def METHOD_NAME(self, data):
    if not isinstance(data, AcquisitionData):
        raise Exception('Processor supports only AcquisitionData')
    if data.geometry == None:
        raise Exception('Geometry is not defined.')
    if data.geometry.geom_type == 'cone':
        raise ValueError("Only parallel-beam data is supported with this algorithm")
    if data.geometry.channels > 1:
        raise ValueError("Only single channel data is supported with this algorithm")
    if self.slice_index != 'centre':
        try:
            int(self.slice_index)
        except:
            raise ValueError("slice_index expected to be a positive integer or the string 'centre'. Got {0}".format(self.slice_index))
        if self.slice_index < 0 or self.slice_index >= data.get_dimension_size('vertical'):
            raise ValueError('slice_index is out of range. Must be in range 0-{0}. Got {1}'.format(data.get_dimension_size('vertical'), self.slice_index))
    if self.projection_index >= data.geometry.config.angles.num_positions:
            raise ValueError('projection_index is out of range. Must be less than {0}. Got {1}'.format(data.geometry.config.angles.num_positions, self.projection_index))
    return True