Steganography for font-dependant binary documents
Jiancheng Zeng · 2005
In recent years, digital technology has been developing at a tremendous fast speed.Due to the advantages of digital format, the use of digital media (audio, video and images) has been growing rapidly.At the same time, copyright protection problem is becoming a greater concern.Steganography/digital watermarking is thus proposed for these security-related issues.It embeds ownership information into the media content to prevent illegal reproduction and redistribution.Recently, the area of document authentication has gained more and more research interest.In this thesis, we discuss the issues on binary image steganography/watermarking for a secured document authentication system.Compared to gray-level image watermarking, binary document watermarking is much more challenging.The existing algorithms for binary document images either have low embedding capacity, or can cause high distortion in human visual perception.Moreover, most of them are non-reversible algorithms, which limits the application scope of the watermarking system.Being aware of this situation, we propose a fragile watermarking algorithm for binary document images in spatial domain.The proposed algorithm tries to achieve a reasonably high embedding capacity while maintaining high quality for the watermarked image.Two vii