TrueFootprint 作成者: nguyenan5208

Product photographs often hide a simple question: how big is this, really?
TrueFootprint gives a known dimension a visual frame of reference.

Import a PNG, JPEG or WebP, mark the endpoints of a dimension and enter its length in millimetres. Compare measured images side by side with a bank-card rectangle, an A4 sheet or your own reference rectangle. Use fit-to-view mode for an overview, or calibrate your screen with a real bank card for a physical 1:1 view of the marked dimension.

You can also right-click a fully visible webpage image and choose Measure this image. The extension takes a temporary screenshot after that explicit action, crops the image rectangle and retains only that crop. Clipped images and images inside frames are rejected; import a file instead.

Important: only the marked dimension is calibrated. Perspective and image distortion can invalidate other dimensions. TrueFootprint does not infer depth, remove image backgrounds or certify precise physical measurements. Recalibrate after changing monitor, display scaling or browser zoom.

Collections hold up to 12 images. Imports are limited to 10 MB, 12 megapixels and a 12,000-pixel edge. Stored images are resized to a maximum 1600-pixel edge. Export and restore JSON backups. Everything stays in local extension storage: no account, analytics, cloud sync or external asset service. Private-window captures are ignored.