In Gemini 3.5, watermark removal does not work correctly when generating images with aspect ratios other than 1:1.

[dwlegend]

[allenk]

Thanks for the report and the sample. I inspected the image, and the watermark on it has been modified from Gemini's original output — the file looks resized / re-compressed: the "diamond" is very faint (only ~15/255 brighter than its background, versus a clean ~50% on a native output), blurred, and sitting at a non-standard position (≈169 px from the right edge instead of the canonical 192). 2752×1536 is also ≈1.79:1, not a clean 16:9 (1.78) — another sign the file was rescaled.

That matters because removal here is mathematically exact reverse alpha blending — it depends on the watermark's original size, position, and intensity. Once an image is resized or re-saved, those no longer match, so auto-detect can't lock on and a fixed-strength removal over/under-shoots.

To be clear: Gemini 3.5 natively produces many aspect ratios (it isn't only 1:1), and the tool handles those original outputs fine. The problem here isn't the aspect ratio — it's that this particular file was altered after it was generated. Best fix: run it on the original, unmodified Gemini output.

If you only have this modified copy and still want to clean it, you'll need to tune the removal intensity (the watermark here is weaker than normal). This GeminiWatermarkTool build doesn't expose an intensity control, but our VeoWatermarkRemover build does — its GUI can edit images and has an Alpha-intensity slider. Grab it from VeoWatermarkRemover Releases, open the image, set a Custom region at (2488, 1252), 96×96, and Alpha intensity ×0.68 — that removes it cleanly on this file.