Watermarking Scheme Based on DCT and DHT

A new watermarking scheme based on DCT and DHT is presented. First,the host image is transformed as a whole by DCT. Second, the low and middle frequency region of the coefficient matrix is transformed by DHT. At last the watermarking image is embedded into the region of the DHT coefficient block. The experimental results show that the scheme is easy to be realized and the embedded watermark is effectively robust against various image processing operations such as JPEG lossy compression, noise, cropping, scaling, filtering etc.