Show logo in email inbox

Try this:

PHP Code:

$filename = APPPATH.'img/photo1.jpg';
$this->email->attach($filename);

$cid = $this->email->attachment_cid($filename);
$this->email->to($address);
$this->email->message('<img src="cid:'. $cid .'" alt="photo1" />');
$this->email->send(); 


https://www.codeigniter.com/user_guide/l...chment_cid

If i attach picture in email,Yahoo or Google detect it and show in logo header?