function resizedataURL(datas, newWidth, newHeight){
    return new Promise(async function(resolve,reject){
        var img = document.createElement('img');
        img.onload = function(){
                    var canvas = document.createElement('canvas');
            var ctx = canvas.getContext('2d');
            canvas.width = newWidth;
            canvas.height = newHeight;
            ctx.drawImage(this, 0, 0, newWidth, newHeight);
            var dataURI = canvas.toDataURL();
            resolve(dataURI);
        };
        img.src = datas;
    })}//var newDataURI = await resizedataURL(b64data, 50, 50);