Protecting Images (and other page content)
Question: How can I block others from downloading/printing/saving images from a web page using HTML or XHTML ?.
just about every web newcomer asks this one
Short Answer: You Can't!.
Longer Answer: Browsers download everything that makes up your web page before displaying your page so if you block downloading then no one will be able to see it. The ONLY way to achieve that is to not put it on the web. Once the browser has downloaded the files you can't stop your visitor doing whatever they want with it including printing it.
To discourage people from stealing your content without interfering with legitimate visitors you can:
- properly optimize your images for the web - this makes their resolution too low for use anywhere else.
- embed watermarks in your images that identify your site. I someone steals your image then it will advertise your site and be obvious that it is stolen. If they try to patch up the image to remove the watermark the resultant loss of resolution will make it unusable.
- The only way to protect your text content is to publish it in PDF format instead of using HTML. You can then set a password to stop the person from editing, copying or prnting the content of the PDF. It doesn't stop them from copying the entire file though. Of course some search engines offer HTML versions of PDFs in their search results so the text could still be obtained that way.
- Any form of encrypton of your HTML and content is useless as the browser needs to be able to decrypt it to be able to display the page and so all anyone needs to obtain a decrypted copy is a browser.
Placing a copyright notice on your page is probably the most effective form of protection since the notice should eliminate theft by those who would have otherwise thought that your page was in the public domain and who respect copyright. It may also make it easier to take legal action against thieves as they will not be able to argue that they weren't aware that they were stealing.
This article written by Stephen Chapman, Felgall Pty Ltd.