image drag and drop

Helo,
When you drop an image into a ckeditor the image loads in base64 encoded

How can I capture the event "drop"
for example I would like to replace the code:

<td><h2>drop your image here</h2></td>
by
<td><img src="data:image/jpeg;base64,xx............"></td>

when i drag and drop an image.

thanks.