Image talk:StenographyOriginal.png

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How was this image made? 70.68.203.120 07:02, 26 February 2007 (UTC)

What is hidden in this picture and how can I extract it? -- Taku 01:12, Nov 11, 2004 (UTC)

Is there an original picture so I can compare the two? -- Taku 17:13, Nov 16, 2004 (UTC)

The article on steganography explains how to extract the data, which is this image: Image:StenographyRecovered.png. I followed the instructions and got the hidden image. --Elijah 23:36, 2005 Jan 3 (UTC)

Could someone give an example of "appropriate software"? --Amy

OK. This is what I did:
1. Save the file in *.RAW format with header size 0 (default). You can use Photoshop for this.
2. Take a Hex Editor (e.g. Hex Workshop), and do a & (AND) operation on the file (per 8-bit) with the number 3.
3. Save the file.
4. Open it with Photoshop again (with the same *.RAW settings you saved it with).
5. In Photoshop's menu -> Image -> Adjustments -> Auto Levels (Or you can go to Image -> Adjustments -> Levels... and make it even brighter). -- Wolf359 01:38, Jul 06, 2005 (ISRTC)

Some programs have Image Arithmetic functions that can perform arithmetic on the colour values in an image, which is easier if you don't know what a hex editor is. In Paint Shop Pro:
1. Open the StenographyOriginal.png file.
2. Create a new image with 24-bit colour depth (16 million colours), any size. Fill it with colour #030303 (this looks like black).
3. Go to the menu Image > Arithmetic... Select Image#1: StenographyOriginal.png, Image#2: the 030303 black image, Function: AND, Channel: All channels. Click OK.
4. Create a new 24-bit image and fill it with colour #858585 (looks like gray).
5. Go to the menu Image > Arithmetic... Select Image#1: the 030303 black image, Image#2: the 858585 gray image, Function: Multiply, Channel: All channels. Click OK.
(The reason for steps 4&5 above is that in Paint Shop, increasing brightness just adds to the overall brightness, instead of increasing it proportionally. Using Adjust > Brightness/Contrast leads to a gray box.)
6. Mira! Kittycat! ^_^ --megabigblur

Umh, for steps 4&5 you want to use #555555, not #858585. hex 55 == dec 85. And if you increase Contrast instead of Brightness, it will work with Paint Shop. Per definition, "brightness" modifies by adding/subtracting a constant value, while "contrast" correctly scales the image by a given factor.

For Paint Shop Pro X follow the first three steps above to create the combined image (make sure "Divisor" is set to 1 and "Bias" to 0), then in the menu go to Adjust > Color > Fade Correction to obtain the final image. Unfortunately I don't know what processes are involved here. - Diceman 16:43, 20 January 2006 (UTC)

Actually you can do the same and much more in Photoshop if you have the Filter Factory plugin. For instructions see My Talk Page --Ukdragon37 18:18, 14 October 2005 (UTC)

How do I do this in Paintshop Pro 6?

Never MIND! Dumb QUESTION! That I ASKED!

[edit] PhotoPaint Method

Open image
Set paint color to RGB 3,3,3
Select paintbrush tool
Select "Logical AND" in property bar
Paint over entire image (sets pixel RGB components to the range [0-2])
Select Image / Auto Equalize option (sets pixel RGB components to the range [0,85,170])

sgb 18:54, 7 December 2005 (UTC)