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Reference for pyronn/ct_reconstruction/layers/tensorflow/backprojection_3d.py


pyronn.ct_reconstruction.layers.tensorflow.backprojection_3d.cone_backprojection3d 

cone_backprojection3d(sinogram, geometry, hardware_interp=True)

Wrapper function for making the layer call. Args: volume: Input volume to project. geometry: Corresponding GeometryCone3D Object defining parameters. hardware_interp: Controls if interpolation is done by GPU Returns: Initialized lme_custom_ops.cone_backprojection3d layer.

Source code in pyronn/ct_reconstruction/layers/tensorflow/backprojection_3d.py 
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def cone_backprojection3d(sinogram, geometry, hardware_interp=True):
    """
    Wrapper function for making the layer call.
    Args:
        volume:             Input volume to project.
        geometry:           Corresponding GeometryCone3D Object defining parameters.
        hardware_interp:    Controls if interpolation is done by GPU 
    Returns:
            Initialized lme_custom_ops.cone_backprojection3d layer.
    """
    batch = np.shape(sinogram)[0]
    step_size=1.0
    return pyronn_layers.cone_backprojection3d(sinogram,
                                               volume_shape=geometry.volume_shape,
                                               volume_origin=np.broadcast_to(geometry.volume_origin, [batch, *np.shape(geometry.volume_origin)]),
                                               volume_spacing=np.broadcast_to(geometry.volume_spacing, [batch, *np.shape(geometry.volume_spacing)]),
                                               projection_matrices=np.broadcast_to(geometry.trajectory, [batch, *np.shape(geometry.trajectory)]),
                                               hardware_interp=hardware_interp,
                                               step_size=np.broadcast_to(step_size, [batch, *np.shape(step_size)]),
                                               projection_multiplier=np.broadcast_to(geometry.projection_multiplier, [batch, *np.shape(geometry.projection_multiplier)]))




pyronn.ct_reconstruction.layers.tensorflow.backprojection_3d._backproject_grad 

_backproject_grad(op, grad)

Compute the gradient of the backprojector op by invoking the forward projector.

Source code in pyronn/ct_reconstruction/layers/tensorflow/backprojection_3d.py 
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@ops.RegisterGradient("ConeBackprojection3D")
def _backproject_grad(op, grad):
    # TODO: Document this function on your own. Could not be documented by the model.
    # TODO: Document this function on your own. Could not be documented by the model.
    '''
        Compute the gradient of the backprojector op by invoking the forward projector.
    '''
    proj = pyronn_layers.cone_projection3d(
        volume=grad,
        projection_shape=op.inputs[0].shape[1:],
        volume_origin=op.inputs[2],
        volume_spacing=op.inputs[3],
        projection_matrices=op.inputs[4],
        hardware_interp=op.get_attr("hardware_interp"),
        step_size=op.inputs[5],
        projection_multiplier=op.inputs[6],
    )
    return [proj, tf.stop_gradient(op.inputs[1]), tf.stop_gradient(op.inputs[2]), tf.stop_gradient(op.inputs[3]), tf.stop_gradient(op.inputs[4]), tf.stop_gradient(op.inputs[5]), tf.stop_gradient(op.inputs[6])]