Project - Stage 0.2 - Background Learning

Previous Reading

Project Selection

Some Resources 

- Resources list from the author

• https://en.wikipedia.org/wiki/QR_code : general information about QR codes, to get started
• https://github.com/zxing/zxing : this is a very popular encoder+decoder project written in Java that supports many types of codes, not just QR codes. The image binarization and error correction are almost direct ports of zxing's implementation
• https://en.wikiversity.org/wiki/Reed%E2%80%93Solomon_codes_for_coders : a nice walkthrough of how QR codes work
• https://github.com/nurse/nkf : a Kanji converter used to implement the Shift JIS decoder
• https://encoding.spec.whatwg.org/ : the reference used to implement the Big5, EUC-KR and GB18030 decoders
• https://ftp.unicode.org/Public/MAPPINGS/ISO8859/ : the reference conversion tables for the ISO-8859-XX decoders
• https://www.unicode.org/Public/MAPPINGS/VENDORS/MICSFT/ : the reference conversion tables for the CPXXX decoders

 - Other resource I read in Chinese 

• https://coolshell.cn/articles/10590.html : QR code generation details and principles

 

What I have learned before I make a plan for project optimize

https://coolshell.cn/articles/10590.html

The picture above describes the structure of the QR code clearly. Decoding QR code can be easily divided into following steps:

1. - Unmask
2. - Decide Encode
3. - Decide Length
4. - Decoding into binary list
5. - Translate binary to characters, numbers and so on