Résumé
In this paper, a novel steganography method based on the spatial domain and in the human perception is proposed. It does not use the known LSBs bits to embed the infor- mation, instead the secret message is hidden in the fourth bit of the cover-image pixel. The main idea is to change the bit 4 of the pixel in the original image according the bit message. Than modify the other bits of the byte observ- ing that the difference between the new pixel value and the previous one must be equal or smaller than four. We have compared our method with others that work in the spatial domain. We present the results obtained through subjective tests that are based on the levels of human perception. The great difference between our method and the others in the spatial-domain is the fact that we do not use the LSBs bits of the image for embedded the message.