An Anti-JPEG Compression Digital Watermarking Technology with an Ability in Detecting Forgery Region for Color Images

A watermarking algorithm for color images was proposed, which is resistant with the JPEG lossy compression and can locate tampered regions. Through a certain mathematical operation with an Arnold scrambled key image and low DCT coefficients of the original image, a chaotic initial value can be obtained, and then the watermark information can be generated by iterating the Kent chaotic maps. Corresponding to the applicable block index of the image, the watermark information is embedded in the specific positions of the middle DCT coefficients to get the watermarked image. Experimental results show that the proposed algorithm has a strong robustness against JPEG lossy compression and can keep false alarm ratios 0 when the quality factor of the JPEG compression is beyond 35, moreover, it can detect the accurate locations of the malicious tampers.