qrcode-reader

JavaScript QRCode reader for HTML5 enabled browser.
===================================================

This was started as a port of Lazarsoft’s qrcode reader.

It is a maintained fork, so feel free to open issues or PR !


Installation
============

``
npm install qrcode-reader
`

Usage
=====

`
var QrCode = require('qrcode-reader');
`

Create a new instance of QrCode:

`
var qr = new QrCode();
`

Set its callback to a custom function:

`
qr.callback = function(error, result) {
if(error) {
console.log(error)
return;
}
console.log(result)
}
`

Passing image data in node
==========================

You have to use an external imageparser

1. You can use npm install --save jimp which doesn't have any dependency (runs in pure node).

`javascript
var Jimp = require("jimp");
var buffer = fs.readFileSync(__dirname + '/image.png');
Jimp.read(buffer, function(err, image) {
if (err) {
console.error(err);
// TODO handle error
}
var qr = new QrCode();
qr.callback = function(err, value) {
if (err) {
console.error(err);
// TODO handle error
}
console.log(value.result);
console.log(value);
};
qr.decode(image.bitmap);
});
`

2. You can use npm install --save image-parser, which depends on lwip or graphicsmagick

`javascript
var ImageParser = require("image-parser");
var buffer = fs.readFileSync(__dirname + '/image.png');
var img = new ImageParser(img);
img.parse(function(err) {
if (err) {
console.error(err);
// TODO handle error
}
var qr = new QrCode();
qr.callback = function(err, value) {
if (err) {
console.error(err);
// TODO handle error
return done(err);
}
console.log(value.result);
console.log(value);
};
qr.decode({width: img.width(), height: img.height()}, img._imgBuffer);
});
`

Passing image data in the browser
=================================

Since the browser contains the Image global, we can use it to open images with URL, Data URI, ...

Decode an image by its URL or Data URI:

`

qr.decode(url or DataURL);

`

Decode an image by context.getImageData: Works with web workers.

`

var context = canvas.getContext("2d"); var data = context.getImageData(0, 0, width, height);

qr.decode(data);

`

====================

If you want, you can build the script yourself.

First clone the repository, then from the directory of this repository, do:

`

npm install

`

To run the build process and generate a JavaScript file called dist/index.js you can run from node:

`

npm run build

`

To run the tests:

`

npm test

`

Make it work in the browser
===========================

The generated file dist/index.js works in the browser.

You will have access to the global variable QrCode if you do the following in your HTML:

\\\

\\\

See examples/browser-upload/index.html for a very basic example using a file upload.

Changelog
=========

See CHANGELOG.md`\.