期刊名称：International Journal of Soft Computing & Engineering
电子版ISSN：2231-2307
出版年度：2012
卷号：2
期号：4
页码：113-117
出版社：International Journal of Soft Computing & Engineering
摘要：Digital watermarking techniques have been proposed for handling applications like Copy protection, Content authentication of digital images. Any tiny change to the content is not acceptable in images especially when they are used to store secret information in the form of an invisible digital watermark. To address this present paper proposes a simple block based content checksum watermarking (BCCW) method for image authentication and tamper localization. The proposed BCCW is a hierarchical and block based method. In BCCW the image is divided into sub blocks of size 4×4. Then a hierarchical relationship is established by dividing each 4×4 as a set of four 2×2 blocks. A Checksum of 8 bits is computed from pixels of 4×4 block and the checksum is placed intelligently on the selected 2×2 block pixels. In the proposed BCCW if any block or even a pixel is tampered then the block checksum does not match with the extracted bit sequence. The main advantage of the BCCW scheme is, it can identify effectively in which blocks the tampering has occurred. The experimental results show that the quality of the embedded image is very high, and the positions of the tampered parts are located correctly. The proposed BCCW method is compared with several other methods.
