A comparative study on recent image steganography techniques based on DWT

Secure data transmission over the internet is one of the important aspects of the data communication as the data is an important asset for communication over the internet. Thus, data security plays one of the most significant roles for distribution and transmission of information over insecure network. Data security involves protection of data from various types of attacks like intrusion or unauthorized access of data which are carried out over the internet. Different techniques like cryptography, steganography, watermarking or fingerprinting are used to add security to the data transferred over the internet. While cryptography uses encryption of data for the purpose of security, data hiding techniques are used for steganography, watermarking and fingerprinting. Steganography makes use of data compression as well as cryptography to provide a better security for the data. It can be used for different types of data like text, image, audio or video. Data compression techniques like DCT and DWT are used as different transformations for providing a higher security and privacy of the information. In this paper, we study the use of DWT along with different transforms and algorithms in Image Steganography and how it helps in achieving the security for the information hidden in the cover image. We discuss some DWT based image steganography techniques and analyze each of them.