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how to add logo in the middle of the qr code using nodejs

javascript node.js qr-code

ramb tumber

asked 19 Nov, 2020

I am trying to create a logo and try to add a logo in the middle of the qr code and i am able to generate the qr code but unable to get the qr code with logo on the middle i have tried this code but unable to get the result getting this error

Error: You need to specify a canvas element

and i am using this library https://github.com/soldair/node-qrcode

and here is the tried code

const QRCode = require("qrcode");
const getQRcodeImage = async () => {
  try {
    let canvas = await QRCode.toCanvas(`my sample text`);

    //adding a log at center
    const imgDim = { width: 30, height: 30 }; //logo dimention
    var context = canvas.getContext("2d");
    var imageObj = new Image();
    imageObj.src = "./Capture.png";
    imageObj.onload = function () {
      context.drawImage(
        imageObj,
        canvas.width / 2 - imgDim.width / 2,
        canvas.height / 2 - imgDim.height / 2,
        imgDim.width,
        imgDim.height
      );
    };
    return canvas;
  } catch (e) {
    console.error(e);
    return "";
  }
};
getQRcodeImage();

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Answer

const QRCode = require("qrcode");
const { createCanvas, loadImage } = require("canvas");
async function create(dataForQRcode, center_image, width, cwidth) {
  const canvas = createCanvas(width, width);
  QRCode.toCanvas(
    canvas,
    dataForQRcode,
    {
      errorCorrectionLevel: "H",
      margin: 1,
      color: {
        dark: "#000000",
        light: "#ffffff",
      },
    }
  );

  const ctx = canvas.getContext("2d");
  const img = await loadImage(center_image);
  const center = (width - cwidth) / 2;
  ctx.drawImage(img, center, center, cwidth, cwidth);
  return canvas.toDataURL("image/png");
}

async function main() {
  const qrCode = await create(
    "http://shauryamuttreja.com/qr/",
    "data:image/png;base64,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",
    150,
    50
  );

  console.log(qrCode);
}

main();

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