28 lines
1.3 KiB
Markdown
28 lines
1.3 KiB
Markdown
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#Stenography
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This challenge uses Stenography to hide an image inside another image.
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The principle behind is quite simple and the technique used here is known as LSB Stenography or "Least Significant Bit" stenography.
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when working with images, each pixel holds an RGB or RGBA value. The least significant bit of each R G or B value changes the color to its immediate neighbor out of a range of 255. The image can later be constructed, however with a loss of data since we can only recover the MSB (Most significant bit)
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This script has been written rapidely and only works for images that have the same since.
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assume the following 2 pictures.
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A christmass cards seems innocent enough that no one will expect something to be hidden there
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and were are going to hide Waldo REALLY well this time
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This script will create the flag picture and looks like this
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When we try to recover it again, the flag will have changed slightly because we are only saving and recovering the MSB but it is still readable.
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The results after decryption looks as follow
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