Translation

Combined 1D and 2D Barcodes

The article describes a project to create a hybrid barcode that combines a traditional 1D UPC barcode with a 2D QR code, allowing scanners to read the numeric code up close while QR readers can decode the full pattern from a distance.

Background

- The author Terence Eden is a UK-based technologist who often experiments with quirky digital/physical hybrid projects; this is a personal blog post, not a news article. - UPC (Universal Product Code) is the traditional linear (1D) barcode of vertical black bars found on retail products since the 1970s. QR codes are two-dimensional (2D) square matrix codes that store much more data and are scanned by smartphone cameras. - Retailers are gradually shifting from UPC barcodes (scanned by laser) to QR codes (scanned by cameras) because QR codes can hold URLs, product details, and expiry dates — but many legacy point-of-sale systems still rely on UPC. - The author's experiment: design a single image that works as a QR code when scanned normally, but as a UPC barcode when the camera is held very close (so the QR positioning squares fall outside the frame). This is a creative hack, not an existing standard — it explores backwards compatibility between old and new scanning technology.

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Combined 1D and 2D Barcodes

Background

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