離散傅立葉轉換及相移鍵控嵌入之浮水印技術研究

陳文淵 ； 劉正忠 ； 劉津榮 ； 程輝男

《勤益學報》 22卷2期 (2004/12) Pp. 59-69

https://doi.org/10.6753/CYJ.200412.0059

摘要

在這科技發達的e世代，網路(internet)與多媒體(multimedia)取代了傳統的郵遞與文字敘述。多媒體資料（聲音，影像，文件與視訊）提供人性化的人機介面，也提供人類在食、衣、住、行、育、樂等各方面的應用，成為現代人類生活上的一部份。文字資料可利用密碼加以保護，多媒體資料則需要浮水印技術來保護。由於數位化的多媒體資料可以經由電腦設備任意的複製修改，而無損其品質，因此尋求一種強健性(robust)的浮水印技術來保護著作權已是商業上迫切的需求。數位浮水印技術與通訊技術一樣，必須能夠抵擋駭客的蓄意破壞，就像是通信系統受到雜訊干擾一樣，仍需完整的取出浮水印來證明版權或所有權的歸屬。本論文基於相移鍵控技術(phase shift keying, PSK)擁有良好的雜訊排除能力，且成功的運用在通訊傳輸上，因此採用來設計強健性的浮水印技術。經實驗結果顯示，離散傅立葉轉換及相移鍵控嵌入之浮水印技術可以抵擋JPEG的壓縮破壞，及數位訊號處理的破壞，如旋轉(rotating)、放大縮小(resizing)、塗抹(painting)、挖除(cropping)、模糊化(blurring)及加雜訊(noising)等，是一種有效的數位浮水印技術。

關鍵字

強健性robust ； 相移鍵控技術phase shift keying, PSK ； 離散傅立葉轉換 ； JPEG壓縮

並列摘要

Nowadays, effective tools and equipment can be easily duplicated, manipulated, and digital multimedia materials broadcast without confinement. A duplication of a digital article can be undistinguishable from the original. Manipulation and editing of digital copies can deceive even the human eyes. Distribution without permission can spread over the world by the internet. Misappropriation of digital assets greatly concerns content owners and creators, especially when the content is made available through the internet. Without the assurance of proper protection against lost revenues, the owners of digital content will be reluctant to make these assets available.
From the internet, the illicit user and hackers can easy to accept, tamper, destroy, and reproduce the valuable message include personal privacy, product skeleton, industrial technique, commercial secret, the military security or multimedia (music, audio, video and texture). Thus, protection of valuable products becomes an important and emergent problem for anyone and anywhere. And developing an effective and secure information hiding method is a task of the engineer.
Watermarking is a potential method for copyright protection and authentication of multimedia data on the internet. In this paper, a novel watermarking scheme using phase shift keying (PSK) modulation with amplitude boost (AB) and low amplitude block selection (LABS) is proposed to achieve superior performance in terms of robustness and imperceptibility. AB is hired to increase the robustness while LABS is employed to improve the imperceptibility.
In order to demonstrate the effectiveness of the proposed scheme, simulations under various conditions were conducted. The empirical results show that our proposed scheme can sustain most common attacks including JPEG compression, rotating, resizing, cropping, painting, noising and blurring etc.

並列關鍵字

Spread Spectrum SS ； Phase Shift Keying PSK ； Discrete Fourier Transform DFT ； Pseudo-random Number sequence PN ； Joint Photographic Experts Group JPEG