© 2004 Computer Academic Underground
Example of Embedding in Imagery
§An image may have the following three pixels (9 bytes) in it somewhere:
§(01010010, 10010110, 10100100)
§(10110100, 10010001, 01001110)
§(10110110, 00101110, 11010001)
§If we wanted to hide the letter “A” (131 or 10000011), we would use the least-significant bits of each byte:
§(01010011, 10010110, 10100100)
§(10110100, 10010000, 01001110)
§(10110111, 00101111, 11010001)
§
•(Go over the contents of the slide)
•Note again that when using the least significant bits of each byte, only about half of the values are actually changed.  On average this ratio holds true.
•If needed, even the second least-significant bits could be used without the differences becoming noticeable to the human eye, which would double the amount of data an image could potentially hold.