1.  Steganography security through obscurity Ryan Zoellner CS 534 Final Project Fall 2013

2. What is Steganography?  “the art or practice of concealing a message, image, or file within another message, image, or file” -dictionary.com  Related to, but different than cryptography  Example: a sender could tattoo a message on a messenger’s head and let their hair grow back; a receiver could shave the hair to reveal the message; outsiders would be oblivious to the message’s existence

3. Project Goals Goal: conceal a hidden image within another, so that a casual observer is unaware of its existence Goal: keep cover image’s quality as high as possible, while still holding enough meaningful info of hidden image Input: can be anything, hidden image is something to keep safe or info to convey; helps to have a cover image with general subject, such as a landscape

4. How? – LSB Method  Choose 2 images: #1: image to conceal #2: image to hide  Create a new image: each pixel will have 16 bits of info for the concealing image and 9 bits of info for the hidden image  For each channel, bits 7..3 contain 7..3 from #1 bits 2..0 contain 7..5 from #2

5. Some Results

6. Recovered

7. Northern Lights as cover image

8. Recovered

9. Camp Randall as cover image

10. Recovered

11. Camp Randall Original

12. Camp Randall cover at 7bits/channel

13. Recovered

14. Future direction  Clearing bits rather than re-using  Comparing various bit-level cover with different types of images  Embedding text messages into images  Attempting different preprocess scrambling of hidden image data before combining