Hybrid, blind and robust image watermarking: RDWT - NSCT based secure approach for telemedicine applications

Images frequently are helpless to burglary and copyright encroachment. There are numerous events where pictures were illegally copied from websites for utilization or monetary profit and were gotten away from equity, prompting misfortunes for the battled proprietors or innovators. Techniques for securing and recognizing digital pictures and their owners from adversaries are thus required. In this paper, a watermarking procedure in hybrid domain is proposed for copyright assurance of images. The strategy inserts watermarks in Non-Subsampled Contourlet Transform (NSCT) and Redundant Discrete Wavelet Transform (RDWT) areas to accomplish better invisibility, and robustness. The blind extraction of watermark can be performed associating the arbitrarily produced PN arrangements. The experimental results demonstrate that the combination of NSCT - RDWT improves the nature of watermarked image when tried on standard and medical images. The experimental results indicated that the proposed scheme provides good imperceptibility and robustness against various kind of watermarking attacks. The main strength of proposed scheme is that it provides good imperceptibility for watermarked images up to 58 dB along with good robustness for watermark image up to 0.99 against various types of attacks and equally works for various kind of images such as greyscale and medical images. Further, the performance of proposed scheme indicated that the quality of generated watermarked medical image has fulfilled all parameters and benefits for secure telemedicine applications.