What you need
Choose one authorised JPEG, PNG, or WebP still image up to 20 MB and 12 million decoded pixels. Animated frames are not processed.
Image Tools / Local studio
Image Transparency Bounds Report
Find the smallest axis-aligned rectangle containing every pixel with alpha above zero and report transparent canvas margins.
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 Transparency Bounds Report settings
This analysis uses one documented method so repeated runs on the same decoded pixels remain comparable.
Prepare the transparency-bounds JSON reportThe source is not overwritten. Analysis produces a separate transparency-bounds JSON report.
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
Use image transparency bounds report with an inspectable review path
The scan records minimum and maximum coordinates where decoded alpha exceeds zero, then derives inclusive bounds, four margins, and canvas-area coverage. Compare the result with the untouched source before using it downstream.Social-ready choices
Inspect whether a transparent product asset carries unintended padding before choosing a separate, reviewed crop operation.
What you receive
Review and download a separate transparency-bounds JSON report; the original file on your device remains unchanged.
Decision guide
What image transparency bounds report measures or changes
The scan records minimum and maximum coordinates where decoded alpha exceeds zero, then derives inclusive bounds, four margins, and canvas-area coverage.
Alpha bounds do not identify subjects, recommend a crop, include invisible RGB, infer optical whitespace, or guarantee safe layout alignment. Browser-local processing avoids a Nirmion file upload, but it cannot remove copies stored elsewhere.
MDN Canvas pixel manipulationUseful checks for image transparency bounds report
- Inspect whether a transparent product asset carries unintended padding before choosing a separate, reviewed crop operation.
- Create a bounded review result while retaining the original for comparison, correction, or a different method.
- Test representative flat areas, gradients, edges, text, transparency, and high-frequency texture before accepting the output.
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 Transparency Bounds Report upload my image?
No. Supported JPEG, PNG, and WebP decoding, pixel inspection, transformation, and export run in your current browser tab. Nirmion does not send the selected image to its API for this workflow. The result is a separate derivative or JSON report, while the original file on your device remains unchanged and should be retained for comparison.
How does Image Transparency Bounds Report work?
The scan records minimum and maximum coordinates where decoded alpha exceeds zero, then derives inclusive bounds, four margins, and canvas-area coverage. Fully transparent samples are excluded from numerical reports, while visual effects preserve source alpha. The method does not infer subjects, restore missing detail, calibrate a display, or develop raw camera data. Compare edges, gradients, text, texture, and transparent areas with the original before relying on the result.
What are the limits of Image Transparency Bounds Report?
Alpha bounds do not identify subjects, recommend a crop, include invisible RGB, infer optical whitespace, or guarantee safe layout alignment. The workspace accepts one supported still image up to 20 MB and caps this pixel-intensive operation at 12 million decoded pixels for predictable browser memory use. Results depend on browser decoding and encoding support. Animation, raw development, ICC calibration, layer editing, and batch processing are outside this tool's verified scope.