import matplotlib.pyplot as plt
import numpy as np
from photutils.centroids import centroid_2dg, centroid_sources
from photutils.datasets import make_4gaussians_image

data = make_4gaussians_image()
data -= np.median(data[0:30, 0:125])
x_init = (25, 91, 151, 160)
y_init = (40, 61, 24, 71)
x, y = centroid_sources(data, x_init, y_init, box_size=25,
                        centroid_func=centroid_2dg)
fig, ax = plt.subplots(figsize=(8, 4))
ax.imshow(data, origin='lower')
ax.scatter(x, y, marker='+', s=80, color='red', label='Centroids')
ax.legend()
fig.tight_layout()