Image zero-watermarking algorithm based on Contourlet transform and singular value decomposition

Abstract

An image zero-watermarking algorithm was proposed based on contourlet transform and singular value decompositon. After the coutourlet transform, the original image was decomposed into series of multi scale, local and directional subimages. The singular value of low frequency component is decomposed. The watermark is embedded and extracted from the first singular value of the every block of image. Experimental results show that the digital image watermarking Algorithm has a good transparence of embedded watermark image and is robust against attacks such as added noise, JPEG compression and cropping. The reliability of watermark extraction was enhanced.