SynthID

2 min read Original article ↗

SynthID

A tool to watermark and identify content generated through AI


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AI-generated image and video

SynthID adds an invisible digital watermark to an AI-generated image (or video segment). The watermark doesn’t change the image or video quality. It’s added the moment content is created, and designed to stand up to modifications like cropping, adding filters, changing frame rates, or lossy compression.

AI-generated audio

SynthID embeds a watermark into any audio generated or published through our AI music generation model Lyria or the podcast generation feature of Notebook LM. It’s inaudible to the human ear, and can’t be altered by common modifications like adding noise, MP3 compression, or changing the speed of the track.

AI generated-text

We’ve expanded SynthID to watermarking and identifying text generated by the Gemini app and web experience. Large language models generate text one word (token) at a time. Each word is assigned a probability score, based on how likely it is to be generated next. So for a sentence like “My favourite tropical fruits are mango and…”, the word “bananas” would have a higher probability score than the word “airplanes”. SynthID adjusts these probability scores to generate a watermark. It's not noticeable to the human eye, and doesn’t affect the quality of the output.