A NEW WATERMARKING SCHEME FOR COLOUR IMAGES CAPTURED BYMOBILE PHONE CAMERAS

摘要

A new frequency domain based watermarking scheme for colour images captured by mobile phone cameras is proposed. The proposed technique embeds personal mobile phone numbers inside the image. The aim of the scheme is to protect the copy right ownership of the image. Each bit of the decimal digits is inserted onto one low frequency coefficient of one of the DCT blocks of the host image. A DCT coefficient selection (DCS) process has been applied to increase the invisibility qualities, this process managed to find the coefficient with the maximum magnitude. Different embedding location depending on the spatial frequencies of the host image will be selected. The proposed algorithm achieves a high PSNR values and is found to be robust against JPEG compression and different image manipulation algorithms.