camera - QR code-like alternative with extremely low error rate and ability to read bent codes -


i'm trying find alternative qr codes (i'd willing accept entirely novel solution , implement myself) meets specifications.

  • first, codes end on thin pipes, , need readable around cylinder. advantage effect on image wrapping around cylinder easy express geometrically, , codes never placed on irregular shape.
  • second, read accuracy must high, read mistake extremely costly. if means larger codes more redundancy better error correction, it.
  • third, ability read average smartphone camera few inches out.
  • fourth, storage space of around half kilobyte per code.

do know of such code?

the data matrix rectangular extension (dmre) improves upon standard set of rectangular data matrix symbol sizes in algorithmically compatible manner, increasing range of suitable applications no real downsides.

reliable cylindrical marking primary use case.

regardless of symbology unable approach sufficient data density achieve 0.5kb of binary data in single compact, narrow symbol scanned using standard camera phone. however, 2d symbologies (dmre included) support feature called structured append allows chaining of multiple symbols can scanned in order produce single read when components accounted for.

if data encoded known highly structured (e.g. numeric or alphanumeric) internal encoding process of data matrix more optimised general binary data. example, largest dmre symbol (26×64) provide 236 numeric characters, ~175 alphanumeric characters , 116 bytes.

if default error recovery rate insufficient including checksum in data may appropriate.

dmre has been voted accepted iso/iec project , become international standard enjoying broad hardware , software support in due course.

another option may investigate pdf417 has broader range of symbols sizes, data density less data matrix.

dmre references: aim specification , explanatory notes.


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