@nuintun/qrcode

QRCode

A pure JavaScript QRCode encode and decode library.

QRCode guide and demo

QRCode guide

QRCode example

QRCode example use worker

Modify from kazuhikoarase/qrcode-generator and cozmo/jsQR

Usage

Encoder

import { Encoder, QRByte, QRKanji, ErrorCorrectionLevel } from '@nuintun/qrcode';

const qrcode = new Encoder();

qrcode.setEncodingHint(true);
qrcode.setErrorCorrectionLevel(ErrorCorrectionLevel.H);

qrcode.write('你好世界\n');
qrcode.write(new QRByte('hello world\n'));
qrcode.write(new QRKanji('こんにちは世界'));

qrcode.make();

console.log(qrcode.toDataURL());

Constructor

• new Encoder(options?: Options): Encoder

  • version?: number;
  • encodingHint?: boolean;
  • errorCorrectionLevel?: ErrorCorrectionLevel;

Methods

• getMatrix(): boolean[][]

  • Get qrcode modules matrix.

• getMatrixSize(): number

  • Get qrcode modules matrix size.

• setVersion(version: number): Encoder

  • Set qrcode version, if set 0 the version will be set automatically.

• getVersion(): number

  • Get qrcode version.

• setErrorCorrectionLevel(errorCorrectionLevel: ErrorCorrectionLevel): Encoder

  • Set qrcode error correction level.

• getErrorCorrectionLevel(): ErrorCorrectionLevel

  • Get qrcode error correction level.

• setEncodingHint(encodingHint: boolean): Encoder

  • Set qrcode encoding hint, it will add ECI in qrcode.

• getEncodingHint(): boolean

  • Get qrcode encoding hint.

• write(data: string | QRByte | QRKanji | QRNumeric | QRAlphanumeric): Encoder

  • Add qrcode data, if string will use QRByte by default.

• isDark(row: number, col: number): boolean

  • Get byte with row and col.

• make(): Encoder

  • Make qrcode matrix.

• toDataURL(moduleSize?: number, margin?: number): string

  • Output qrcode base64 gif image.

• clear(): void

  • Clear written data.

Custom ECI

import { Encoder, QRByte } from '@nuintun/qrcode';

const qrcode = new Encoder();

qrcode.setEncodingHint(true);

// Custom your own encode function return bytes and encoding
// The encoding value must a valid ECI value
// Custom ECI only support QRByte mode
// https://github.com/zxing/zxing/blob/master/core/src/main/java/com/google/zxing/common/CharacterSetECI.java
qrcode.write(
  new QRByte('hello world', data => ({
    encoding: 26,
    bytes: [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100]
  }))
);

qrcode.make();

console.log(qrcode.toDataURL());

Decoder

import { Decoder } from '@nuintun/qrcode';

const qrcode = new Decoder();

qrcode
  .scan('https://nuintun.github.io/qrcode/examples/qrcode.jpg')
  .then(result => {
    console.log(result.data);
  })
  .catch(error => {
    console.error(error);
  });

Constructor

• new Decoder(options?: Options): Decoder

  • canOverwriteImage?: boolean
  • inversionAttempts?: 'dontInvert' | 'onlyInvert' | 'attemptBoth' | 'invertFirst'
  • greyScaleWeights?: { red: number, green: number, blue: number, useIntegerApproximation?: boolean }

Methods

• setOptions(options: Options): Decoder

  • Set decode options.
    • canOverwriteImage?: boolean
    • inversionAttempts?: 'dontInvert' | 'onlyInvert' | 'attemptBoth' | 'invertFirst'
    • greyScaleWeights?: { red: number, green: number, blue: number, useIntegerApproximation?: boolean }

• scan(src: string): Promise<DecoderResult>

  • Decode a qrcode from image src.
  • Notice: support browser environment only.

• decode(data: Uint8ClampedArray, width: number, height: number): DecoderResult

  • Decode a qrcode from image data.