base64 image code not work in gmail

I use zend_mail and render smarty tpl with email template. I try to send logo in email message (code using base64):

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAO8AAAA1CAYAAACp1bzwAAAACXBIWXMAAA7CAAAOwgE...

This doesn't work in gmail, the image is still hidden...

I found this: Base64 images to gmail but I don't know how to load headers, i tried use

$mail->addHeader(...);

but it doesn't bring any effect, how can i solve this problem to code logo in base64 to work in any email client ?