What you need
Choose one authorised JPEG, PNG, or WebP image up to 20 MB and 12 million decoded pixels. Animated frames are not processed.
Image Tools / Local studio
Image Threshold Maker
Convert weighted still-image luminance to black or white at a selected cutoff, preserve alpha, and process entirely in browser.
Runs locallyNo image upload to Nirmion
Step 1 / Source
Choose one image
Drop your image here
Or browse for a JPEG, PNG, or WebP image that you own or are authorised to edit.
One file · up to 20 MB · maximum 50 megapixelsStep 2 / Output
Image Threshold Maker controls
Select 0 to 255; pixels at or above the cutoff become white and lower-luminance pixels become black. Pixel processing stays in this browser tab.
Create the threshold imageThe source file is not overwritten. Export creates a separate threshold image.
Keep this page open until the download begins.01No server upload
The selected image is decoded and re-encoded inside this browser tab.
02Working copy released
After download, the preview URL, decoded bitmap, canvas, and selected source reference are cleared.
03Your download remains
Nirmion cannot remove the finished file from your device or browser download history.
Workflow guide
A controlled image threshold maker workflow
Weighted luminance is compared with the selected 0-to-255 threshold; each visible pixel becomes either black or white. Review the result against the intended display rather than treating the setting as an objective correction.Social-ready choices
Prepare a high-contrast review copy of a signature or line drawing while checking thin marks for disappearance.
What you receive
Download a separate threshold image. Dimensions remain unchanged unless the selected encoder handles the source differently.
Decision guide
What image threshold maker changes
Weighted luminance is compared with the selected 0-to-255 threshold; each visible pixel becomes either black or white.
A single global threshold does not deskew, denoise, segment subjects, recognize text, or guarantee a scan suitable for evidence. Browser-local processing avoids a Nirmion file upload, but it does not remove copies already stored elsewhere.
W3C Filter Effects Module Level 1Useful image threshold maker checks
- Prepare a high-contrast review copy of a signature or line drawing while checking thin marks for disappearance.
- Create a reversible review copy while preserving the original image for comparison or later editing.
- Prepare a consistent derivative for an authorised design, publishing, or archival workflow.
Good to know
Important image boundaries
- Why might a PNG not become smaller?
- PNG is lossless and browsers do not expose a quality control for it. Choose WebP or JPEG when reducing file size matters more than exact lossless pixels.
- Are animated images supported?
- No. The workspace accepts still JPEG, PNG, and WebP files. Re-encoding an animated source would otherwise keep only one frame.
- What does clearing the file mean?
- Because processing is local, there is no Nirmion server copy to delete. The tab releases its working references after success; your downloaded output remains on your device.
Questions answered
Frequently asked questions
Does Image Threshold Maker upload my image?
No. For supported JPEG, PNG, and WebP inputs, decoding, image threshold maker, canvas rendering, and export run in your current browser tab. Nirmion does not send the selected image to its API for this workflow. The downloaded file is a new derivative; your original device file remains unchanged and should be retained when future editing or verification matters.
What does Image Threshold Maker change?
Weighted luminance is compared with the selected 0-to-255 threshold; each visible pixel becomes either black or white. The operation is applied to decoded RGB pixels while the alpha channel is preserved. It does not resize the canvas, recover clipped source detail, identify subjects, or infer a professionally correct look. Inspect representative shadows, midtones, highlights, edges, text, and transparent areas before relying on the exported copy.
What are the limits of Image Threshold Maker?
A single global threshold does not deskew, denoise, segment subjects, recognize text, or guarantee a scan suitable for evidence. The workspace accepts one supported still image up to 20 MB and limits pixel-intensive effects to 12 million decoded pixels for predictable browser memory use. Output also depends on the browser encoder and selected format. Animated images, raw camera development, colour-profile calibration, and batch processing are outside this tool's scope.