Коррекция ошибок в Micro QR и rMQR
How error correction differs in compact variants: Micro QR (L/M/Q) and rMQR (M/H only). Capacity implications.
Error Correction in Micro QR and rMQR
Compact QR code variants — Micro QR and rMQR — have reduced error correction options compared to standard QR codes. Understanding these limitations is critical for space-constrained applications.
Micro QR Error Correction
Micro QR codes offer limited EC levels depending on the version:
| Version | Available EC | Max Recovery |
|---|---|---|
| M1 | Error detection only | 0% (detect only) |
| M2 | L, M | 7% or 15% |
| M3 | L, M, Q | 7%, 15%, or 25% |
| M4 | L, M, Q | 7%, 15%, or 25% |
Notable: EC Level H (30%) is not available in any Micro QR version. Version M1 can only detect errors, not correct them.
rMQR Error Correction
Rectangular Micro QR codes support only two EC levels:
| EC Level | Recovery Rate |
|---|---|
| M | ~15% |
| H | ~30% |
Levels L and Q are not available for rMQR. This limits flexibility — you must choose between moderate (M) and high (H) protection.
Capacity Impact
The reduced symbol size of compact variants means EC has a proportionally larger impact on capacity. For Micro QR M4 at EC-L, maximum byte capacity is 21 characters. At EC-Q, it drops to 11 characters — a 48% reduction.
For rMQR, the rectangular aspect ratio provides more total modules than a Micro QR of equivalent height, partially offsetting the EC overhead.
Practical Recommendations
- For critical data: Use standard QR codes instead of compact variants
- Micro QR M1: Only use for extremely simple numeric data where detection (not correction) suffices
- Micro QR M3/M4 at EC-Q: Good balance for industrial labels
- rMQR at EC-H: Provides robust correction in a narrow form factor
Scanner Compatibility Note
Not all scanners support Micro QR or rMQR error correction fully. Some may decode correctly at EC-L but fail to apply full error correction at higher levels. Always test with your target scanning hardware before deploying in critical applications.
Key Takeaways
- Micro QR lacks EC Level H; Version M1 supports detection only
- rMQR supports only M and H error correction levels
- EC has a proportionally larger capacity impact on compact variants
- Standard QR codes remain the best choice for critical or high-damage scenarios
- Scanner support for compact variant EC is inconsistent