Hidden Pattern Image Viewer
Use a local high-pass difference view as a visual inspection aid; a visible pattern is not proof of a watermark.
A QUICK WALKTHROUGH
How to use this tool
- Choose one JPEG, PNG, or WebP image up to 20 MB and 40 megapixels.
- Adjust blur radius, gain, and grayscale mode, then render the difference view.
- Inspect or download the processed PNG; interpret patterns cautiously.
What the filter does
The viewer subtracts a blurred copy from browser-decoded pixels, multiplies the residual by the chosen gain, and displays it around mid-gray. This can emphasize edges, texture, ringing, sensor noise, edits, and some repeated low-contrast patterns.
What it cannot prove
A pattern in the output is not proof of a watermark, ownership, manipulation, or a particular embedding method. Proprietary, encrypted, transform-domain, or robust watermarks may remain invisible.
Local resource boundary
Supported files stay in the browser. Input is capped at 20 MB and 40 MP; analysis is downsampled to at most 4 MP and downloaded as a new PNG without source metadata.
GOOD TO KNOW
Common questions
Does this detect every blind watermark?
No. It is a generic difference-enhancement view, not a detector for a named watermark system.
Why do normal edges appear?
High-pass filtering emphasizes any local change, including ordinary detail and compression artifacts.
Is the original image uploaded?
No. Decoding, filtering, preview, and download happen in the current browser.