Enhanced image steganography using AES & SPIHT compression

Steganography is derived from Greek word, `steganos' which refers to covered writing of messages. It is a mechanism of hiding messages or data by embedding them into some other data. Through this mechanism, the secured message can be completely hidden from unauthorized access. In existence, Steganography along with SPIHT compression is done using asymmetric cryptographic algorithm. In this model, Steganography is being employed with SPIHT compression where wavelet transformation of image takes place and AES cryptographic algorithm along Diffie-Hellman key exchange mechanism is used for providing additional security and processing speed. In the proposed system, the secret image is compressed using SPIHT compression and encrypted using cover image. Hence, the encrypted stego image with cover image and secret image is obtained. To perform decryption over the stego-image which, the key is to be exchanged using Diffie-Hellman technique. After decrypting, the image is subjected into SPIHT decompression process which is employed to retrieve the original secret image.