Study of probability-based tampering authentication scheme for digital images

• Main Authors: Yin-Liang Wang, 王尹良
• Other Authors: Ching-Sheng Hsu
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/55w4hc

碩士 === 銘傳大學 === 資訊管理學系碩士班 === 97 === In recent years, digital watermarking technology has been widely used for digital images of property rights protection and integrity authentication. Image integrity authentication is usually done by a fragile watermarking scheme, which means to embed an image of feature values as an authentication message. When authenticating image integrity, the embedded authentication message in the image is extracted for comparison with the image feature values to identify whether the image has been tampered with, and if so, locate the affected area. However, such authentication schemes may result in detection error problems. Namely, the tampered area may be misjudged as not having been tampered with, or vice versa. Hence, methods that effectively reduce errors in tampering detection have become an important research topic. This study aims to integrate a probability theory to improve image tampering detection accuracy and precision. The scheme includes two processes: the embedding of an image authentication message and tampering detection. In the image tampering detection process, in addition to identifying whether the image has been tampered with and locating the tampered area, through the authentication message embedded in the image, a probability theory is employed to improve previously obtained detection results to enhance authentication accuracy. The experimental results reveal that the proposed scheme performs better in terms of detection precision and authentication accuracy rate.