etomo.operators.fourier.utils#

Functions to transform data from radon space to fourier space (only in 2D for now). Density compensation taken from pysap-mri.

generate_locations_etomo_2D(size_x, angles)[source]#

This function generates the list of the samples coordinate in the k-space.

Parameters

  • size_x (int) – image size along the x-axis

  • angles (numpy.ndarray(q)) – array countaining the acquisition angles

Returns

samples – Fourier space locations generated from the given angles and data image size

Return type

numpy.ndarray((size_x * q, 2))

generate_kspace_etomo_2D(sinogram)[source]#

This function generates the list of the kspace observations.

Parameters

sinogram (numpy.ndarray((q, m))) – sinogram with size nb_angles and size_x (m)

Returns

kspace_obs – Fourier space values from the given sinogram

Return type

numpy.ndarray((q*int(m*sqrt(2)))

estimate_density_compensation(kspace_loc, volume_shape, num_iterations=10)[source]#

Utils function to obtain the density compensator for a given set of kspace locations.

Parameters

  • kspace_loc (numpy.ndarray) – the kspace locations

  • volume_shape (numpy.ndarray) – the volume shape

  • num_iterations (int, default 10) – the number of iterations for density estimation