You're referring to a tool for repairing corrupted JPEG files!
The JPEG-Repair Toolkit is a specialized utility developed by Joep van Steen (DiskTuna). It was originally created for in-house data recovery services and is now available for public use. The software is unique because it functions more like a than a standard image editor, allowing you to manipulate the underlying data without re-encoding the file, which preserves the original quality. Understanding the "Patch" Functionality jpeg repair ninja patched