  Digital watermarking consists on inserting a mark into an image to protect it
against copies. The heaviness of the extraction procedure with the old methods
urged us to look for a new algorithm in the singular values domain which would
be blind : it does not require the original image to extract the mark. We
propose a new robust method which consists on inserting the bits of the mark
into the singular values matrix. Contrary to most of the watermarking
algorithms, it is blind and the results show that our method is robust against
the JPEG compression, the reduction of colors (GIF) and the histogram
spreading. So, we were able to obtain PSNR = 49,63 dB.
