skued.autocenter¶
- skued.autocenter(im, mask=None)¶
Find the center of a diffraction pattern automatically.
New in version 2.1.1.
- Parameters
im (ndarray, shape (N, M)) – Diffraction pattern.
mask (ndarray, shape (N,M), dtype bool, optional) – Mask that evaluates to True on pixels that should be used to determine the center.
- Returns
r, c – Indices of the center, such that
im[r, c]
is the intensity value at the center of the pattern.- Return type
2-tupe of ints
Notes
The procedure in this routine is an extension of the one in the reference below. It has been adapted for both single-crystal and polycrystalline diffraction patterns The continuous inversion symmetry is encoded as the coordinate transformation \((r, \theta) \to (-r, \theta)\). The shift between the image and inverted image determines the correction to the approximate center found by calculating the intensity center-of-mass.
References
Liu, Lai Chung. Chemistry in Action: Making Molecular Movies with Ultrafast Electron Diffraction and Data Science, Chapter 2. Springer Nature, 2020.