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 Contrast Adjuster
Expand or compress RGB distance from the tonal midpoint with a bounded control, local processing, and a separate image export.
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 Contrast Adjuster controls
Choose a negative value to compress contrast, 0 to preserve it, or a positive value to expand separation around the midpoint. Pixel processing stays in this browser tab.
Create the contrast-adjusted imageThe source file is not overwritten. Export creates a separate contrast-adjusted 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 contrast adjuster workflow
The selected amount applies a midpoint-relative contrast factor, moving channel values away from or toward 128 before clamping. Review the result against the intended display rather than treating the setting as an objective correction.Social-ready choices
Increase separation in a flat product image while checking labels, reflections, and dark materials for lost detail.
What you receive
Download a separate contrast-adjusted image. Dimensions remain unchanged unless the selected encoder handles the source differently.
Decision guide
What image contrast adjuster changes
The selected amount applies a midpoint-relative contrast factor, moving channel values away from or toward 128 before clamping.
Global contrast does not perform local tone mapping, scene recognition, calibrated grading, or recovery of already clipped pixels. Browser-local processing avoids a Nirmion file upload, but it does not remove copies already stored elsewhere.
W3C Filter Effects Module Level 1Useful image contrast adjuster checks
- Increase separation in a flat product image while checking labels, reflections, and dark materials for lost detail.
- 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 Contrast Adjuster upload my image?
No. For supported JPEG, PNG, and WebP inputs, decoding, image contrast adjuster, 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 Contrast Adjuster change?
The selected amount applies a midpoint-relative contrast factor, moving channel values away from or toward 128 before clamping. 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 Contrast Adjuster?
Global contrast does not perform local tone mapping, scene recognition, calibrated grading, or recovery of already clipped pixels. 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.