Encryption-Then-Compression-Based Copyright Protection Scheme for E-Governance

Abstract

This article discusses a joint encryption-then-compression-based watermarking scheme for copyright protection and content verification in variety of applications. In this scheme, redundant discrete wavelet transform is first performed to decompose the nonsubsampled contourlet transform host image, and then, the singular value decomposition is applied on transformed coefficients of the host image. Furthermore, same procedure is applied for both watermarks (image and PAN No.). The PAN number is encoded by the quick response (QR) code before hiding into the host image. Finally, 2D hyperchaotic encryption is used to encrypt the watermarked image to make our method more secure against attacks. After this, the encrypted image is then compressed via Huffman compression to reduce the size of the image at an acceptable quality of the reconstructed image. Furthermore, performance outcomes confirm better robustness and security of the method while preserving the image quality.