trim-images-script
Script to trim transparent borders from PNG images while keeping the center
aligned. Can process a single file or a whole directory tree.
Requirements
- Python 3.8+
- Pillow
Install Pillow:
pip install Pillow
Supported formats
- PNG (alpha channel required)
- JPEG is detected, but it has no alpha channel, so it will be skipped
Usage
Trim one file:
python trim_images.py path/to/image.png
Trim a folder recursively with 1px padding:
python trim_images.py path/to/folder 1
Padding is recommended (typically 1) to avoid edge flicker during animations.
Windows batch example
The included trim_images.bat runs the script on .\images with 1px padding.
Output
- Each trimmed image is overwritten in place as PNG.
- For every trimmed image, the script prints:
Trim image:(w:<px> h:<px> <absolute_path>) - Total time is printed as:
TIME:<ms>
Notes
- Only images with transparent borders are trimmed.
- If the content touches all sides or the image has no alpha channel, it is skipped.