Abstract
This paper proposed an algorithm for image authentication and verification. The algorithm is based on public key. The owner of image extracts the information as watermark information from the image which he wants to transmit to others. The owner embeds the watermark information into the image with public key. Anyone can judge the valid of the watermarked image, and locate the place which has been tampered. Experimental results show that the algorithm is better than the approximate image message authentication codes (IMACs).