Prevent Image Copying - Slice And Dice
   
Home
 
Books
 
File Formats
 
Glossary
 
Software
 
Tutorials
     
GraphicsAcademy.com  >  Tutorials  >  Prevent Image Copying  >  Chapter 2

How To Prevent Image Copying

Chapter 2: Slice And Dice

Another idea for preventing copying is to slice images up into segments, and then use HTML to put the segments together to present one overall image.

(There is a tutorial on how to slice images up this way on this site: How To Slice An Image Into Smaller Images).

This approach doesn't prevent copying, but it does mean that if a user right clicks and saves one image (or whatever other method they use), they only get one small segment. To get the whole image a user would need to copy all the segments and the code to reassemble them in their web page.

Below is an example of an image that has been sliced into segments using this method. I've separated the segments out (and added borders to each) so that you can see exactly what is going on. In my example, I've chopped the image up into 9 segments, but you could use whatever number of segments suits you.

Please do NOT copy this image it is copyrighted - if you want this and many other images, go buy a copy of Hemera's Photo-Objects 50,000 Premium Image Collection.


Below is what the image looks like when reassembled using HTML. As you can see, it looks as if it's all one big image.


Here is the HTML code that I used:
(If you're not familiar with HTML or just want to learn more, then get yourself a good HTML Tutorial).

<TABLE WIDTH="195" COLS="3" CELLPADDING="0" CELLSPACING="0" BORDER="0" RULES="NONE">
<TR>
<TD WIDTH="70"><IMG SRC="hemcir00.gif" WIDTH="70" HEIGHT="70" BORDER="0"></TD>
<TD WIDTH="55"><IMG SRC="hemcir10.gif" WIDTH="55" HEIGHT="70" BORDER="0"></TD>
<TD WIDTH="70"><IMG SRC="hemcir20.gif" WIDTH="70" HEIGHT="70" BORDER="0"></TD>
</TR>
<TR>
<TD WIDTH="70"><IMG SRC="hemcir01.gif" WIDTH="70" HEIGHT="50" BORDER="0"></TD>
<TD WIDTH="55"><IMG SRC="hemcir11.gif" WIDTH="55" HEIGHT="50" BORDER="0"></TD>
<TD WIDTH="70"><IMG SRC="hemcir21.gif" WIDTH="70" HEIGHT="50" BORDER="0"></TD>
</TR>
<TR>
<TD WIDTH="70"><IMG SRC="hemcir02.gif" WIDTH="70" HEIGHT="70" BORDER="0"></TD>
<TD WIDTH="55"><IMG SRC="hemcir12.gif" WIDTH="55" HEIGHT="70" BORDER="0"></TD>
<TD WIDTH="70"><IMG SRC="hemcir22.gif" WIDTH="70" HEIGHT="70" BORDER="0"></TD>
</TR>
</TABLE>


While this idea works, it's not something that I would recommend doing for a large collection of images - it's just too much work!

There are also a couple of additional issues that you need to be aware of:
  • I recommend caution if you are considering using this technique for JPEG images. The issue is that JPEG, because of the lossy compression algorithm used, may include edge effects which could cause the boundaries between the segments to show up as faint lines or other artifacts.

  • Sliced up images usually take more storage and bandwidth than the original image. This is because each separate segment file duplicates header and palette information, and because compression is usually not as effective on small files as large. In the example shown on this page, the original image was 28,541 bytes in size, but when divided up into nine segments, the segments totalled 35,362 bytes in size.

Web Hosting


  
How To Prevent Image Copying:
 
 
  << PreviousIntroduction   1   2   3   4   5Next >>  
   

Web Hosting

 
   
 
Privacy     Terms Of Use

Copyright © 2005-2008, Answers 2000 Limited

With any business, it is up to the individual owner of said business to ensure the success of the business. You may make more or less than any sample figures or results that might be quoted on our web sites or other publications. All business involves risk, and many businesses do not succeed. Further, Answers 2000 Limited does NOT represent that any particular individual or business is typical, or that any results or experiences achieved by any particular individual/business is necessarily typical.

In Association With Amazon.com
All trademarks are property of their respective owners.
All third party content and adverts are copyright of their respective owners.

Some graphics on our web sites are Copyright (C) 1997-2000 Hemera Technologies Inc., and used under license. All such pictures are provided for viewing purposes only and are not to be saved or downloaded. All such pictures of recognizable individuals are models and used for illustrative purposes only, and not meant to imply any association or endorsement of said individual with any product or service.