In this paper the watermarking programs based on the

discrete cosine transform (DCT) domain DC component (DC) is

adopted. Through adjusting the block DCT coefficient of the image the

watermarks are hidden. And blocking the selected image according to

8×8 pixel, then dividing the selected image into four non-overlapped

sub image blocks according to 4×4 pixel, and thus the watermarks are

embedded through adjusting their DCT coefficient. The experimental

results show that the method has strong robust.