Abstract
In this paper, a fast and robust watermark embedding algorithm for H.264 is proposed. This algorithm embeds the watermark in the compressed domain. After the coding block is transformed by DCT (discrete cosine transforms) and quantized, it modifies the sign information of the AC coefficients in the middle frequency and high frequency ranges to embed the watermark. The experimental results show that our watermarking method has higher watermarking capacity than the conventional watermarking methods for H.264/AVC. Also, it doesn’t cost much execution time and the bit-rate of the video sequence increase very little. The watermark is robust against transcoding and common signal processing attacks.