If all else fails, you can use Imager, and the ->getwidth, ->getheight and ->getpixel methods to read the image pixel by pixel to find the leftmost non-alpha pixel and the rightmost non-alpha pixel (and top/bottom), and then use ->crop to crop the image.

In reply to Re: Detect boundaries within .png's - and cropping by Corion
in thread Detect boundaries within .png's - and cropping by Stickybit

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