How do I manually embed images in an email?

Question

There are many questions like this on SO, but the problem is every one of them suggests using some kind of 3rd party library. That isn't an option for me since we use an in-house queueing system, where the email gets put into our database until it's sent.

How can I embed images into emails without using 3rd party software?

Please link us to the potential duplicates that you mention. — Josh Stodola, Jun 28 '10 at 14:49
http://stackoverflow.com/questions/1851728/how-to-embed-images-in-html-email is an example..but like I said these *don't* give me what I want so I'm not sure why you want a link to them. — ryeguy, Jun 28 '10 at 14:54

score 0 · Answer 1 · answered Jun 28 '10 at 15:04

Usually, if you attach an image to the email using the following MIME headers, it will be available to text/html as an image:

Content-Type: image/jpeg
Attachment-Disposition: inline; filename=MYIMAGE.JPG

And then in the message body:

Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 7bit

<html>

    <!-- HTML tags -->
    <img src="MYIMAGE.JPG" />
    <!-- more HTML tags -->

</html>

score 0 · Answer 2 · answered Oct 13 '17 at 07:59

I am using vanilla PHP to send emails with inline embedded images. Core of the code looks like this:

$from = "$from_name <$from_email>";
$reply = "$replyto_name <$replyto_email>";
$to = "$to_name <$to_email>";

$main_boundary = substr( sha1(rand()), 0, 20 );  
$part_boundary = substr( sha1(rand()), 0, 20 );  

$headers  = "From: $from\n";  
$headers .= "Reply-To: $reply\n";  
$headers .= "X-Mailer: PHP script mailer\n";  
$headers .= "MIME-Version: 1.0\n";  
$headers .= 'Content-Type: multipart/alternative;'."\n".' boundary="'.$main_boundary.'"'."\n";

$message=
'This is a multi-part message in MIME format.
--'.$main_boundary.'
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

'.$msgTXT.'

--'.$main_boundary.'
Content-Type: multipart/related;
 boundary="'.$part_boundary.'"


--'.$part_boundary.'
Content-Type: text/html; UTF-8
Content-Transfer-Encoding: 7bit

'.$msgHTML.'

--'.$part_boundary.'
Content-Type: image/png; name="logo.png"
Content-Transfer-Encoding: base64
Content-Disposition: inline; filename="logo.png"
Content-ID: <part1.logo.111@example.com>

<base64 encoded image here>
--'.$part_boundary.'
Content-Type: image/gif; name="logo2.gif"
Content-Transfer-Encoding: base64
Content-Disposition: inline; filename="logo2.gif"
Content-ID: <part2.logo.222@example.com>

<base64 encoded image here>
--'.$part_boundary.'--

--'.$main_boundary.'--

';

$mailsent = mail ($to, $subject, $message, $headers);

What is important:

declare Content-Type as multipart/alternative
use 2 boundary blocks as markers/separators for email main boundary and part boundary for email components inside a main region. Note that it sends text and alternate HTML message. All inline images must be base64 encoded. Please note that \r\n\r\n is to be kept as it is for the code to work, it acts as separators as defined in RFC specifications. Same way one can use this mechanism to send emails with attachments just needs to select proper content-type.

How do I manually embed images in an email?

2 Answers2