Title: Combined enhanced Caesar cipher algorithm and steganography for biometric security

Authors: S.B. Gurumurthy; Ajit Danti

Addresses: Department of Computer Science and Engineering, CHRIST (Deemed to be University), Bangalore, Karnataka, 560074, India ' Department of Computer Science and Engineering, CHRIST (Deemed to be University), Bangalore, Karnataka, 560074, India

Abstract: When biometrics data is transferred in the network, it is exposed to others, and if a hacker obtains the data on the network, the biometrics system's security is compromised. As a result, it is critical to maintain the data security for biometrics while it is transmitted via an untrustworthy channel. Therefore, we present a steganography technique for biometric data security in this study. First, the fingerprint image (secret image) is converted to generate the encrypted image. To encrypt fingerprint images, an enhanced Caesar Cipher Algorithm (EC²A) has been created. The dual-tree complex wavelet transforms (DTCWT) algorithm is then used to transform the cover image. The high-frequency wavelet transform is selected for data embedding. During the embedding process, the cover image has the encrypted biometric data embedded into it. Following the embedding process, a stego-image is obtained. The peak-signal-to-noise ratio (PSNR), structural similarity index (SSIM), normalised correlation (NC), mean absolute error (MAE), bit error rate (BER), and normalised absolute error (NAE) are used to evaluate the performance of the technique.

Keywords: embedding; biometric; EC²A; DTCWT; dual-tree complex wavelet transforms; steganography; fingerprint image.

DOI: 10.1504/IJSSE.2026.154877

International Journal of System of Systems Engineering, 2026 Vol.16 No.3, pp.290 - 308

Received: 30 Dec 2023
Accepted: 01 Feb 2024
Published online: 17 Jul 2026 *

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