rqr

react-qr-reader

React component for reading QR codes from webcam.

Showing:

Popularity

Downloads/wk

34.9K

GitHub Stars

805

Maintenance

Last Commit

3yrs ago

Contributors

15

Package

Dependencies

3

License

MIT

Type Definitions

Tree-Shakeable

No?

Reviews

Average Rating

2.0/51
Read All Reviews
smox

Top Feedback

2Great Documentation
2Buggy
1Easy to Use
1Performant

Readme

npm version

Introduction

A React component for reading QR codes from the webcam. It uses the WebRTC standards for reading webcam data and jsQR is used for detecting QR codes in that data. To optimise the speed and experience, a web-worker is used to offload the heavy QR code algorithm on a separate process. The web worker is inlined and loaded on creation of the component.

Demo

https://jodusnodus.github.io/react-qr-reader

Known Issues

  • Server side rendering won't work so only require the component when rendering in a browser environment.
  • Due to browser implementations the camera can only be accessed over https or localhost.
  • In Firefox a prompt will be shown to the user asking which camera to use, so facingMode will not affect it.
  • On IOS 11 it is only supported on Safari and not on Chrome or Firefox due to Apple making the API not available to 3rd party browsers.

Install

npm install --save react-qr-reader

Example

import React, { Component } from 'react'
import QrReader from 'react-qr-reader'

class Test extends Component {
  state = {
    result: 'No result'
  }

  handleScan = data => {
    if (data) {
      this.setState({
        result: data
      })
    }
  }
  handleError = err => {
    console.error(err)
  }
  render() {
    return (
      <div>
        <QrReader
          delay={300}
          onError={this.handleError}
          onScan={this.handleScan}
          style={{ width: '100%' }}
        />
        <p>{this.state.result}</p>
      </div>
    )
  }
}

Props

Events

PropArgumentDescription
onScanresultScan event handler. Called every scan with the decoded value or null if no QR code was found.
onErrorErrorCalled when an error occurs.
onLoadobjectCalled when the component is ready for use. Object properties are mirrorVideo: boolean, streamLabel: string
onImageLoadimg onLoad eventCalled when the image in legacyMode is loaded.

Options

PropTypeDefaultDescription
delaynumber or false500The delay between scans in milliseconds. To disable the interval pass in false.
facingModeuser or environmentenvironmentSpecify which camera should be used (if available).
resolutionnumber600The resolution of the video (or image in legacyMode). Larger resolution will increase the accuracy but it will also slow down the processing time.
stylea valid React stylenoneStyling for the container element. Warning The preview will always keep its 1:1 aspect ratio.
classNamestringnoneClassName for the container element.
showViewFinderbooleantrueShow or hide the build in view finder. See demo
constraintsobjectnullUse custom camera constraints that the override default behavior. MediaTrackConstraints
legacyModebooleanfalseIf the device does not allow camera access (e.g. IOS Browsers, Safari) you can enable legacyMode to allow the user to take a picture (On a mobile device) or use an existing one. To trigger the image dialog just call the method openImageDialog from the parent component. Warning You must call the method from a user action (eg. click event on some element).

Dev

Install dependencies

npm install

Build

npm run build

Demo

npm run storybook

Linting

npm run lint

Tested platforms

  • Chrome macOs & Android
  • Firefox macOs & Android
  • Safari macOs & IOS

License

The MIT License (MIT)

Copyright (c) 2018 Thomas Billiet

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Rate & Review

Great Documentation2
Easy to Use1
Performant1
Highly Customizable0
Bleeding Edge0
Responsive Maintainers0
Poor Documentation0
Hard to Use0
Slow0
Buggy2
Abandoned0
Unwelcoming Community0
100
Michael BrunnerLengenfeld5 Ratings1 Review
Hello my name is Michael! I'm 32 Years old and I am working as a Linux IT Administrator. This GitHub Profile is for my Hobby projects.
7 months ago
Great Documentation
Easy to Use
Performant
Buggy

I've used this app for a small progressive web app. The reason I tried this library because it looked very well documented and very professional. Sadly, it is not working in mobile browser. This is the reason why I dumped it.


0
dvthust1 Rating0 Reviews
6 months ago
Great Documentation
Eduardo RochaRecife, Brasil1 Rating0 Reviews
6 months ago
Buggy