The paper proposes a valid blind image-watermarking algorithm. Especially

the algorithm is also effective for some kind of images that have a lot of white pixels. These special images usually can produce a lot of overflows after being embedded the watermark. Furthermore

the magnitudes of these special images are bigger than usual images in some positions after being transformed. So

these images are hard to get the balance between robustness and transparentness. The method is based on Fourier (FFT) transform. The algorithm embeds the watermarking signal modulated on some fix positions that keep some distance from each other. Furthermore

the paper adds some decimals to the image-signed and choose some interrelated regions to extract the watermarking info during detecting

which reducing some data damage caused by saving the image-signed. Experimental results and attack analysis are given. For different images

the algorithm embeds different parameters during embedding watermarks in order to identify watermarks clearly. For the same image

the parameter of extracting is smaller than the one of extracting and the area of extracting is bigger than the one of embedding. The experiments show that it is transparent

robust

accurate and cost-efficient. Especially

the algorithm is strong to withstand the attacks of cutting

noising

compression

erasing and translation.