This article recommends [TOOLFK] online QR code decoding, online QR code decoder , you can get the QR code by dragging or uploading the QR code picture, computer camera scanning the QR code, entering the QR code picture address, etc. Content. Website name: ToolFk website link: https://www.toolfk.com/Tool link: https://www.toolfk.com/tool-generate-qrcode?t=qrdecode Code teaching The code base that this tool [online QR code decoding tool] depends on is https://github.com/davidshimjs/qrcodejs STEP 1 STEP 2 The core code is as follows function renderLogo ( canvas, url ) { var img = new Image(), ctx = canvas.getContext( '2d' ), canvasSize = 200 ; if (!url) { ctx.fillStyle = 'rgb(255, 255, 255)' ; ctx.fillRect( 0 , 0 , canvasSize, canvasSize); return ; } img.onload = function ( ) { var imgSize, zoom, imgW = img.width, imgH = img.height; ...