tomodrgn.fft.symmetrize_ht

symmetrize_ht(batched_ht_imgs: ndarray, preallocated: bool = False) → ndarray

Mirror-pads an even-box DHT image (stack) such that DC is at D//2,D//2 and highest frequency is at both D//2,0 and D//2,D

Parameters:

• batched_ht_imgs – DHT-transformed image stack (such as from fft.ht3_center), shape ([N], D, D) or ([N], D+1, D+1)

• preallocated – whether the input batched_ht_imgs last two dimensions are each padded one pixel larger than the input image to accomodate mirroring. Symmetrizing the centered DHT involves mirroring the left-most column and top-most row of each image to the right-most column and bottom-most row.

Returns:

np.ndarray of symmetrized and centered DHT-transformed images, shape ([N], D+1, D+1)