Design of a new steganography algorithm based on block and scanning order in digital images

With the rapid progress of the technology, obtaining of digital data has been become very simple. During data transmissions, special and secret data might fall into the hands of third parties. Data can be protected using some data hiding methods during their transmission through communication. Digital images are the one of the places where confidential data transmission can be used. It is possible to provide the desired privacy with steganography, which aims to hide data. In this study, a new algorithm is proposed that is based on block matching and scanning order selection using LSB to hide information in digital images. The fundamental aim of this study is ensuring as few bit changes as possible on the image, and so, firstly the cover image separated into different sub-blocks and each sub-block has a dimension of 8×8 pixels. To find the best block for secret data, the cover image scanned with eight different scanning orders where two of these scanning orders are commonly used and where six of these scanning orders are newly designed. After scanning progress, blocks are selected which need minimum changes and uses the most suitable one of eight scanning orders. Then the secret data can be hidden in these blocks. So that, the stego image which has secret data, includes minimum changes. The image quality of the stego images obtained via the proposed method has been measured with the MSE, PSNR, UQI, M−SSIM, CQM, AD, SC, NCC and NAE image quality metrics, and best results have been achieved. The results of steganalysis, which is the process used for identifying hidden data within stego images, have been verified the robustness of the stego images. Finally, a software is developed to hide data in medical image, to create report about medical image and to analyze medical image.