The Mathematics of Barcodes: How EAN-13 and Code 128 Work
Explore the internal logic of barcodes. Understand check digits, parity patterns, and encoding algorithms for EAN-13 and Code 128 standards.
📋 Inhaltsverzeichnis
In the world of logistics and retail, barcodes are the silent workhorses that move trillions of dollars in goods every year. To the casual observer, they are merely a series of black and white lines. However, to a developer or an engineer, they are a masterpiece of error-correction mathematics and efficient data encoding. This guide dives deep into the technical specifications of two of the most popular 1D barcode standards: EAN-13 and Code 128.
Anatomy of a 1D Barcode
A 1D barcode doesn’t represent an image; it represents a sequence of bits. The "bars" are 1s and the "spaces" are 0s. The width of these bars/spaces is measured in "modules"—the smallest unit of a barcode.
A standard 1D barcode consists of:
- Quiet Zones: Clear space on both ends to help scanners identify the start and end of the code.
2. Start and Stop Patterns: Specific sequences that indicate the direction of the scan.
3. Data Characters: The encoded payload.
4. Check Digit: A mathematical verification digit to ensure the scan was accurate.
Karuvigal Team
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