barcode scanners

 comparision of various barcode scanner scripts.  by dynamsoft

opensource

https://zxing.org/w/decode.jspx available at https://github.com/zxing/zxing

very popular opensource one mentioned to compare in dynamsoft youtube video.

extension of zxing https://serratus.github.io/quaggaJS/

https://github.com/khanamiryan/php-qrcode-detector-decoder - from Zxing

https://scanapp.org/html5-qrcode-docs/docs/apis - by google ML employee

https://www.geeksforgeeks.org/create-a-qr-code-scanner-or-reader-in-html-css-javascript/

webqr.com

paid ones

more advanced

scandit

https://www.dynamsoft.com/

750 scans per minute - folded, curved, erased, low light, shadow, side scaning  etc..