Image compression operator based on discrete cosine transform was brought up. A securer scrambling locational operator was put forward based on the concept of anti-tamper radius. The basic idea of the algorithm is that it first combined image block compressed data with eigenvalue of image block and its offset block, then scrambled or encrypted and embeded them into least significant bit of corresponding offset block. This algorithm could pinpoint tampered image block and tampering type accurately. It could recover tampered block with good image quality when tamper occured within the limits of ...
