Geometric Attack Resistant Image Watermarking in Spatial Domain

Most existing watermarking algorithms cannot re- sist geometric attacks,while most geometric attack resistant wa- termarking algorithms can resist only some degree of geometric attacks.This paper proposed a novel geometric attack resistant image-watermarking algorithm.In the algorithm,for watermark embedding,the original image was divided into sub-images,and then one bit of the watermark information was embedded into each sub-image repeatedly by quantization.For watermark ex- tracting,the watermarked image was divided into sub-images, and then one bit of the watermark information of each sub- image was obtained by majority rule from watermark informa- tion extracted from the sub-image.The algorithm is simple and executs rapidly.The quantity of embedded watermark informa- tion is large and the original image is not needed for watermark extracting.Experimental results show that the algorithm can very effectively resist large degree of geometric attacks and com- pound attacks,and it is also strongly robust against common image processing attacks.