DWT Based Watermarking Algorithm of Color Images

The digital products are copied and transmitted widely with the development of Internet rapidly. The copyright protected, the authenticity and the integrality authenticated are brought at the same time. This paper proposes a digital watermarking embedding algorithm based on discrete wavelet transform (DWT) for color image. The original color image is transformed into the YIQ color space, and the watermark was embedded in both Y component and Q component. The algorithm proposed in this paper can contain more embedding intensity and invisible. The experimental results show that the watermarks are robust against JPEG, filter, crop procession and noise etc.