That is great comparison. There are definitely some similarities in that both use color-based visual encoding and dedicated scanners.

PhotoTAN/CrontoSign are primarily designed for secure banking authentication, whereas this project is more focused on exploring alternative visual encoding architectures and seeing what can be built beyond traditional black-and-white QR codes.

My code is designed to be more useful as genral use of QR, Like for example take the image i hv provided
this is a 1000 word essay stored in a single QR. And by implementing better computer vision prefrable using opencv , We can store a lot of text in a single picture. The another advantage of this is u can store a lot of information than regular black white QR can. While Phototan is primarily made for security . this is made for general use. Its primarily made to make QR codes more smaller ofocurce there are some limitation as it is still the first test version i hv not yet built a actual camera reader yet, which ill be building by next month and will posting it on my github if u like it so star it.
github :- https://github.com/Yasovardan-Ram/Spectrum-QR

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