Comment by alibero

I've been looking into this. There seems to be some mostly-repeating 2D pattern in the LSB of the generated images. The magnitude of the noise seems to be larger in the pure black image vs pure white image. My main goal is to doctor a real image to flag as positive for SynthID, but I imagine if you smoothed out the LSB, you might be able to make images (especially very bright images) no longer flag as SynthID? Of course, it's possible there's also noise in here from the image-generation process...

Gemini really doesn't like generating pure-white images but you can ask it to generate a "photograph of a pure-white image with a black border" and then crop it. So far I've just been looking at pure images and gradients, it's possible that more complex images have SynthID embedded in a more complicated way (e.g. a specific pattern in an embedding space).