testing PyAbel abel/tools/center.py/set_center()

test_center_valid.py

import numpy as np
import abel
import matplotlib.pyplot as plt
from scipy.ndimage.interpolation import shift

fig, ax = plt.subplots(2, 2, figsize=(8, 8))

n = 201
n2 = n//2
geo_origin = (n2, n2)
im = abel.tools.analytical.SampleImage(n).image

# edges
im[:, 0] = 100
im[:, n-1] = 100
im[0, :] = 100
im[n-1, :] = 100

vm = im.max()
# rescale central intensity
radius = n // 10
for r in range(-radius, radius, 1):
    for c in range(-radius, radius, 1):
        if r**2 + c**2 < radius**2:
            im[n2+r, n2+c] /= 25 
            # add some near edge data
            im[radius+r//4, radius+c//4] = vm//45
            im[n-radius+r//4, n-radius+c//4] = vm//40
            im[radius+r//4, n-radius+c//4] = vm//35
            im[n-radius+r//4, radius+c//4] = vm//30

# offset
dr = 20
dc = 20

imx = shift(im, (dr, dc))  # origin now (n2+dr, n2+dc)


ax0 = ax[0, 0]
ax0.imshow(imx)
ax0.set_title(f'original ({n2+dr}, {n2+dc}) {imx.shape}', fontsize='small')
ax0.plot((0, n), (n2, n2), 'r', lw=1)
ax0.plot((n2, n2), (0, n), 'r', lw=1)
ax0.axis(xmin=0, xmax=n, ymin=n, ymax=0)

i = 0
for crop in ['maintain_size', 'valid_region', 'maintain_data']:
    # PyAebl reset image center to origin
    imc = abel.tools.center.set_center(imx, (n2+dr, n2+dc),
                                       crop=crop, axes=(0, 1))
    i += 1

    r, c = imc.shape
    r2 = r//2
    c2 = c//2
    axi = ax[i//2, i%2]
    axi.imshow(imc)
    axi.plot((0, r), (r2, c2), 'r', lw=1)
    axi.plot((r2, c2), (0, c), 'r', lw=1)
    if crop == 'valid_region':
        axi.axis(xmin=0, xmax=n, ymin=n, ymax=0)
    else:
        axi.axis(xmin=0, xmax=c, ymin=r, ymax=0)
    axi.set_title(f'{crop} ({n2}, {n2}) {imc.shape}', fontsize='small')

plt.show()