Abstract: Steganography is the art and science of hiding information. Steganography methods are categorised into spatial domain and transform domain methods. Transform domain methods are gaining importance as they provide better security compared to spatial domain methods. Among the other transform domain steganography techniques, techniques that use discrete wavelet transform are becoming increasingly popular because DWT has excellent properties suitable for embedding. This paper presents a review on steganography techniques that use discrete wavelet transform.

Keywords: Digital image steganography, spatial domain, frequency domain, DWT.