An image watermarking technique using cellular automata transform

Watermarking is a technique embedding hidden multimedia information imperceptibly, such as images and sounds. Generally original image is transformed and coded watermark data is embedded in frequency domain watermarking models. In this paper, we propose a new data embedding method using cellular automata transform (CAT). An original image is CA-transformed and the watermark data is embedded into the coefficients of CA-transformed pattern. Our watermarking model has the flexibility in data hiding. It is possible to embed watermark pattern in many different CAT planes with different rule number parameters and CA bases class of CAT and all kinds of image models such as shape, letter and photo can be used as a watermark data. Using CAT with various rule number parameters, it is possible to get many channels for embedding. So our method can recover the weak point having only one transform plane in DFT and DCT domain methods. The watermarking experiments were conducted to show the validity of the proposed method, and the results show that our method can provide multi frequency domains for embedding watermark.