Adding logo to the center of a QR Code

[markaspirenet]

I have the JAR running on a ColdFusion/Lucee server and it's working perfectly. I'd like to add a logo or some text to the center of the QR, could anybody help me understand what parameter I would pass when I generate the code? Thanks

[srowen]

That would not have anything to do with the library. But once you generate the image, you can use any Java-based library to manipulate the image further

[markaspirenet]

Is there a particular amount of space in the center of the QR that is not impacts with an image? I presumed that if you add an image that it would need to adapt to take the image into consideration

[srowen]

It depends on the EC level and size of the QR code. From level L to H, the error tolerance is 7 to 30%. You can figure that half your modules will be corrupted by the image. So you might use that to figure out an absolute maximum of the image you can corrupt. I personally would not do this at all. But if you do, keep it very small and in the center.

[markaspirenet]

At the moment it's set to H, I'm not clear on how much impact setting it to L would have, the image is 400x400. I don't have a lot of knowledge of how they work, I presumed the code would adjust as necessary or have a dead spot in the middle, but if that's not the case and it impacts the chances of a successful scan, then I agree, I should stay clear of it, it's not that important to me, it was just a nice to have. Thanks for the quick replies, much appreciated

[oehhar]

It is not as easy as this. Don't damage any finding patterns (the small fix pyramids). If you want to put it into the center, choose a size which does not have finders in the center.
Otherwise, the QR-code is graded F by ISO/IEC15415 and considered as invalid.
In addition, take care that the 4 big pyramids at the corners require 4 modules of quiet zone.

[markaspirenet]

I'm already scared away from touching it, as there is no mechanism to protect it's integratory 100%, I'm just going to leave it out