An Image Encryption Approach Based on a Two-dimensional Reversible Map
Linjing Li · 2008
An invertible two-dimensional map is applied to the image encryption. Shuffling the positions of image pixels can realize the image encryption. The invertible two-dimensional map can realize the shuffling of the pixels positions. The map consists of a stretch map and a fold map. The stretch operation transforms the original image into a line and the fold operation transforms the line into an image which has the same size as the original one. All maps construct the map set. After the diffusion, the pixel values are changed, then the image is encrypted. The application of the invertible two-dimensional map enlarges the key space of the encryption and enhances the sensitivity to the key changes. The new approach improves the security and shortens the encryption time. The simulation results show that the proposed encryption approach is valid.