import matplotlib.pyplot as plt
import numpy as np
from photutils.centroids import centroid_quadratic
from photutils.datasets import make_4gaussians_image

data = make_4gaussians_image()
data -= np.median(data[0:30, 0:125])
data = data[40:80, 70:110]
xycen = centroid_quadratic(data)
fig, ax = plt.subplots(1, 1, figsize=(8, 8))
ax.imshow(data, origin='lower')
ax.scatter(*xycen, color='red', marker='+', s=100, label='Centroid')
ax.legend()