A Secure Image Watermarking Using Visual Cryptography
In this paper we proposed a secure image watermarking algorithm for digital image using the visual cryptography. The proposed algorithm operates in discrete cosine transform (DCT) and discrete fractional random transform (DFRNT) domain which is characteri
- PDF / 376,458 Bytes
- 9 Pages / 439.37 x 666.142 pts Page_size
- 51 Downloads / 194 Views
Abstract In this paper we proposed a secure image watermarking algorithm for digital image using the visual cryptography. The proposed algorithm operates in discrete cosine transform (DCT) and discrete fractional random transform (DFRNT) domain which is characterized by fractional order a and random seed b. In the watermark embedding process of the proposed algorithm some blocks of a cover object is selected randomly, and they are transformed to DFRNT domain. The watermark is generated by the visual cryptography and embedded into the DCT coefficient of the DFRNTed block. The watermark extraction process is the reverse process of embedding process. The proposed watermarking algorithm has high security by the visual cryptography and the randomness of discrete fractional random transform. The experimental results show that the proposed watermarking algorithm is imperceptible and moreover is robust against JPEG compression, common image processing distortions.
Keywords Image watermarking Visual cryptography Discrete fractional random transform Discrete cosine transform Random block selection
1 Introduction As the manipulation of digital content becomes easier, copyright infringement becomes a serious problem. It is important to detect copyright violation and control unauthorized access to digital content. Digital watermarking, which X. Jin J. Kim (&) Deptartment of Copyright Protection, Sangmyung University, Seoul, Korea e-mail: [email protected] X. Jin e-mail: [email protected]
S.-S. Yeo et al. (eds.), Computer Science and its Applications, Lecture Notes in Electrical Engineering 203, DOI: 10.1007/978-94-007-5699-1_19, Ó Springer Science+Business Media Dordrecht 2012
179
180
X. Jin and J Kim
embeds copyright information into digital content, is widely used for authentication and copyright protection of digital content [1–4]. Digital watermarking is a process in which digital content such as image, video, audio, and even text is protected by embedding information such as a hidden copyright message into the content. Such a watermark should be imperceptible to others while being perceptible to the copyright holder who possesses the proper private information key [5]. In the case of image content, digital watermark signals are commonly embedded in the spectral or frequency domain. In particular, several researchers have reported that embedding a watermark in the spectral domain is more robust. Various spectral domain approaches have been used to transform a host image to spectral domains such as the discrete cosine transform (DCT) domain, discrete wavelet transform (DWT) domain, discrete Fourier transform (DFT) domain, and discrete fractional Fourier transform (DFRFT) domain. The watermark is then embedded into the transformed image using certain algorithms. Finally, the watermarked image is transformed back to the spatial domain. Recently, a watermarking algorithm based on discrete fractional random transform (DFRNT) was reported [6], this algorithm exploits the inherent randomness of the transform
Data Loading...
