Cryptography is used for secured data transmission, but the resulted unreadable messages usually attract others attention, so steganography is employed to hide the secret information to prevent attacker from discovering the presence of secret data. This paper proposes an improved technique that combines both Advanced Encryption Standard (AES) algorithm for cryptography and steganography that takes the advantages of using the high frequency coefficients of the cover image by applying the Discrete Wavelet Transform (DWT).The proposed technique is employed to study the effect of hiding the encrypted secret message in 24-bit RGB image. The performance of the proposed method is evaluated in terms of the Peak Signal to Noise Ratio (PSNR) analysis, the payload embedding capacity, and the histogram distribution analysis. Comparison to other four associated works will be offered. Experimental results reveal that the proposed method gives a secure method for data hiding, and shows the robustness against different attacks.
Key words: DWT, Steganography, AES, Cryptography. PSNR, Payload, Histogram.
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