How to insert a small image on the corner of a plot with matplotlib?

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What I want is really simple: I have a small image file called "logo.png" that I want to display on the upper left corner of my plots. But you can't find any example of that in the matplotlib examples gallery.

I'm using django, and my code is something like this:

def get_bars(request)
    ...
    fig = Figure(facecolor='#F0F0F0',figsize=(4.6,4))
    ...
    ax1 = fig.add_subplot(111,ylabel="Valeur",xlabel="Code",autoscale_on=True)
    ax1.bar(ind,values,width=width, color='#FFCC00',edgecolor='#B33600',linewidth=1)
    ...
    canvas = FigureCanvas(fig)
    response = HttpResponse(content_type='image/png')
    canvas.print_png(response)
    return response
matplotlib image django python
2 Answers

There is now a much easier way, using the new inset_axes command (matplotlib >3.0 required).

This command allows one to define a new set of axes as a child of an existing axes object. The advantage of this is that you can define your inset axes in whatever units you please, like axes fraction or data coordinates, using the appropriate transform expression.

So here's a code example:

# Imports
import matplotlib.pyplot as plt
import matplotlib as mpl

# read image file
with mpl.cbook.get_sample_data(r"C:\path\to\file\image.png") as file:
arr_image = plt.imread(file, format='png')

# Draw image
axin = ax.inset_axes([105,-145,40,40],transform=ax.transData)    # create new inset axes in data coordinates
axin.imshow(arr_image)
axin.axis('off')

The advantage of this method is that your image will scale automatically as your axes get rescaled!

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