Quirc-JpegLib WASM
Wasm Module (compiled using Emscripten) to decode qr code image based on quirc and jpeglib.
Size of the WASM module
The size of the raw WASM module is 250 KB, the gzipped version is 74 KB. The Javascript glue code size is 24 KB, the gzipped version is 7.4 KB.
How to install on your Node JS Application?
Install the package and peer dependencies using your favorite Node Js package manager.
yarn add quirc-wasm-emcc memory-fs fs-extra
Add the webpack plugin to your webpack configuration
const QuircWasmPlugin = require('quirc-wasm-module/dist/webpack-plugins');
webpackConfig = {
plugins: [
// other plugins
new QuircWasmPlugin(), // put this last
],
}
Import the function.
import {decodeQrCode} from "quirc-wasm-module";
Take the jpeg blob, read that blob as array buffer, and pass that array buffer to decodeQrCode function.
canvas.toBlob(blob => {
const reader = new FileReader();
reader.addEventListener("loadend", () => {
const arrayBuffer = reader.result;
const result = decodeQrCode(arrayBuffer);
console.log(result);
});
reader.readAsArrayBuffer(blob);
}, 'image/jpeg');import {decodeQrCode} from "quirc-wasm-emcc";
Using inside a worker
There is a version that works in worker scope under /worker
. You would need to provide self.publicPath
inside the worker scope to work.
An example of using the worker module with comlink
is as follows:
// QuircWorker.jsselfpublicPath = __PUBLIC_PATH__; const QRWorker = ; const QRDecoder = ; const isReady = QRDecoderisReady;const terminate = QRDecoderterminate;const decodeQrCode = QRDecoderdecodeQrCode; // OurModule.jsconst QuircWorker = await import'comlink-loader?multi&inline!../utils/QuircWrapper'; const worker = await ; await worker; // byte array representation of an image containing QR codeconst imageByteArray = ; // the decoded QR code stringconst string = await worker;