Animated GIF image cropping

[urtzai]

When I try to crop animated GIFs with photologue, it seems that only tooks one frame of the entire animation, converting it in a static image. Cropping images is vital in order to keep layout stable but at the same time, users want to upload animated GIFs as banners, autopromotion purposes and other stuff.

Wikimedia commons can do this up to a certain size of image:

"Due to technical limitations, the limit on Wikimedia Commons is width × height × number of frames ≤ 100 million."

e.g. https://commons.wikimedia.org/wiki/File:Eguzki_eklipsea_timelapsea.gif

Implementing this feature would be awesome but if it is not possible, is there any workaround to avoid this behavior? Thank you!

[richardbarran]

I've never thought of using animated GIFs in Photologue so I'm afraid I am of no help... Maybe someone else has experience in this domain and can help?

[erdnaxe]

To crop animated GIF with PIL, you can crop each frame. I implemented something similar here: https://gitlab.crans.org/bde/nk20/-/blob/master/apps/member/forms.py#L100-127

im = Image.open(image)

# Crop each frame
frames = []
for frame in ImageSequence.Iterator(im):
    # processing such as:
    frame = frame.crop((0, 0, 10, 10))
    frames.append(frame)

# Save as GIF
om = frames.pop(0)  # Get first frame
om.info = im.info  # Copy metadata
image.file = io.BytesIO()
om.save(image.file, "GIF", save_all=True, append_images=frames, loop=0)