Abstract:An image digital watermarking algorithm is proposed,based on blocked wavelet transform and relative quantization which is simple,handy and easy to implement.For the using of quantization scheme,the algorithm can extract watermark without original image and original watermark.Experimental results show that the algorithm has a fine transparency of the embedded watermark image,and the algorithm is very robust against brightness and contrast attacks and is robust against attacks such as JPEGcompression,re-sampl...