Security of Digital Image Using Hybrid Steganography

Steganography is a technique of information security that hides secret information within seemingly harmless carrier. It is useful for transmitting the secret information over open networks. Steganalysis is a process in which a steganalyzer cracks the cover object to get the hidden data. LSB replacement is the simplest and important technique of image steganography. In this technique the bits are selected based on some criteria and the selected ones are replaced by the bits from secret information. The combination of Huffman Encoding and DCT coefficient based LSB replacement method is implemented in MATLAB and analyzed for the results obtained. Lower the information to be hidden per pixel in carrier image better the stego image can be obtained. Hence better the selection criteria and less the number of bits to alter per pixel can lead to high end result