Authentication of digital visual data using discrete wavelet transform and TLBO

The main issue in the digital content marketplace is copyright protection of digital content. Sometimes the digital information may copy or alter during transmission. Thus, there is a need to develop an authentication method, which is very effective to protect the digital data. There are different watermarking techniques, which use different transforms. In this paper, a Discrete Wavelet Transform (DWT) along with optimization technique is used to embed the watermark image into the selected image blocks. In a first of its kind, this paper applies Teaching-Learning-Based-Optimization (TLBO) algorithm along with DWT to authenticate the digital visual data. Here, optimization is used to maximize the Peak-Signal-to-Noise-Ratio (PSNR) and the Normalized Cross-Correlation (NCC). The PSNR and the NCC are used to check the efficiency of the proposed algorithm. The experimental results reveal that the proposed algorithm has high imperceptibility and robustness. Different attacks, such as JPEG compression, rotation, Gaussian noise, cropping, and median filter are applied on watermarked images, in order to check the robustness of the proposed algorithm.