TAMPERING DETECTION IN COMPRESSED DIGITAL VIDEO USING WATERMARKING

We presents a method to detect video tampering and distinguish it from common video processing operations such as recompression noise and brightness increase using a practical watermarking scheme for real-time authentication of digital video. In our method the watermark signals represent the macro block''s and frame’s indices and are embedded into the nonzero quantized discrete cosine transform value of blocks mostly the last nonzero values enabling our method to detect spatial temporal and spatiotemporal tampering. Our method can be easily configured to adjust transparency robustness and capacity of the system according to the specific application at hand. In addition our method takes advantage of content-based cryptography and increases the security of the system.