Using PyLab's Specgram In A Headless Environment [duplicate]

Question

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Generating a PNG with matplotlib when DISPLAY is undefined (13 answers)

Closed 6 years ago.

Anyone know how to get it working? Unfortunately it seems by default specgram's code wants to generate an image, which I have no use for, only the data behind the image. The error I get is:

_tkinter.TclError: no display name and no $DISPLAY environment variable

Answer 1

You may set a matplotlib backend, which doesn't need a display attached:

import matplotlib
matplotlib.use('pdf')

These lines should go before importing pylab.