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Nanoalpha

Nanoalpha: Extract transparent PNG sprites from AI-generated images. Upload the same render on a light and dark background — processing runs entirely in your br.

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MarkoUnity/NanoAlphaMIT★ 10

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What's next with Nanoalpha?

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Use it free

Open the official tool or demo — no account needed.

Free

Self-host it

Run the open-source version on your own infrastructure.

Open

What is Nanoalpha?

Static browser app for extracting transparent PNG sprites from AI-generated images. NanoAlpha removes backgrounds from a **single source image** and exports a clean RGBA PNG. You can also add an optional second image with a contrasting background for higher-quality alpha recovery. All processing runs locally in your browser — no uploads, no build step, no dependencies. - **Single-image matting** — remove a solid or near-solid background from one render using OKLab color distance, border flood fill, and edge alpha estimation - **Optional two-image matting** — add a contrast plate (same dimensions, different background) for difference-based alpha recovery - **Simple and Advanced controls** — three sliders for everyday tuning, or full access to probe size, tolerance, matte width, decontamination, and dual-image options - **Auto background detection** — samples th Source: MarkoUnity/NanoAlpha (https://github.com/MarkoUnity/NanoAlpha)

How it works

Repository: MarkoUnity/NanoAlpha - **Single-image matting** — remove a solid or near-solid background from one render using OKLab color distance, border flood fill, and edge alpha estimation - **Optional two-image matting** — add a contrast plate (same dimensions, different background) for difference-based alpha recovery - **Simple

How to use it

  1. 1Upload the AI-generated image that contains the sprite sheet.
  2. 2Let the tool detect the transparent sprite regions by scanning the alpha channel.
  3. 3Adjust the detection threshold if stray pixels are included or sprites are missed.
  4. 4Preview the extracted sprites to confirm each element is separated cleanly.
  5. 5Download the sprites as individual transparent PNGs for use in your project.

What it can do

  • Generation
  • Preview

Use cases

Assumptions and limitations

Assumptions

  • source: https://github.com/MarkoUnity/NanoAlpha
  • license: MIT — free to use, modify, and distribute
  • privacy: Runs locally in your browser — no data leaves your device
  • stars: 10+ stars on GitHub

Limitations

  • Source and contrast images must have the same dimensions for two-image matting.
  • Use **Ctrl + scroll** over the previews to zoom. Scrolling stays synchronized across source and output.
  • Simple sliders drive the underlying Advanced parameters; switching modes does not lose your settings.
  • Processing runs locally in your browser. Images are not sent anywhere.

Understanding the result

Static browser app for extracting transparent PNG sprites from AI-generated images.

Tool details

  • Clearly flagged when a network request is needed.
  • No account, no sign-up, and no tracking of your content.
  • Powered by NanoAlpha (MIT).
Built with
NanoAlpha (MarkoUnity/NanoAlpha)
License
MIT
Runs locally
No — requires a network request
Verification
Not yet verified
Input
Text Input
Output
Image, Generated Output
Open-source source & license

Built with MarkoUnity/NanoAlpha. OpenToolVault provides the discovery and browser interface while crediting the original project maintainers.

Built with
NanoAlpha
License
MIT
View source on GitHub

Open-source project

License: MITSource: this projectOfficial site

OpenToolVault is an independent directory. We are not affiliated with or endorsed by this project.

References

Frequently asked

What is Nanoalpha?

Static browser app for extracting transparent PNG sprites from AI-generated images. NanoAlpha removes backgrounds from a **single source image** and exports a clean RGBA PNG. You can also add an optional second image with a contrasting background for higher-quality alpha recovery. All processing run It is available on GitHub at MarkoUnity/NanoAlpha.

Is Nanoalpha free to use?

Yes — Nanoalpha is open-source software. You can use it freely, and the source code is available at https://github.com/MarkoUnity/NanoAlpha.

What are its key capabilities?

- **Single-image matting** — remove a solid or near-solid background from one render using OKLab color distance, border flood fill, and edge alpha estimation - **Optional two-image matting** — add a contrast plate (same dimensions, different background) for difference-based alpha recovery - **Simple and Advanced controls** — three sliders for every

Where can I try this tool?

This tool is hosted by its maintainers. Visit the official demo or source repository to use it. (https://github.com/MarkoUnity/NanoAlpha)

How is Nanoalpha licensed?

It is open-source. Check the repository (https://github.com/MarkoUnity/NanoAlpha) for the specific license.

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