Side-by-side comparison
| Visible Gemini watermark | SynthID | |
|---|---|---|
| Can you see it? | Yes, a small sparkle near the bottom-right corner | No, it is hidden in the pixels |
| Purpose | A quick visual label | Lets Google-provided tools identify AI-generated content |
| Where it lives | One small area | Spread across the whole image |
| Designed to survive edits? | No, cropping removes it | Yes, designed to withstand common edits such as cropping and compression |
| Removed by Imaginoa? | Yes | No |
The visible sparkle
The sparkle is a semi-transparent white shape blended into a corner. Gemini has used an older, brighter version close to the corner and a newer, fainter version placed further in. Because the mark is blended with a known shape and strength, tools like Imaginoa can reverse the blend and restore the original pixels.
SynthID
SynthID is Google DeepMind's invisible watermarking technology. Instead of a logo, it makes tiny changes throughout the image that people cannot notice but detection tools can. It is built to remain detectable after everyday edits, which is why removing the visible sparkle does not change whether the image can be identified as AI-generated.
Why this matters
- For creators: removing the sparkle can make a thumbnail or slide look cleaner, but the image is still AI-generated.
- For honesty: be open about AI images where your audience, client or platform expects it.
- For rights: only edit images you created or have permission to change.
Free and private. Your image never leaves your device.
A third layer: Content Credentials
Most articles stop at two marks. There is usually a third, and it behaves differently from both.
Content Credentials, built on the C2PA standard, are a signed record attached to the file: what made the image, when, and sometimes what was done to it since. Unlike the sparkle it is not drawn into the picture, and unlike SynthID it is not hidden in the pixels — it rides along in the file's metadata.
That makes it the most fragile of the three and the easiest to check. Re-saving in an editor that does not understand it, or uploading to a platform that strips metadata, can drop it entirely. So an image with no Content Credentials is not evidence of anything, while an image with them is reasonably strong evidence of where it came from.
What survives which edit
This is the practical question, and the honest answer is "it depends on the edit". Roughly:
| What you do to the image | Visible sparkle | SynthID | Content Credentials |
|---|---|---|---|
| Crop the corner off | Gone | Designed to survive | Depends on the editor |
| Resize smaller | Still there, smaller | Designed to survive | Depends on the editor |
| Re-save as JPEG | Still there, softer | Designed to survive | Often dropped |
| Screenshot it | Still there | Often survives | Gone — a screenshot is a new file |
| Heavy compression | Still there, blurred | Weakens | Usually gone |
| Upload to most social platforms | Still there | Often survives | Frequently stripped |
| Remove with Imaginoa | Gone | Untouched | Untouched |
Note the last row. Imaginoa reverses the blend on the visible mark and does nothing else. It does not alter metadata and makes no attempt to interfere with SynthID — that is a deliberate line, not an oversight.
How to check an image yourself
You do not have to take anyone's word for what is in a file:
- Content Credentials: drop the file into contentcredentials.org/verify. It will show the signed history if there is one.
- SynthID: there is no public tool you can run on an arbitrary file. Detection is offered through Google's own surfaces — see the SynthID page. If a site claims to detect or strip SynthID for you, be sceptical.
- The visible sparkle: your eyes, and a zoom into the corners.
Three myths worth killing
- "Removing the sparkle makes it undetectable." It does not. The visible mark and the invisible one are separate things, and only the first one comes off.
- "If there is no watermark, it is not AI." Plenty of AI images never carried a visible mark in the first place, and plenty of real photographs have logos on them. The absence of a mark tells you almost nothing.
- "SynthID is unbreakable." Google describes it as resistant to common edits, not indestructible, and heavy degradation weakens it. That is an argument for honest labelling, not for trying to defeat it.
What this means if you publish
If you post AI images anywhere people might take them for photographs, the sensible default is to say so — in a caption, a credit line, or wherever your audience will actually see it. Regulations are moving the same way: Article 50 of the EU AI Act sets transparency obligations around synthetic content, and the major platforms have their own labelling rules on top.
A corner sparkle was never what made that obligation real. Cleaning up a thumbnail is a design decision; telling your audience what they are looking at is a separate one, and the second matters more than the first.
FAQ
Does Imaginoa remove SynthID?
No. It only removes the visible sparkle.
Can SynthID be seen?
No. It is invisible to people and is meant to be read by detection tools.
Does cropping remove SynthID?
SynthID is designed to withstand common edits such as cropping and compression.
Is it okay to remove the visible watermark?
Only on images you created or have permission to edit, and be open about AI use where it is expected.
Is Content Credentials the same as SynthID?
No. Content Credentials are a signed record in the file's metadata that can be stripped by re-saving. SynthID is hidden inside the pixels themselves and is built to survive ordinary edits.
Does Imaginoa change the image metadata?
No. It reverses the visible mark and leaves everything else alone, including any Content Credentials in the file.
Can I check whether an image has SynthID?
Not with a general public tool. Detection is offered through Google's own surfaces. Treat any site claiming to detect or strip it with suspicion.
If I crop the corner off, is the image clean?
The visible sparkle is gone, but SynthID is designed to survive cropping, so the image is not untraceable — and you have lost part of your picture for nothing.