get b64 img

<!DOCTYPE html>
<html>

<head>
    <title>
        doc </title>
</head>

<body onload="">
    <h1 style="color: green">
        tralala
    </h1>

    <img id="img1" src="" alt="">
    <img src="http://placekitten.com/40/40">
    <br><br><br>
    img <br>
    <input type="file" onchange="encodeImageFileAsURL(this)" />
</body>
<script type="text/javascript">
    function encodeImageFileAsURL(element) {
        var file = element.files[0];
        var reader = new FileReader();
        reader.onloadend = function () {
            console.log('RESULT', reader.result)
        }
        reader.readAsDataURL(file);
    }
</script>

</html>