How to use custom png image marker with plot?

Question

I would like to utilize customer markers in both scatter and line charts. How can I make custom marker out of a PNG file?

Answer 1

The other answer may lead to problems when resizing the figure. Here is a different approach, positionning the images inside annotation boxes, which are anchored in data coordinates.

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.offsetbox import OffsetImage, AnnotationBbox

path = "https://upload.wikimedia.org/wikipedia/commons/b/b5/Tango-example_icons.png"
image = plt.imread(path)[116:116+30, 236:236+30]

x = np.arange(10)
y = np.random.rand(10)

fig, ax = plt.subplots()
ax.plot(x,y)

def plot_images(x, y, image, ax=None):
    ax = ax or plt.gca()

    for xi, yi in zip(x,y):
        im = OffsetImage(image, zoom=72/ax.figure.dpi)
        im.image.axes = ax

        ab = AnnotationBbox(im, (xi,yi), frameon=False, pad=0.0,)

        ax.add_artist(ab)

plot_images(x, y, image, ax=ax)

plt.show()