Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

How do you get text inside of QR codes? I know i seen this more then once but here is an image from the latest example. UCM are the initials of that company.

enter image description here

share|improve this question

QR codes, along with most other 2-D barcodes, are able to cope with damage to the barcode and still be able to reconstruct the data. There are a couple standard levels; L, M, Q, H, which adjust this error correcting capability.

The text there doesn't cover enough of the barcode to render the data unrecoverable, but it does make it more sensitive. You can demonstrate this yourself by taking some QR code and drawing a line through it. If it didn't cover too much of the data region, a scanner will be unphased by it. IF the non-coding regions or the registration marks are covered up, however, there will likely be problems.

share|improve this answer

Interesting, that is:


Here's what I used for decoding:

And ou can have more fun here:

Oops .. I did not understand the question properly, once I read your replies I understood what you wanted to do .. I suddenly saw that "UCM" in the barcode. Was a very funny moment :)

btw, is this what you want? (This barcode decodes to the URL to this page)

This barcode decodes to the URL to this page

This is all about error correction, make the Barcode with as much error correction info as possible (30%), then hack away at the image and insert whatever logo you want, as long as it leaves enougth information for decoding to happen you can get your logo in there.

Hope this is what you were looking for.

Same thing in other Fonts...


share|improve this answer
What does that thing have to do with the question? – Wuffers Mar 12 '11 at 2:21
Alright but the question was about encoding letters in the picture. I had no problem decoding it – acidzombie24 Mar 12 '11 at 2:21
btw, you might want to read up on there might be regions you can't mess with. I don't know if there are or not, but definately worth the read before attempting anything production ready. – chkdsk Mar 12 '11 at 3:00
Hmm... Your pic look like regular text and theirs looks like its actually generated and every block is a large pixel. I'll +1 cause it is A way to do it. – acidzombie24 Mar 12 '11 at 4:28
@acidzombie24: That is just a matter of finding the right font, or making the right font ourself. See another font being used above, much better, tho not the same. I think this is the core principal behind whatever method you use. After this you need to find a good font :-) – chkdsk Mar 12 '11 at 9:13

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.