Watermarking is a technique for labeling digital pictures by hiding secret information into images.Watermark embedding is a method to discourage unauthorized copying or arrest the origin of the images. In this paper

a new method is proposed.The watermark is processed as a visually recognizable pattern—binary image

which includes more information than the traditional bit streams and is "extracted" instead of only "detected" to characterize the owner.The watermark is hid in the host image by selectively modifying the middle-frequency part of the host image in conjunction with the human visual model and the image cosine transform.Experiments show that this method can survive image cropping and image compression

and get better results

and this is also a prospective method.