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Ahmed, Mustafa Sami,Shah, Nor Shahida Mohd,Al-Aboosi, Yasin Yousif,Gismalla, Mohammed S.M.,Abdullah, Mohammad F.L.,Jawhar, Yasir Amer,Balfaqih, Mohammed Electronics and Telecommunications Research Instit 2021 ETRI Journal Vol.43 No.2
The research domain of underwater communication has garnered much interest among researchers exploring underwater activities. The underwater environment differs from the terrestrial setting. Some of the main challenges in underwater communication are limited bandwidth, low data rate, propagation delay, and high bit error rate (BER). As such, this study assessed the underwater acoustic (UWA) aspect and explored the expression of error performance based on t-distribution noise. Filter orthogonal frequency-division multiplexing refers to a new waveform candidate that has been adopted in UWA, along with turbo and polar codes. The empirical outcomes demonstrated that the noise did not adhere to Gaussian distribution, whereas the simulation results revealed that the filter applied in orthogonal frequency-division multiplexing could significantly suppress out-of-band emission. Additionally, the performance of the turbo code was superior to that of the polar code by 2 dB at BER 10-3.
Robust HEVC Video Watermarking Scheme Based on Repetition-BCH Syndrome Code
Ali A.Elrowayati,M.F.L. Abdullah,Azizah Abd Manaf,Abd. S. Alfagi 보안공학연구지원센터(IJSEIA) 2016 International Journal of Software Engineering and Vol.10 No.1
High efficiency video coding (HEVC) was recently introduced two years ago as the new standard for video coding. This new codec will be the most widely prevalent standard. Because of the industry needs for authentication and copyright protection methodologies the robustness of this standard is required to be developed. This paper presents the first robust digital watermarking method for the HEVC based on Repetition- BCH syndrome code technique without intra-frame distortion drift. The objective of this article is to implement a new technique that can offer high robustness against noise channel errors and increase the error detection rate in the HEVC video sequences transmitted over noisy communication channels. The proposed technique does not significantly affect the video quality, nor does it escalate the bitrate. The results show that the proposed technique offers greater robustness against noise channel while preserving good quality for extracted watermark. The proposed technique significantly contributes to the performance of the error detection and correction. In addition, this technique can recover the watermark when the watermarked frames dropping rate is less than 20%.
Digital Image Watermarking Based On Joint (DCT-DWT) and Arnold Transform
Majdi Farag Mohammed El Bireki,M. F. L. Abdullah,li Abdrhman M. Ukasha,Ali A. Elrowayati 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.5
The researcher has adopted a digital watermarking technique which operates in the frequency domain: a hybrid watermarking scheme based joint discrete wavelet transform – discrete cosine transform – (DWT-DCT). Its main objective is to test whether this technique can withstand attacks (its robustness) and invisibility (its imperceptibility), achieved by taking DCT of the DWT coefficients of the LL mid-frequency sub-bands from its band. To ensure security, the secret code (watermark) is scrambled using the Arnold transformation which is embedded in the original host image; only gray-scale digital images are used. The results of this research reveal that the secret code (watermark) is strong enough against threats (noise). Comparative results are measured using signal-to-noise ratio criterions, mean square error and normalized cross correlation. Simulated experimentation is done in Matlab.