Apple adopts SynthID for AI-generated images

Apple has integrated SynthID into its latest operating system updates, OS 27.2, to mark images created or edited by AI tools like Image Playground and the new features in the Photos app. This marking helps identify AI-generated content, making it easier to distinguish between human-made and machine-generated images.

SynthID is an invisible watermark

SynthID is a system introduced by Google over three years ago that adds an imperceptible watermark to AI-generated images. This watermark is embedded in the image’s pixels and is invisible to the human eye but detectable by computers, helping to track the origin of the image.

Google's portal detects SynthID content

Google has set up a public portal that can detect SynthID-marked images, allowing users to check if an image was generated or edited by AI. This tool helps verify the authenticity of images and is part of an effort to increase transparency in AI-generated content.

SynthID works across Apple platforms

Tests show that SynthID functions effectively with Image Playground on macOS 27.2 and iOS 27.2, and with the Photos app on iOS 27.2. However, detection of edited images in Photos on Mac was not successful in initial tests, suggesting that this issue may be addressed in future updates.

SynthID is more secure than metadata

Apple has chosen SynthID over traditional metadata for marking AI-edited images because metadata can be easily removed. Tests confirmed that even after removing EXIF data or taking screenshots, the SynthID watermark remained intact and detectable by Google’s portal.

Modifications can affect SynthID detection

While SynthID is robust, strongly modifying an image—such as cropping it significantly—can make the watermark undetectable. However, simpler changes like adjusting color or adding grain did not disrupt the watermark, indicating that it is relatively resilient to common edits.

Apple's AI tools use Google's LLMs

Apple’s AI models used in Image Playground and the Photos app are based on Google’s large language models. This allows Apple to integrate advanced AI features without developing the underlying models from scratch, streamlining the development process.

SynthID is added automatically

The SynthID watermark is automatically added when users use AI tools in Image Playground or the three new editing features in Photos: correct, extend, and reorient. These tools rely on Apple’s cloud-based servers, which are capable of generating large areas of an image, unlike the local editing tools that only modify existing pixels.