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Design Tip:
Stopping Code And Image Theft

by Larisa Thomason,
Senior Web Analyst,
NetMechanic, Inc.

  
September 2002 (Part 2)
Vol. 5, No. 18
 • Promotion Tip
 • HTML Tip
 • Design Tip
  

Many people think that anything they can access online is free - or should be if it isn't already. They freely copy HTML source code, JavaScript functions, and original images for use on their own pages. While there just isn't a good way to stop them entirely, you can make the task more difficult.

Disable Right Click

Although disabling the right mouse button is commonly used, it isn't a very effective method. Any reasonably experienced visitor can thwart it by disabling JavaScript in the browser!

It's even easier just to select the "View Source" option in the browser. That doesn't use JavaScript, so disabling the right click doesn't have any effect there at all.

If you still want to try it, you can find a lot of free scripts online at the JavaScript.com Web site that disable the right click for the entire page or for images only. But there's a problem with most of the scripts: they haven't been updated to reflect changes in Netscape 6.x browsers. Netscape promised that its version 6 browser would be completely standards-compliant. And it's close.

That's an admirable goal, but unfortunately JavaScript code that worked fine in earlier versions of Netscape won't work in later versions because Netscape declined to make its new version backwards-compliant. Our April 2000 newsletter story explains in detail why Navigator 6 may break your DHTML code.

Betrayed By The Cache

Disabling the right mouse button rarely stops thieves, but it does cause problems for people who want to click their right mouse button for perfectly innocent reasons. They're confused and annoyed when the browser and mouse don't work like they expect.  You may also intrigue them into finding a way to circumvent your protections.

"What are they hiding that's so interesting?" visitors ask themselves - and decide to find out.

And consider this: the browser cache will always betray you in the end! When visitors view your pages in their browsers, all the HTML files, CSS files, JavaScript files, and image files get saved in the browser cache. Visitors can easily retrieve them and open them individually just by searching through the cache directory.

Hiding And Formatting Code

Fortunately, there are more reliable ways to hide important code and make image files less attractive to thieves.

Source code presents the hardest problem. There's really no easy way to keep someone from copying all or part of your source code. However, you can make your code more difficult to copy.

  • External files. Replace the JavaScript functions in your HEAD section with an INCLUDE statement that calls an external JavaScript file (.js). If you're using some DHTML effects that you want to protect, save your style sheet information in an external CSS file (.css).

    Yes, these files are also saved to the browser cache file, but you force the thief to make the extra effort of finding the exact filenames and opening them.

  • Unreadable code. You can make source code virtually unreadable by deleting spaces, line breaks, etc. Not many people have the patience or ability to comb through a page's source code that's all on a single line or two.

    After you change the page, be sure to verify the integrity of the code using HTML Toolbox. When you're deleting line breaks and spaces, it's very easy to accidentally delete part of HTML tags or even page content! Bad HTML code can cause browser compatibility problems bad enough to break pages completely in some browsers.

    Always keep a local copy of the page's source code before you play around with it. Since your goal is a page impossible for humans to read, you'd better keep the original available in case you need to update and maintain it.

  • HTML Code Protection Software: These programs encrypt your HTML code. Visitors may be able to view the source code, but it appears as gibberish. You can view the real code using the encryption software. Research the different products and compare prices by searching on "HTML code protection" in your favorite search engine.

Before you go to all this trouble, ask yourself this question. Are you really sure that you want to make your code off limits to others?

Lots of developers post free JavaScript code at script libraries and bulletin boards. They usually include author and copyright information as comments inside the code snippets. Then they ask users to include those comments with the code and sometimes ask for a link back to the author's Web site.

You might be better off at garnering goodwill and increasing visitors to your site if you do something similar on your page. Even if only a few people link to your site, they may give you a boost in your link popularity score.

Protecting Image Files

Copying a few lines of code is one thing, but image theft is really serious. Many artists and Web designers post their work to sell it online. When people steal the image files and use them on other sites without attribution and without paying for them, the artists are deprived of both publicity and profit.

Fortunately, the methods to protect images are more reliable than those used to hide code.

  • Text Watermarks. Use a text watermark to put copyright information over the image. Visitors can view the image through the watermark, but they wouldn't want to use it on their own sites. When someone purchases an image, send them a clean copy without the watermark.

    About.com has a short tutorial that describes how to add a text watermark in Photoshop. You can also buy standalone programs to add visible watermarks to your images.

  • Digital Watermarks embed identifying information in the image file. It can be an identification number, author information, or any other data that makes the image unique. People don't see the information on the Web page, but you can identify it using graphic program plug-ins or decoding programs. This doesn't keep people from using your images, but it does make the images uniquely identifiable should they be stolen.

    Open your favorite search site and search on "digital watermarks" to learn more about this process and the many manufacturers who produce watermarking software.

Physical and digital watermarks give you the means to prove that someone has stolen your image files, but first you have to determine who is using them without permission.

Some sites make it obvious by using direct linking: they aren't just stealing your images, they're stealing your bandwidth too. You can also search for image files on many search engines. The thieves often don't even bother to rename stolen images so you can search for your image file names and descriptions.

Watermarks allow you to put your best work on your Web site and really show off your design skills. They're a more reliable, professional way to protect your artwork than any special JavaScript tricks you might consider using.



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