Algorithm of Watermarks Embedded in DC Components in DCT

In DCT domain,exist AC and DC,the traditional means is to hide watermarking in the AC components,especially in the middle-frequency coefficients.From robustness,in actual application,watermarks are embedded in DC components since DC components have much larger perceptual capacity than any AC components.Experimental results demonstrate the strategy,which embeds watermarks in DC components is effective and generated good robustness,and images embedded watermarks can withstand attacks which exerted by tailoring,loss compression.