How It Works
This demonstration shows how three bits can be hidden by changing one bit of the data.:
Given some data, you can create any combination of bulbs by flipping just one switch.
- The light switches represent the cover data bits (the LSB of the image pixels)
- The light bulbs represent the secret message bits.
- Each switch is labeled with a binary number (001 through 111)
- When you flip a switch, it toggles the corresponding light bulb(s) based on the binary pattern
- For example, switch "011" will toggle both the 001 and 010 bulbs
- The final state of the bulbs stores three secret bits, while only changing one cover bit.
- This demo uses a block size of three. Some real world stego might use block sizes of 7-15.
- A block size of 7 bits(bulbs) would require 127 bits(switches) but would hide 7 bits for each cover bit changed.
- A block size of 15 bits(bulbs) would require 32767 bits (switches) but would hide 15 bits for each cover bit changed.