Innovative image watermarking technique for image authentication in surveillance applications

An image watermarking technique is proposed for image authentication, developed in particular for surveillance applications. This algorithm guarantees mark invisibility and maximum sensitivity to any forgeries. It is based on Walsh Hadamard frequency transform and on MD5 message digest algorithm. The detection algorithm is able to determinate if a watermarked image has been forged and even locate the part that has been changed. This way, both image authenticity and agreement between image and embedded information are guaranteed.