Image matching between scrambled images for secure data management

We propose a scrambling method for image matching using phase-only correlation (POC) or discrete cosine transform sign phase correlation (DCT-SPC). The proposed scrambling method distorts only the phase, which has significant information of images. The information in each image is protected by the distorted phase information. In addition, synchronized scrambling keeps the relative relation between images. Therefore, either POC or DCT-SPC can be directly applied to the scrambled images in order to estimate the translated, rotated, and scaled values. Moreover, the proposed scrambling does not affect the accuracy of estimation values.