IMAGE BASED STEGANOGRAPHY USING DISCRETE WAVELET TRANSFORM AND AES ENCRYPTION

For more details visit http://www.digitronsolutions.in/project-view/5f1aa6bf2c23213200ae6e2b Project Objective. Steganography is the art of hiding the existence of data in another transmission medium to achieve secret communication. The steganography is used for secure communication. In this paper we propose a Discrete Wavelet Transform (DWT) based high capacity steganography using coefficient replacement with increased security by adapting an encryption of payload Image. The Haar and biorthogonal DWT is applied separately on cover image and Advanced Encryption Standard (AES) with modification is applied on payload to convert payload image into an encrypted image. The resulted coefficients of payload image are embedded inside the high frequency bands of cover image. The new concept of replacing HH sub band coefficients by encrypted payload is introduced to generate intermediate stego image. It is observed that the capacity and security are increased in the proposed algorithm compared to existing algorithms. Proposed Technique In this research, Discrete Wavelet transforms have been presented. The secret text is transformed to its Corresponding wavelet coefficients so the cover image. The proposed technique steps are the following: - Read the cover image. - Transform the cover to its wavelet coefficients using 2D DWT. - Read the secret Image. - Apply Advance Encryption Standard(AES) to the secret image and encrypt the image. - Substitute each data in the encrypted secret image to its corresponding ASCII code. - Transform the ASCII code values to the wavelet coefficients using 1D DWT. - From step 2, take the HL and HH wavelet coefficients as cover coefficients, which are used, later in the hiding process. - Classify the HH wavelet coefficients of the cover and then save the positions of the three coefficients types. - Classify the wavelet coefficients of the text (obtained from step 5) - Substitute the HH wavelet coefficients of the cover with the wavelet coefficients of the text in way. From this step, the stego-pixels are generated. - Save the message length within HL. - Find the rows of HL matrix that contains coefficients to hide the positions of stego-pixels. - Generate the stego-image by applying the inverse wavelet transform on the LL, LH, stego HL, and stego HH wavelet quarters.