How to get image bytes string (base64) in html5, jquery, javascript?

html, jquery

Solution

You could copy the image to a canvas with the same size using `canvas.drawImage(image, 0, 0)` and then use the `.toDataURL('image/TYPE')` method of the canvas to retrieve the base64 representation of the image. 'TYPE' would then be either jpg, gif or png

Example: Make sure that the current page and the image are both on the same domain, subdomain and protocol otherwise you will get a security error. Also make sure that the canvas has the same width and height as the image

HTML

<img src="whatever.jpg" id="myimage" />
<canvas width="300" height="300" id="mycanvas" style="display: none;"></canvas>

Javascript

var myImage = document.getElementById('myimage');
var myCanvas = document.getElementById('mycanvas');

var ctx = myCanvas.getContext('2d');

ctx.drawImage(myImage, 0, 0);

var mydataURL=myCanvas.toDataURL('image/jpg');

Problem

I have an image in iPhone or Android and I want to pass that file stream or bytes string through jQuery AJAX to Web Service to store file on server. So, in HTML5 how can I get image file (jpg, gif, etc..) bytes string so I can post that to server?

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