# Seemingly impossible jpeg trick. **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [August 26, 2003, 5:34am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692 "2003-08-26T05:34:57Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Baraqiyal](https://avatars.discourse-cdn.com/v4/letter/b/ecccb3/32.png) [@Baraqiyal](https://boards.straightdope.com/u/Baraqiyal)\ **Post date:** [August 26, 2003, 5:34am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/1 "2003-08-26T05:34:57Z")
Go [here](http://www.vbulletin.com/forum/). When the image comes up, press CTRL-A to highlight the image (or drag your mouse over it). How’d they do that? Does the image change in browsers other than IE6? I need answers! ---
**Author:** ![Baraqiyal](https://avatars.discourse-cdn.com/v4/letter/b/ecccb3/32.png) [@Baraqiyal](https://boards.straightdope.com/u/Baraqiyal)\ **Post date:** [August 26, 2003, 5:36am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/2 "2003-08-26T05:36:44Z")
Oops, Here’s the link: [![](https://random.waxy.org/images/weblog/bush_magic.jpg) ](https://random.waxy.org/images/weblog/bush_magic.jpg) ---
**Author:** ![Fred](https://avatars.discourse-cdn.com/v4/letter/f/db5fbb/32.png) [@Fred](https://boards.straightdope.com/u/Fred)\ **Post date:** [August 26, 2003, 5:40am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/3 "2003-08-26T05:40:29Z")
There’s a similar image involving flowers and Ronald McDonald holding a scalpal to a child’s face. It apparently doesn’t work in Mozilla. I don’t really know how it works. 🙂 ---
**Author:** ![Zcrysis](https://avatars.discourse-cdn.com/v4/letter/z/c0e974/32.png) [@Zcrysis](https://boards.straightdope.com/u/Zcrysis)\ **Post date:** [August 26, 2003, 5:51am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/4 "2003-08-26T05:51:50Z")
Doesnt work in Opera. Seems to be an IE trick. ---
**Author:** ![Teelo](https://avatars.discourse-cdn.com/v4/letter/t/8491ac/32.png) [@Teelo](https://boards.straightdope.com/u/Teelo)\ **Post date:** [August 26, 2003, 5:56am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/5 "2003-08-26T05:56:03Z")
Oh my, thats really cool **Baraqiyal**. Thanks. ---
**Author:** ![neutron\_star](https://avatars.discourse-cdn.com/v4/letter/n/51bf81/32.png) [@neutron\_star](https://boards.straightdope.com/u/neutron_star)\ **Post date:** [August 26, 2003, 5:56am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/6 "2003-08-26T05:56:47Z")
Do Opera and Mozilla highlight images with blue like IE does? It’s pretty obvious that this JPEG is somehow taking advantage of that. The picture of Bush looks really strange. You can kind of see Saddam’s mustache through Bush’s upper lip. I’m not sure exactly how all of this is accomplished or any of the technical details. Hopefully someone that’s more knowledgeable about digital imagery will come along soon. ---
**Author:** ![Zcrysis](https://avatars.discourse-cdn.com/v4/letter/z/c0e974/32.png) [@Zcrysis](https://boards.straightdope.com/u/Zcrysis)\ **Post date:** [August 26, 2003, 5:59am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/7 "2003-08-26T05:59:37Z")
Nope, you cant highlight an image in Mozilla or Opera [well at least I’ve not found a way too]. It only lets you select the text. ---
**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\ **Post date:** [August 26, 2003, 6:05am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/8 "2003-08-26T06:05:22Z")
Netscape and Opera actually shade images blue or something when you select them; every pixel is changed to be more blue. IE replaces some of the pixels with solid blue, while leaving some of the pixels unchanged. This is probably takes less resources to do, but it doesn’t produce as smooth of highlighting. This picture just takes advantage of that. All the pixels in the hidden image are the ones that aren’t replaced. You can’t make them out unless you replace the rest of the pixels with something else. ---
**Author:** ![Baraqiyal](https://avatars.discourse-cdn.com/v4/letter/b/ecccb3/32.png) [@Baraqiyal](https://boards.straightdope.com/u/Baraqiyal)\ **Post date:** [August 26, 2003, 6:15am UTC](https://boards.straightdope.com/t/seemingly-impossible-jpeg-trick/197692/9 "2003-08-26T06:15:43Z")
Thanks Achernar, makes sense.