Nirmion
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Image Tools / Local studio

Image Pixel Run Length Report

Measure maximal horizontal and vertical runs of exactly equal decoded RGBA tuples, including transparent values.

Runs locallyNo image upload to Nirmion

Step 1 / Source

Choose one image

JPEG · PNG · WebP · 20 MB

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 megapixels

Step 2 / Output

Image Pixel Run Length Report settings

This analysis uses one documented method so repeated runs on the same decoded pixels remain comparable.

Prepare the pixel-run-length JSON reportThe source is not overwritten. Analysis produces a separate pixel-run-length 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 pixel run length report with an inspectable review path

Each row and column is scanned into maximal consecutive runs whose four decoded channel bytes match exactly; count, mean, and longest run are returned. Compare the result with the untouched source before using it downstream.
A

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.

B

Social-ready choices

Compare flat graphics with noisy or dithered exports while recognizing that visually similar colors may still break an exact run.

C

What you receive

Review and download a separate pixel-run-length JSON report; the original file on your device remains unchanged.

Decision guide

What image pixel run length report measures or changes

Each row and column is scanned into maximal consecutive runs whose four decoded channel bytes match exactly; count, mean, and longest run are returned.

Exact runs are not perceptual regions, compression runs, connected components, line detection, texture quality, or evidence of efficient encoding. Browser-local processing avoids a Nirmion file upload, but it cannot remove copies stored elsewhere.

MDN Canvas pixel manipulation

Useful checks for image pixel run length report

  1. Compare flat graphics with noisy or dithered exports while recognizing that visually similar colors may still break an exact run.
  2. Create a bounded review result while retaining the original for comparison, correction, or a different method.
  3. 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 Pixel Run Length 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 Pixel Run Length Report work?

Each row and column is scanned into maximal consecutive runs whose four decoded channel bytes match exactly; count, mean, and longest run are returned. Every decoded RGBA tuple participates, including transparent pixels and their stored RGB bytes, because equality requires all four channels. 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 Pixel Run Length Report?

Exact runs are not perceptual regions, compression runs, connected components, line detection, texture quality, or evidence of efficient encoding. 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.