forward_project(volume.as_array(), 
                                                  self.acquisition_geometry.angles, 
                                                  pixel_per_voxel)
            out = AcquisitionData(geometry=self.acquisition_geometry, 
                                  label_dimensions=self.default_acquisition_axes_order)
            out.fill(pixels)
            out_axes = out.get_data_axes_order(new_order=self.output_axes_order)
            if not out_axes == [0,1,2]:
                out.array = numpy.transpose(out.array, out_axes)
            return out
        else:
            raise ValueError('Cannot process cone beam')
示例#2
0
from ccpi.optimisation.algs import CGLS

import numpy

# Set up reader object and read the data
datareader = XTEKReader("REPLACE_THIS_BY_PATH_TO_DATASET/SophiaBeads_256_averaged.xtekct")
data = datareader.get_acquisition_data()

# Crop data and fix dimension labels
data = AcquisitionData(data.array[:,:,901:1101],
                            geometry=data.geometry,
                            dimension_labels=['angle','horizontal','vertical'])
data.geometry.pixel_num_v = 200

# Scale and negative-log transform
data.array = -np.log(data.as_array()/60000.0)

# Apply centering correction by zero padding, amount found manually
cor_pad = 30
data_pad = np.zeros((data.shape[0],data.shape[1]+cor_pad,data.shape[2]))
data_pad[:,cor_pad:,:] = data.array
data.geometry.pixel_num_h = data.geometry.pixel_num_h + cor_pad
data.array = data_pad

# Choose the number of voxels to reconstruct onto as number of detector pixels
N = data.geometry.pixel_num_h

# Geometric magnification
mag = (np.abs(data.geometry.dist_center_detector) + \
      np.abs(data.geometry.dist_source_center)) / \
      np.abs(data.geometry.dist_source_center)