Abstract
The fragile digital watermark which proves that the image is authenticity needs tamper resistance. For tamper resistance, it was done by concealing the algorithm of the digital watermark in the past. But there is a limit in the defense by the algorithm concealment. Therefore, we propose the fragile digital watermark algorithm which has tamper resistance even if it makes public algorithm. The algorithm must be applied to JPEG format images. To support JPEG images, digital watermark data is embedded in a parity modulating a quantizatized DCT coefficient by the proposal algorithm.
