  In this paper a 4 x 4 Daubechies transform based authentication technique
termed as SADT has been proposed to authenticate gray scale images. The cover
image is transformed into the frequency domain using 4 x 4 mask in a row major
order using Daubechies transform technique, resulting four frequency subbands
AF, HF, VF and DF. One byte of every band in a mask is embedding with two or
four bits of secret information. Experimental results are computed and compared
with the existing authentication techniques like Li s method [5], SCDFT [6],
Region-Based method [7] and other similar techniques based on Mean Square Error
(MSE), Peak Signal to Noise Ratio (PSNR) and Image Fidelity (IF), which shows
better performance in SADT.
