Re: Inline image spams

> I was thinking today that another option would be to first detect if a
> message contains an inline image and then, if it does, score the email
> based on headers only.

I like the idea, but I wonder if we are an unrepresentative sample from 
whom to draw conclusions about how the public might normally use inline 
images. Might normal (non-spammer) people elsewhere put inline images into 
emails? I just don't know enough about this.

> The beauty of that approach is that any email from a regular
> correspondent containing an inline image will sail through because
> you'll have their normal headers in your database already.

Glad you point that out, this is true. I certainly would not worry about 
such a proposed change, the only way it could cause a false positive would 
be a totally new contact deciding to send me images in the email. But 
generally we call those spammers, so ... yeah I like the idea.

The images are an interesting angle because the spammers are trying to use 
this to evade the scoring which is proving so effective upon text. Even 
with all their random dictionary poisoning attempts, software like 
spamprobe and spamassassin are incredible good at identifying spam. I am 
very tempted to try writing a simple bitmap-image analysis library that 
could quantify some aspect of an image. An easy one would be edge or line 
detection which should differentiate between an image heavy in regular 
shapes like text, versus a photographic image.

Of course this would push the spammers to start creating fuzzy text and 
other unusual graphics, which honestly would bring me a bit of pleasure 
because they really look like fools when they have to convolute their basic 
messages so much. And fewer people fall victim to the spams and scams, so 
that is a good effect too.

It would be exciting to have something like that which could become a score 
input to spamprobe or other software. I've done image analysis before in 
computer vision courses but it was all with Matlab, have never coded it in 
C before. But in principle this could be quite simple, iterative, linear.



-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV