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Project TransparantQR
Transparant QR code
Status Completed
Contact cmpxchg
Last Update 2022-04-27


Based on an idea of Zack Freedman twitter link


Make it work with a full-color moving video in the back.

  • Use same large markers
  • Make them a little more transparent (25%)
  • With contrast of the large markers, reader will construct lines along which the blocks are sample
  • Reduce size of blocks to about 1/9th of original blocksize
  • Make everything around the block transparent
  • Result: working transparent QR code!

Does not work on all readers, zbarimg fails on the PNG, but could be due to PNG alpha channel interpreted in the wrong way.

Resulting code distribution

It is a patch to GPL code, so modified source must be published. For convenience, patch file is encoded in QR as well. Commit message redacted and reduced, xz compression, and it fits!

Sourcecode patch to libqrencode: (xz compressed patchfile)


Additional changes: Reduce location_ishiconstrast() remove the line 6 tests for even more area, seems to be allowed on most phone-based QR readers.

User interface

qrencode -o out.png -T insertyoururlorotherdatahere

will output a PNG32 file out.png


building yourself: git clone and follow same instructions as original

Sample image

Below transparent, PNG32 format file can be overlayed on any graphic and redirects to