How to Resize Animated GIF Files and Preserve Their Animation with PHP?

Preserving Animation While Resizing Animated GIF Files with PHP

When seeking to alter the dimensions of an animated GIF file, a common concern is preserving its inherent animation. PHP offers a resourceful solution to this challenge.

Utilizing ImageMagick, you can execute the following commands:

system("convert big.gif -coalesce coalesce.gif");
system("convert -size 200x100 coalesce.gif -resize 200x10 small.gif");

Alternatively, you can tap into the ImageMagick plugin, albeit contingent on system() accessibility. Notably, this method may lead to an increase in file size.

For those devoid of ImageMagick access, a multi-step approach using GD is feasible:

1. Employ GD to detect if the image is indeed an animated GIF.
2. Extract the individual frames from the GIF using accessible libraries.
3. Resize each extracted frame independently.
4. Reconstruct the frames into a new animated GIF file.

While more labor-intensive than the ImageMagick approach, this method offers a viable solution if ImageMagick is not an option. If you find success, please consider sharing your experience with the broader community.

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