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February 2013The monthly newsletter by Felgall Pty Ltd

My Word

Images in Emails

I receive quite a few emails where the images don't display because the sender of the email hasn't attached the images the right way. There are two ways to include images in emails and the majority of the emails I see that are supposed to contain images use the wrong one of these two ways.

The first and simplest way to attach images to an email is to upload the images to the web and link to that copy from within the email. This way of including images used to work quite well before spammers realised that the log files on the server where they put the image would record the email addresses of everyone who opened the email. Simply by linking a one by one transparent image into their email the spammer would get a confirmation that someone's email address existed as soon as they opened the email.

To resolve this email programs changed their default settings so that images that are linked into the email are not displayed. In order to display the images in a particular email you need to actually click an additional link to tell the program that you actually want to see the images in this email. This means that you can open the email and examine the rest of the content before deciding whether you want your email address logged in order to see the images. Even web mail programs usually use this approach.

This has severely disrupted many of the emails that you receive where you actually want to see the images and so you might think that they ought to have handled things a bit differently in the way that the email programs decide which emails can display images. At least some email programs do modify this approach slightly in order to allow the images to display automatically if the email address that the email came from has been whitelisted.

In fact email programs ought to have been able to drop support for linked images completely. Not only will an email containing linked images log your address every time you open the email, it will break if the images are ever removed from the server that the email links to. They will also break if you open the email while not connected to the internet (unless the image is still cached). Also they will use more of the bandwidth that your ISP allows you for your internet connection every time you need to download the images.

In the first paragraph I mentioned that there are two ways to attach images. So far I have listed a lot of reasons why the way that most emails seem to use is the wrong way. The second way of attaching images doesn't involve linking to them. Instead the images are embedded into the email itself. This is the method I use for the image that displays at the top of this newsletter.

The first thing that you will notice is that your email program doesn't advise you that there are images in the email and ask if you want to see them. Instead the email simply displays the images without asking. It doesn't need to ask because the images are already there in the email with no link to the internet being required to access them.

Because no internet access is required there is no log record of which email addresses have opened the email. The email can still display the images even if you are not connected to the internet. The images get downloaded once as a part of the email and so if the email is one that you are going to refer to multiple times you save on the bandwidth associated with downloading the images multiple times.

The only negative to this approach is that with the images as a part of the email you end up downloading all the images once whether you are going to open the email or not. Most email programs provide a simple solution to this problem though by allowing you to specify a maximum size of email that you want to have download automatically. For any email that is bigger than that maximum you get to see the subject of the email and the first couple of lines of content prior to deciding whether you want to download or discard the email. This means that if everyone were to send their emails with images attached into email itself rather than linking to them that you might have an occasional email where you need to click an extra link to download the rest of the email but the number of emails where you would have to do this would be far fewer than the number of emails where you'd have to click a link to view the images (and log that you have viewed them so that the sender knows that you are viewing their email).

In my opinion embedding the images into the email itself is by far the better alternative. Particularly where the images are of a relatively small size and so do not add significantly to the size of the email when you do embed them. I almost never allow emails to display linked images as I figure that if the sender really wanted me to see their images then they'd embed them.
 

On Site

Some variety in articles this month with a few ideas I got while setting up a new computer, a few reviews, as well as a few more scripts that I have modernised or added. There will probably be a lot more JavaScript pages added over the next few months as I attempt to update all the scripts that I wrote that do not yet have a copy on www.felgall.com so that I can eventually get to where the latest version of each script is on a site I own.
 

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