Abstract: In order to hide watermark information in the original image better and accelerate detection of the watermark information, the author designed a digital image watermarking algorithm based on compressive sensing and discrete cosine transform (DCT). Firstly, original carrier image was divided into several sub blocks, and discrete cosine transform was used to decompose each sub block. Secondly, compressed sensing was used to process watermark information
 to reduce the amount of embedded information. Finally, the watermark information was embedded into the corresponding position of the original carrier sub block, and the watermark detection was realized by matching pursuit algorithm. The performance of digital image watermarking algorithm was evaluated from two aspects of subjective and objective. The results show that the watermark of this algorithm has good perception, and has good robustness against common attacks. It solves contradiction between watermark transparency and robustness, and accelerates the speed of watermark extraction.

Key words: digital image watermarking, discrete cosine transform, watermark detection, compressive sensing theory, matching pursuit algorithm