Previsualizar imagen input file. FROM: http://jsfiddle.net/LvsYc/
function previewImg(event) {
if (event.target.files && event.target.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#img-input-file-preview').attr('src', e.target.result);
};
reader.readAsDataURL(event.target.files[0]);
}
}
$("#img-input-file").on('change', previewImg);
<form id="my_form">
<input type="file" id="img-input-file">
<img id="#img-input-file-preview" src="#" alt="imagen" />
</form>