Function dataURLToCanvas

Picviewer CE+/dist.user.js:12384–12400

(dataurl, cb)

        })
    };
    function dataURLToCanvas(dataurl, cb){
        if(!dataurl)return cb(null);
        var ctx = canvas.getContext('2d');
        var img = new Image();
        img.setAttribute("crossOrigin","anonymous");
        img.onload = function(){
            canvas.width = img.width;
            canvas.height = img.height;
            ctx.clearRect(0, 0, canvas.width, canvas.height);
            ctx.drawImage(img, 0, 0);
            cb(canvas);
        };
        img.onerror = function(){
            cb(null);
        };
        img.src = dataurl;
    }
    function urlToBlobWithFetch(urlString, cb){
        fetch(urlString).then(response => response.blob()).then(blob => {
            let ext = extFromMimeAndUrl(blob.type, urlString);