matplotlib save animation in gif error

Question

I want to save matplotlib animation in gif format.

I succeded to save animation to mp4 format, using code

import matplotlib
matplotlib.use("Agg")

~some codes~

ani = animation.FuncAnimation(fig, draw, update, interval=10, blit=False)
mywriter = animation.FFMpegWriter(fps=60)
ani.save('myanimation.mp4',writer=mywriter)

but if I change myanimation.mp4 to gif format, python makes error

Traceback (most recent call last):
  File "C:\Users\Administrator\Desktop\edison\Edison_v4_backup_1\ver5.py", line 164, in <module>
    ani.save('demoanimation.gif',writer=mywriter);
  File "C:\Python27\lib\site-packages\matplotlib\animation.py", line 718, in save
    writer.grab_frame(**savefig_kwargs)
  File "C:\Python27\lib\site-packages\matplotlib\animation.py", line 204, in grab_frame
    dpi=self.dpi, **savefig_kwargs)
  File "C:\Python27\lib\site-packages\matplotlib\figure.py", line 1421, in savefig
    self.canvas.print_figure(*args, **kwargs)
  File "C:\Python27\lib\site-packages\matplotlib\backend_bases.py", line 2220, in print_figure
    **kwargs)
  File "C:\Python27\lib\site-packages\matplotlib\backends\backend_agg.py", line 497, in print_raw
    renderer._renderer.write_rgba(filename_or_obj)
RuntimeError: Error writing to file

Seeing that I succeded to save in mp4 format, I don't know why it makes error when saving gif format.

score 30 · Accepted Answer · answered Aug 05 '14 at 16:15

30

This is because matplotlib does not support GIFs without external programs. If you have imagemagick correctly installed and configured, this should work:

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
import matplotlib.animation
import numpy as np


def init_animation():
    global line
    line, = ax.plot(x, np.zeros_like(x))
    ax.set_xlim(0, 2*np.pi)
    ax.set_ylim(-1,1)

def animate(i):
    line.set_ydata(np.sin(2*np.pi*i / 50)*np.sin(x))
    return line,

fig = plt.figure()
ax = fig.add_subplot(111)
x = np.linspace(0, 2*np.pi, 200)

ani = matplotlib.animation.FuncAnimation(fig, animate, init_func=init_animation, frames=50)
ani.save('/tmp/animation.gif', writer='imagemagick', fps=30)

enter image description here

answered Aug 05 '14 at 16:15

DrV

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This wokrs well. but can I reduce imagemagick file size? my program is just ~20kb but Imagemagick is about 60mb... I only need gif change feature in imagemagick. do you have any idea? – user42298 Aug 05 '14 at 16:56
@user42298 I had a similar experience when animating a 3D plot. The axis and background grid were plotted and took most of the space. Removing these elements gave a nice and small animation. Out-of-the-box, gifs generated with ImageMagick have far better resolution than mp4s generated with ffmpeg. I hope this helps. – user989762 Dec 03 '14 at 02:26
I get `File "C:\Python27\lib\site-packages\matplotlib\backends\backend_agg.py", line 513, in print_raw renderer._renderer.write_rgba(filename_or_obj) RuntimeError: Error writing to file` running this script in Windows 7 – endolith Aug 07 '15 at 03:14
is it possible to do this using more than one core? I am saving hundreds of videos. – crypdick Jul 17 '18 at 23:09

score 7 · Answer 2 · edited Mar 26 '18 at 11:30

7

Just a reminder, before you use Matplotlib and ImageMagick to convert images or videos to gif, you need to modify Matplotlib's config and add ImageMagick's path.

The following code will show you the config file path of Matplotlib

import matplotlib
matplotlib.matplotlib_fname()

For me the path is

C:\Anaconda\lib\site-packages\matplotlib\mpl-data\matplotlibrc

Then changing animation.convert_path

#animation.convert_path: 'convert' # Path to ImageMagick's convert binary.
                                   # On Windows use the full path since convert
                                   # is also the name of a system tool.

by adding convert.exe path to it

animation.convert_path: C:\Program Files\ImageMagick-6.9.2-Q16-HDRI\convert.exe

Don't forget to remove the # before animation.convert_path.

