A contour can support image analysis, but its pixel area is not automatically a physical measurement. Camera geometry and scale remain part of the problem.
OpenCV documents contours as image boundaries that can support shape and area calculations. OpenCV — contours.
Establish the reference
For a flat-component study, identify the capture geometry and suitable calibration basis. A size comparison between unrelated photographs can otherwise reflect distance from the camera rather than product variation.
Keep the claim narrow
Review boundary errors and perspective effects before interpreting the result. A two-dimensional image area also does not establish three-dimensional volume. Preserve the measurement method and its uncertainty instead of presenting a pixel-derived number as an exact product specification.
Source reviewed 25 October 2026. Interpretation and original diagrams: PLUSHIP / Qunhe. Examples are illustrative.
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Hyperparameter Search Needs a Separate Performance Estimate