PNG Pixel Authenticator

This is a web application that verifies tampering of copyrighted images on a pixel-by-pixel basis for PNG images.
It is a tool that allows you to investigate yourself for the possibility that your copyrighted images have been 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 outside will be detected.
If you leak the key externally, when comparing potentially tampered images with your registered images, they may be forged.