Image metadata guide

How to Remove NovelAI Metadata and Hidden PNG Data

Clean supported NovelAI stealth_pngcomp data as well as ordinary PNG metadata in your browser. Learn how to inspect the original and recheck the exported copy.

By Remove AI Label · Updated October 2, 2026

Open the free metadata remover

Check both ordinary and hidden metadata

NovelAI PNGs may contain readable text fields and an Alpha-channel payload. Deleting EXIF or PNG text alone can leave supported stealth_pngcomp data intact. Our tool checks ordinary file blocks and this specific hidden-data format.

Visible crop from the existing NovelAI example
Visible picture
Enhanced Alpha low-bit heatmap from the same example
Alpha-channel differences, enhanced

These crops illustrate the hidden layer, not the result of cleaning your image. The Alpha-channel visual explanation covers how the storage format works.

Clean a NovelAI PNG step by step

  1. Save the original PNG. Use a separate delivery copy so you can retain its generation records.
  2. Add it to the image metadata remover. Click the file status badge and review the detected Alpha hidden-data signal and available fields.
  3. Select Remove metadata. When a supported hidden payload is decoded, the tool rebuilds Alpha least-significant bits, exports a PNG and checks that the same hidden marker is no longer readable. Ordinary PNG metadata is omitted during that export.
  4. Download and inspect the result. Clear the workspace and add the saved result. Check both ordinary metadata details and the supported hidden-data signal.

What changes during hidden-data removal?

This cleanup is different from removing a file header. The Alpha carrier is modified: the low-bit cleanup changes affected Alpha values by at most one level, preserving fully transparent and fully opaque endpoints. The image is exported through the browser canvas at its original dimensions.

Because canvas decoding and export can also affect color handling and pixels, this path is not a byte-for-byte or pixel-identical preservation promise. Compare the downloaded file with the original, especially for semitransparent artwork. Cropping is a separate operation and can change dimensions.

Verify the downloaded copy

  • Look for the absence of the previously detected stealth_pngcomp signal.
  • Check that original prompts and parameters no longer appear in the supported metadata report.
  • Review the saved image visually, including transparent edges.
  • For an independent check, use the extraction tools in NovelAI's public image-metadata project on the downloaded copy.

Our built-in verification checks the supported hidden marker. It does not verify a NovelAI signature, examine every steganography scheme or establish that an image is undetectable as AI-generated.

Why might no hidden data be found?

The file may have no supported payload, may have been resized or re-encoded, or may use a variant this tool does not decode. A clean report describes what this scanner can read; it does not establish the image's origin.

Should I convert it to JPEG?

JPEG does not preserve a PNG Alpha channel, but conversion also loses transparency and uses lossy compression. Use the PNG cleanup path when you want a PNG delivery copy and inspect its output.

Does this also remove SynthID?

No. Support for NovelAI's specific Alpha payload does not imply support for unrelated pixel watermark systems.