BrushCue Tool
Apply Lightness Threshold to Image Online
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What you can expect
Applies a threshold to the OkLab L (lightness) component, analogous to how Color Threshold operates on individual RGB channels. This tool converts continuous tonal values into hard transitions, producing a stark, high-contrast, etching-like effect that emphasizes form and structure.
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Read more about Lightness Threshold
Frequently asked questions
- How to apply a lightness threshold to an image?
- Select your file and set the threshold value — pixels with lightness above the threshold become white, below become black.
- What does Lightness Threshold create?
- It splits pixels into pure black or white based on perceptual lightness, producing a stark etching or linocut-like effect.
- Is this like Photoshop's Threshold adjustment?
- Yes — both split an image into pure black or white based on a luminance cutoff. This tool uses perceptual lightness from OkLab color space for more accurate tonal results.
- What file formats can I export?
- You can export as PNG, JPEG, WebP, TIFF, BMP, or HEIC.
- Is this tool free to use?
- Yes — completely free, no account needed. Your images are processed entirely in your browser and never uploaded to a server. Downloads have no watermarks.
For developers
Use Lightness Threshold from Python
Open the Jupyter notebook example to see how to run this tool from the BrushCue Python API, inspect the processing steps, and adapt the workflow for scripts or batch image jobs.
View Python notebookBuild your own
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