A webassembly build of C/C++ Zbar barcode scanning library.
Online Demo: https://zbar-wasm.github.io/demo
Install:
npm i zbar.wasm
const { createCanvas, loadImage } = require('canvas');
const { scanImageData } = require('zbar.wasm');
const getImageData = async (src) => {
const img = await loadImage(src);
const canvas = createCanvas(img.width, img.height);
const ctx = canvas.getContext('2d');
ctx.drawImage(img, 0, 0);
return ctx.getImageData(0, 0, img.width, img.height);
};
const url = 'https://raw.githubusercontent.com/zbar-wasm/demo/master/node/test.png';
const main = async () => {
const img = await getImageData(url);
const res = await scanImageData(img);
console.log(res[0].typeName); // ZBAR_QRCODE
console.log(res[0].decode()); // Hello World
};
main();
import { createCanvas, loadImage } from "https://deno.land/x/canvas/mod.ts";
import { scanImageData } from "https://deno.land/x/zbar_wasm/mod.ts"
const getImageData = async (src: string) => {
const img = await loadImage(src);
const canvas = createCanvas(img.width(), img.height());
const ctx = canvas.getContext('2d');
ctx.drawImage(img, 0, 0);
return ctx.getImageData(0, 0, img.width(), img.height());
};
const url = 'https://raw.githubusercontent.com/zbar-wasm/demo/master/node/test.png';
const main = async () => {
const img = await getImageData(url);
const res = await scanImageData(img);
console.log(res[0].typeName); // ZBAR_QRCODE
console.log(res[0].decode()); // Hello World
};
main();
The full documentation for ZBar.wasm can be found on the wiki.
Note that for frontend developer who use webpack to bundle js codes, webpack file-loader is required to load the wasm binary.
Some project like create-react-app already handle this for you. But if you want to use your own webpack config, remember to use file-loader for file zbar.wasm.bin
.
For the reason why not just use *.wasm
extensions, see this issue
ZBar.wasm use emscripten to compile C++ code into webassembly.
The default Makefile use docker to provide emscripten environment.
Make sure docker
is accessabled by the user that running Makefile, or override the variables in Makefile to change the toolchains for building.
To build:
npm i
npm run build
npm run test