CiviMail - Prevent images from being blocked by Outlook
Outlook (and most of the mail clients), block loading external images, because otherwise, the server hosting them would know that you have opened the email (in fact, it's what we do to track the open rate, add a transparent 1x1 pixel image and count when it's displayed)

So to avoid being blocked, you need to send the image as part of the email, not unlike an attachment (with a defined Content-ID:somekey), and as the source of the image (src="cid:somekey") in the mail.

Both of these are not that difficult to implement at the technical level, but might be slightly more tricky in the CKEditor (eg. because it doesn't know it's used to compose an email). 

Unfortunately, no one having that need have contributed the code or funded the development.

Would you be able to step up and make it happen? it would be a nice addition to civimail.