Programmatically generate video or animated GIF in Python?

I'd recommend not using images2gif from visvis because it has problems with PIL/Pillow and is not actively maintained (I should know, because I am the author).

Instead, please use imageio, which was developed to solve this problem and more, and is intended to stay.

Quick and dirty solution:

import imageio
images = []
for filename in filenames:
    images.append(imageio.imread(filename))
imageio.mimsave('/path/to/movie.gif', images)

For longer movies, use the streaming approach:

import imageio
with imageio.get_writer('/path/to/movie.gif', mode='I') as writer:
    for filename in filenames:
        image = imageio.imread(filename)
        writer.append_data(image)

Well, now I'm using ImageMagick. I save my frames as PNG files and then invoke ImageMagick's convert.exe from Python to create an animated GIF. The nice thing about this approach is I can specify a frame duration for each frame individually. Unfortunately this depends on ImageMagick being installed on the machine. They have a Python wrapper but it looks pretty crappy and unsupported. Still open to other suggestions.

As of June 2009 the originally cited blog post has a method to create animated GIFs in the comments. Download the script images2gif.py (formerly images2gif.py, update courtesy of @geographika).

Then, to reverse the frames in a gif, for instance:

#!/usr/bin/env python

from PIL import Image, ImageSequence
import sys, os
filename = sys.argv[1]
im = Image.open(filename)
original_duration = im.info['duration']
frames = [frame.copy() for frame in ImageSequence.Iterator(im)]    
frames.reverse()

from images2gif import writeGif
writeGif("reverse_" + os.path.basename(filename), frames, duration=original_duration/1000.0, dither=0)

I used images2gif.py which was easy to use. It did seem to double the file size though..

26 110kb PNG files, I expected 26*110kb = 2860kb, but my_gif.GIF was 5.7mb

Also because the GIF was 8bit, the nice png's became a little fuzzy in the GIF

Here is the code I used:

__author__ = 'Robert'
from images2gif import writeGif
from PIL import Image
import os

file_names = sorted((fn for fn in os.listdir('.') if fn.endswith('.png')))
#['animationframa.png', 'animationframb.png', 'animationframc.png', ...] "

images = [Image.open(fn) for fn in file_names]

print writeGif.__doc__
# writeGif(filename, images, duration=0.1, loops=0, dither=1)
#    Write an animated gif from the specified images.
#    images should be a list of numpy arrays of PIL images.
#    Numpy images of type float should have pixels between 0 and 1.
#    Numpy images of other types are expected to have values between 0 and 255.


#images.extend(reversed(images)) #infinit loop will go backwards and forwards.

filename = "my_gif.GIF"
writeGif(filename, images, duration=0.2)
#54 frames written
#
#Process finished with exit code 0

Here are 3 of the 26 frames:

shrinking the images reduced the size:

size = (150,150)
for im in images:
    im.thumbnail(size, Image.ANTIALIAS)