tailieunhanh - Báo cáo hóa học: " Research Article Audio Watermarking through Deterministic plus Stochastic Signal Decomposition"

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 Audio Watermarking through Deterministic plus Stochastic Signal Decomposition | Hindawi Publishing Corporation EURASIP Journal on Information Security Volume 2007 Article ID 75961 12 pages doi 2007 75961 Research Article Audio Watermarking through Deterministic plus Stochastic Signal Decomposition Yi-Wen Liu1 2 and Julius O. Smith1 1 Center for Computer Research in Music and Acoustics CCRMA Stanford University Palo Alto CA 94305 USA 2 Boys Town National Research Hospital 555 North 30th Street Omaha NE 68131 USA Correspondence should be addressed to Yi-Wen Liu jacobliu@ Received 1 May 2007 Revised 10 August 2007 Accepted 1 October 2007 Recommended by D. Kirovski This paper describes an audio watermarking scheme based on sinusoidal signal modeling. To embed a watermark in an original signal referred to as a cover signal hereafter the following steps are taken. a A short-time Fourier transform is applied to the cover signal. b Prominent spectral peaks are identified and removed. c Their frequencies are subjected to quantization index modulation. d Quantized spectral peaks are added back to the spectrum. e Inverse Fourier transform and overlap-adding produce a watermarked signal. To decode the watermark frequencies of prominent spectral peaks are estimated by quadratic interpolation on the magnitude spectrum. Afterwards a maximum-likelihood procedure determines the binary value embedded in each frame. Results of testing against lossy compression low- and highpass filtering reverberation and stereo-to-mono reduction are reported. A Hamming code is adopted to reduce the bit error rate BER and ways to improve sound quality are suggested as future research directions. Copyright 2007 . Liu and J. O. Smith. 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 The audio watermarking community has successfully adopted frequency-domain masking models .