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.
đź“‹ ĂŤndice
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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