Introduces the concepts of watermarking channel, discusses the problem of the watermarking capacities in the still image by using the information theoretics on the base of JND model.

Error correcting coding(ECC) is applied in the procedure of watermarking embedding and extraction according to the feature of the digital watermarking channel and constructs the function to get the uniform coding rate of ECC.

From the viewpoint of information communication, multiple watermarking is form of data transmission, in which multiple independent watermark messages are sent simultaneously from embedders (or provers) to detectors (or verifiers) on a network-watermarking channel.

The watermarking mainly selected the method which gathered based on the characteristic to carry on the watermark signal inserting,its key was carries on the characteristic analysis to the vector graph,and discovered the good model expression way.

Various digital watermark signals involved in digital watermarking algorithms are discussed and the requisite characteristics of a watermark signal are summarized.

A new method that digital watermarking information was embedded in numerical attribute s Least Significant Bit(LSB) was put forward in view of the existing watermark algorithm s insufficiency.