What is a Level-H QR Code?

In the digital and connected era for pets, a malfunctioning QR Code can cost the recovery of your missing pet. Because of that, we created a connectivity solution that is robust and practical for daily pet wear.

QR codes, unlike traditional barcodes, support a comprehensive error correction feature.

Thanks to Irving Reed and Gustave Solomon’s Reed-Solomon error-correction algorithm, QR codes can still be scanned even if it gets dirty or worn out. 

Just like in any technological advancement, not all QR Codes are the same. Some are advanced in its algorithm. After all, the modern era uses the Reed-Solomon Error Correction algorithm in satellite, space, and wireless communications.

If you want to dig deeper into how the QR code’s error correction feature works, here is its scientific concept.

The Reed-Solomon Error Correction algorithm is a serious algebra that happens in the background when the QR code is created. The original data in the QR code is converted into a polynomial, the number of unique points required to uniquely define that polynomial is determined, and this point set is added back into the QR code so that it then also contains the original data expressed as a polynomial.

If that technical explanation confused you, let's simplify it! It is mathematically adding backup data to the QR code.

There are 4 error correction levels used for QR codes, with each one adding different amounts of backup data depending on how much damage the QR code is expected to suffer in its intended environment, and hence how much error correction may be required.

This way, it will still be scannable even if the QR code experience a scratch, stain, or any damage due to unfavorable physical conditions.

The Reed-Solomon error-correcting algorithm is not new. It is used for technologies such as CDs and DVDs.

This kind of code measures against the communication noise created by artificial satellites and planetary probes. CD and DVD manufacturers use this code to correct data at the byte level and other burst errors.

With a different kind of tear or damage, here are the following error correction levels that a QR code can have. Starting from Level L to Level H.

How to spot these error correction levels?

Level L

This is the lowest level of error correction rate that a QR code can have. QR code software uses this level if the user intends to generate a less dense QR code image.

Level L has the highest error correction rate of approximately seven percent (7%).

Level M

Level M is the middle tier of the error correction level that QR code experts recommend for marketing use. Because of this, marketers can correct their QR codes at a medium level. Level M has the highest error correction rate of approximately fifteen percent (15%).

Level Q

This level is the second to the highest error correction level. This error correction level has the highest error correction rate of approximately twenty-five percent (25%).

Level H

Level H is the highest error correction level that can withstand an extreme level of damage in their QR code. The level Q and H error correction levels are most recommended for industrial and manufacturing companies.

These codes can experience both environmental and man-made conditions that lead to inevitable damages. This level has the highest error correction rate of approximately thirty percent (30%).

By knowing these following levels, you can spot the QR code’s error correction level without the need of running decoding software. You can spot these levels by looking at the following symbols on the codes.

QR Code for Daily Pet Wear

Now that we took you to a short technical introduction of what an error correction of a QR Code is, you now understand that a QR Code you find in a restaurant menu or a phone screen cannot be used for your pet. Its usage conditions are not the same as the daily abuse a pet may cause. Restaurant menus and phone screens don't lie on the concrete floor, it doesn't get stained with food and other liquids.

Pawnec's QR Codes are designed and tested for pets. It's a reliable and secured connectivity that you can count on.