Developer Xusheng Li has uncovered some previously unknown functionality deep within Microsoft’s Paint and Photos apps. The findings concern GUID watermarks. While these programs clearly add Copilot logo watermarks to images where LLM image generation has played a part in the process, Li also uncovered an invisible watermark and the process behind embedding it. To be clear, both these watermarks are merely to identify/verify imagery where AI has had a role in the creation, so GUID should not be confused with the recent controversies over Microsoft’s GDID traceable device-specific telemetry.
Li says that simple curiosity spurred him to investigate the AI features of the Paint app in Windows 11. The image generation functionality being capable of calling a remote API was expected. However, the dev got more curious when four apparent model files were found in the app path for local processing. Specifically, one of the local files was an ONNX-like model, the other 3 were encrypted ONNX-like files…