After the above modification, Matplotlib and ImageMagick will perfectly work and output the gif file you want.

example gif

Hope it helps.

edited Mar 26 '18 at 11:30

Elias Strehle

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answered Feb 17 '16 at 06:01

Eric

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This helped me a lot! Used it on Mac OS X, except for the convert.exe ;) – Sander van den Oord Nov 15 '16 at 13:53
Could you elaborate @SandervandenOord. I can't get this going with my Mac. Did you just drop the `convert.exe`. As such, `animation.convert_path: C:\Program Files\ImageMagick-6.9.2-Q16-HDRI` – jonboy Mar 31 '20 at 07:46
@jonboy This was 3+ years ago, so I don't know exactly anymore. But a .exe is a windows file, so I guess yes that part should be left out. – Sander van den Oord Mar 31 '20 at 11:17
@jonboy You can also still try my answer I gave below, which has 0 upvotes ;) – Sander van den Oord Mar 31 '20 at 15:23
Thanks. I gave it a go to no avail. I was wondering if I was missing something else. – jonboy Mar 31 '20 at 21:30

score 3 · Answer 3 · answered Nov 17 '16 at 10:34

Still had some trouble on Mac OS X, but the answers above pointed me in the right direction.

What I did came down to:

brew install imagemagick
edit the path file on location /etc/path (sudo vim path) and added the location of bin folder of imagemagick, in my case: /usr/local/Cellar/imagemagick/6.9.6-4/bin
changed the settings of matplotlibrc as described above. You can find the location of matplotlibrc by doing in Python: import matplotlib matplotlib.matplotlib_fname() The settings you need to adjust can be found at the end of the file. I adjusted the following ones (commented out). Please note that those settings are not in 'quotes':

animation.writer : imagemagick

animation.codec : mpeg4

animation.bitrate: -1

animation.frame_format: png

animation.convert_path: convert

score 2 · Answer 4 · answered Aug 07 '15 at 03:46

DrV's script didn't work for me on Windows 7, even though convert and ffmpeg both are in the system path.

  File "C:\Python27\lib\site-packages\matplotlib\backends\backend_agg.py", line 513, in print_raw
    renderer._renderer.write_rgba(filename_or_obj)

RuntimeError: Error writing to file

C:\Users>ffmpeg
ffmpeg version N-50911-g9efcfbe Copyright (c) 2000-2013 the FFmpeg developers
   ...

C:\Users>convert
Version: ImageMagick 6.9.1-1 Q16 x64 2015-03-20 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2015 ImageMagick Studio LLC
   ...

Editing my matplotlibrc to add the full path to the exe fixed it:

###ANIMATION settings
#animation.html : 'none'           # How to display the animation as HTML in
                                   # the IPython notebook. 'html5' uses
                                   # HTML5 video tag.
#animation.writer : ffmpeg         # MovieWriter 'backend' to use
#animation.codec : mpeg4           # Codec to use for writing movie
#animation.bitrate: -1             # Controls size/quality tradeoff for movie.
                                   # -1 implies let utility auto-determine
#animation.frame_format: 'png'     # Controls frame format used by temp files
animation.ffmpeg_path: C:\Program Files\ImageMagick-6.9.1-Q16\ffmpeg.exe   # Path to ffmpeg binary. Without full path
                                   # $PATH is searched
#animation.ffmpeg_args: ''         # Additional arguments to pass to ffmpeg
#animation.avconv_path: 'avconv'   # Path to avconv binary. Without full path
                                   # $PATH is searched
#animation.avconv_args: ''         # Additional arguments to pass to avconv
#animation.mencoder_path: 'mencoder'
                                   # Path to mencoder binary. Without full path
                                   # $PATH is searched
#animation.mencoder_args: ''       # Additional arguments to pass to mencoder
animation.convert_path: C:\Program Files\ImageMagick-6.9.1-Q16\convert.exe # Path to ImageMagick's convert binary.
                                   # On Windows use the full path since convert
                                   # is also the name of a system tool.

score 1 · Answer 5 · edited Jun 08 '21 at 08:36

1

I have just tried to install ffmpeg, didn't help. Then I tried to install imagemagick - failed. So I resorted to looping animation and recording it with screen scraper . I use ScreenToGif.

edited Jun 08 '21 at 08:36

DisappointedByUnaccountableMod

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answered Jan 06 '19 at 11:47

Yola

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matplotlib save animation in gif error

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