https://rawgit.com/blueimp/JavaScript-Load-Image/master/js/load-image.all.min.js
HTML
<script src="https://rawgit.com/blueimp/JavaScript-Load-Image/master/js/load-image.all.min.js"></script>
<script src="https://rawgit.com/blueimp/JavaScript-Canvas-to-Blob/master/js/canvas-to-blob.min.js"></script>
<h2>Select an image file</h2>
<p><input type="file" id="file-input"></p>
JavaScript
document.getElementById('file-input').onchange = function (e) {
loadImage(
e.target.files[0],
function (img) {
img.toBlob(
function (blob) {
var form = new FormData();
form.append('file', blob, e.target.files[0].name);
}, e.target.files[0].type
);
document.body.appendChild(img);
},
{
maxWidth: 600,
canvas: true,
pixelRatio: window.devicePixelRatio,
downsamplingRatio: 0.5,
orientation: true
} // Options
);
};