Abstract
We present information hiding system developed using digital watermarking and steganography technologies. In digital watermarking technology, chest CT images of 512×512×16bits (67 slices) were used. The EPR data, the hash value of the regions of interest (ROI) , name of the institute, and the data of the patient support system were hidden in the regions of non-interest (RONIs) in a chest CT image series in the Digital and Communication in Medicine (DICOM) format. A body CT image series of 512×512×16 bits (100 slices) was used for steganography. These CT images were stored in a subfolder after 7-Zip compression. This folder was then embedded in the cover image of a scene photograph. The cover image with the embedded images was then transmitted to other medical institutions. In physical evaluation, the structural similarity (SSIM) and the peak signal to noise ratio (PSNR) of the watermarked image with 4000 words embedded were 0.99 and 65.3 dB, respectively. In addition, when the medical information was embedded in the low-bit plane, such as the first- and second-bit plane, the radiologist was unable to identify the embedded information. In our technology, there was no change in the image capacity of CT images or cover image before and after embedding.
