PNG Pixel Authenticator

This is a web application that verifies tampering of copyrighted images on a pixel-by-pixel basis compatible with PNG images.
It is a tool that allows you to investigate yourself for the possibility of your copyrighted images being tampered with by others when you post images on the internet.
You authenticate with a passkey and generate a key (.sig) file for each individual image, so please do not leak the key externally.
If a PNG file is tampered with even slightly, verification will fail and tampering externally will be detected.
If you leak the key externally, when comparing a possibly tampered image with your registered image, it may be forged.