AL-Rafidain Journal of Computer Sciences and Mathematics

Abstract

The present research was aimed to implement a new Steganographic algorithm for Images in Vector Quantization (VQ) compressed domain, since the compressed image considers a secure cover for data to be embedded to avoid attention of unauthorized persons. Also, it saves the cost and time of transmission and storage. The new algorithm aimed to increase the embedding capacity with maintaining the image quality as well as reducing the time of the extraction process. The algorithm was implemented using Matlab 2009a. It embedded two bits in each index depending on mod 4, and secret key shared between sender and receiver. The algorithm used grayscale and RGB images (BMP and PNG) of different resolutions after compression in order to be used as a cover of secret data which were either as text or image. In the research, the new algorithm provided an acceptable image quality despite of the high embedding capacity that occupy the cover image completely, Also, the codebook was not needed for data extraction which led to reducing the extraction time significantly.