Using AI to Crop Borders From Images

I have thousands of scanned images which have an unwanted white border around them. The images are of various resolutions and sizes - some portrait, but most are in landscape format. The borders vary in width on every image.
I'm trying to find a way to quickly remove the white border, leaving just the image, in a similar way to how scanner software finds the thumbnail of an image so well (at least, it does if you use Vue Scan).
I thought Capture One AI Crop would be a natural for this, but I can't see how to get it to adapt to different resolutions and formats.
Any help would be most welcome.