Image protection
| Previously we discussed optimising graphics and pictures to improve ranking in image searches. But there are times when you may not wish your pictorial content to be indexed by search engines.
For instance, you may be concerned about your intellectual property being ripped by people using image searches to trawl for ‘free’ content. Or worried about image spiders chomping through your monthly quota of bandwidth. While it is difficult to defeat the determined copyright thief, there are a number of ways to make life awkward for them and to deter others. Looking at prevention first, freeloaders hunting down images to steal will have an uphill battle if the search engines don’t index your images. Spiders and Robots To explain the background here, search engines send out special software programs called spiders or robots to index the web. When they arrive on your site, they immediately look for a file that tells them which parts of your site they can and cannot index. In essence, the robot.txt file is a road map that indicates where the No Entry signposts are located. If you wish to put all your images out of bounds to all image search engines the text file would read: User-agent: * Or, you can drill down further and specify a particular image by using: User-agent: * Be careful to specify the images folder rather than the root directory or search engines will not index your site at all. The * asterisk symbol indicates all search engines. However, you can exclude only certain image search robots by naming them in the User-agent field. See Google’s robot.txt advice as an example. Lock Out Of course, there are no guarantees every robot will play by the rules, so to bolt shut your images folder you need to apply password-protection. Most web hosts offer this option in your online control panel. Not everyone is comfortable with, or has access to, their server’s configuration in order to post a robot.txt file. Other means of making the point about copyright and image protection can be made from within the HTML coding. Disabling right-clicking on an image is one route. But be aware that the vast majority of users probably have no intention of ripping the image for commercial use and may be understandably offended by a right-click script accusing them of loitering with intent. At the end of the day, the cons probably outweigh the pros when you consider right click scripts won’t work with:
If that’s not enough, disabling the right click also denies the user access to other right click functions such as Back, Forward, Create a Shortcut, Add to Favourites, Print, etc. which you do wish them to use. Free Scripts Nonetheless, if you do wish to bar right-clicking there are scripts freely available which do the job with or without pop up alert boxes. Below is one example of a no right click script. Paste this code into the <HEAD> of your HTML document <HEAD> <SCRIPT LANGUAGE="JavaScript1.1"> <!-- Begin document.onmousedown=right; Slightly less of a sledge-hammer is the alert box that visitors have to OK when they enter a page. The following is a nice script for a gateway to a gallery: <html> <head> <body onLoad="loadalert()"> A less obtrusive and ‘in yer face’ approach is the addition of an opaque spoiler layer. This allows right-clicking but the downloaded image is blank. To achieve this effect, the image has to be placed as a background within a Span Tag or table and then a transparent image overlaid. Viewed via a browser, the image is perfect. When right-clicked, though, all that is downloaded is the transparent image. Be sure to test out the overlay in as many browsers as possible including Netscape and Macs to check the effect works properly. Again, the shortcoming here is that the image is still “steal-able” from the browser’s cache. Serve Notice Image rollovers or hotspots where an image or pop up is called in whenever the mouse passes over a designated section of the page can also be deployed. By careful placing of the rollover one copyright notice could serve the whole site and be less likely to irritate your audience. Most HTML editors have a rollover option in the Insert Image command where you simply select which of the two images to use. Ensure you make the images pre-load for the effect to work smoothly. Much the same sort of idea can be attained by the low-tech insertion of a copyright notice in the Alt Tag, which does not rely on the web site visitor having JavaScript enabled for a rollover. Ultimately, these methods will merely deter or hinder someone determined to acquire your images for unauthorised use. To combat commercial-scale piracy if, say, you are a photographer with a web site, the safest means of image protection is expenditure on digital watermarking or encryption. A balance, therefore, has to be struck on this issue. A statement of acceptable use should be included in your web site’s Terms and Conditions and reinforced with a gentle reminder elsewhere within the site, e.g. on the first page of your gallery. The vast majority of web site visitors would expect a photography site to explicitly warn users about copyright breach. But they would be much less tolerant of a site that sells machine sprockets and has an array of counter-measures to protect the catalogue photography of its 200-strong sprocket range. A more pro-active and potentially profitable approach to protecting content is to invite users wishing to use your intellectual property to contact you. This way you get to know who is interested in your content, take steps to regulate its use and insist on a credit and link back to your site. Who knows? It may even lead to the creation of new trading or strategic alliances being set up that might not otherwise have happened without the advent of the internet... Links in this story
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