Color Image Steganography by Using Dual Wavelet Transform (DWT, SWT)

Aarti Dalvi, R. S. Kamathe

Abstract: The aim of steganography is to hide the existence of the embedded information within carriers. Different types of multimedia carriers can be used for steganography like Video, Audio, image etc. In this project Image is used as a carrier. Here ?Cover image? is the color image and ?Secret image? is the grayscale image. This algorithm first separates RGB color planes of cover image. Then extracts either Discrete Wavelet Transform (DWT) or Stationary Wavelet Transform (SWT) coefficients of both B plane of cover image and secret image. These two extracted coefficient values are fused into single image by using wavelet based fusion technique. By taking IDWT/ISWT of fused image the stego image is obtained. Different combinations of DWT and SWT can be used for embedding process (DWT-DWT, DWT-SWT, SWT-DWT, and SWT -SWT). The same combination of transforms is used in extraction process. Here, we concentrated for perfecting the visual effect of the stego image and robustness against the various attacks by using different wavelet families.

Keywords: Color image steganography, DWT and SWT, fusion process, Wavelet families