A Document Watermarking Algorithm Based on Partitioned Character Image

A novel document watermarking algorithm for authentication, integrity and detection of tampering is proposed. In this algorithm a watermark generated from the characteristic of a binary document image is embedded into the document by modifying the flippable pixels. Experiment show that the watermarked document image has good visual quality and the embedded watermark can be extracted without the original image. This algorithm is sensitive to the content tamper, such as adding, deleting and supplanting and the tamper can be located successfully with the help of a few registration marks. It is also robust to the WINRAR compress attack.