tailieunhanh - Báo cáo hóa học: " Research Article Peak-Shaped-Based Steganographic Technique for JPEG Images"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Peak-Shaped-Based Steganographic Technique for JPEG Images | Hindawi Publishing Corporation EURASIP Journal on Information Security Volume 2009 Article ID 382310 8 pages doi 2009 382310 Research Article Peak-Shaped-Based Steganographic Technique for JPEG Images Lorenzo Rossi Fabio Garzia and Roberto Cusani INFOCOM Department Sapienza Universita di Roma Via Eudossiana 18 00184 Rome Italy Correspondence should be addressed to Lorenzo Rossi Received 1 August 2008 Revised 16 October 2008 Accepted 29 January 2009 Recommended by Andreas Westfeld A novel model-based steganographic technique for JPEG images is proposed where the model derived from heuristic assumptions about the shape of the DCT frequency histograms is dependent on a stegokey. The secret message is embedded in DCT domain through an accurate selection of the potentially modifiable coefficients taking into account their visual and statistical relevancy. A novel block measure named discrepancy is introduced in order to select suitable areas for embedding. The visual impact of the steganographic technique is evaluated through PSNR measures. State-of-the-art steganalytical test is also performed to offer a comparison with the original model-based techniques. Copyright 2009 Lorenzo Rossi et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction Steganography is the art of hidden communication. Its aim is in fact to hide the presence of communication between two parties. Current steganographic techniques conceal secret messages in innocuous-looking data as images audio files and video files. Following the approach in 1 the actual message to be transmitted is called embedded message while the innocuous-looking message in which the other will be enclosed is the cover message cover image in case of images . This embedding process creates a new message called stego .