Preventing a visitor from saving an image from my site

Question

What are some effective strategies for preventing the use of my proprietary images?

I'm talking about saving them, direct linking to them etc...

Presently I have a watermark on the image, but I'd rather not.

.NET platform preferred, but if there's a strategy that's on another platform that integrates with my existing application that'd be a bonus.

Answer 1

It's not possible to make it "impossible" to download. When a user visits your site you're sending them the pictures. The user will have a copy of that image in the browsers cache and he'd be able to access it even after he leaves the site ( depending on the browser, of course ). Your only real option is to watermark them :O

Answer 2

You could embed each image inside of a flash application, then the browser wouldn't know how to 'save' the image and wouldn't store the raw jpg in the cache folder either. They could still just press the print screen key to get a copy of the image, but it would probably be enough to stop most visitors.