Hiding Information Along Fractal in a Digital Cover to Improve Capacity

Abstract

Steganography is the art and science of secret communication where the message to be hidden is in an invisible form. The message to be transferred is hidden inside an image, known as cover. Once the message is hidden inside the image using a stego key, it becomes a stego image. We need to take care that inserting the secret message inside the cover does not produce any detectable artifacts. If any suspicion is raised our steganography fails. The information needs to be hidden inside the host image with minimal degradation of the host image. The information to be embedded inside the image can be in the form of text, image, audio or video. Generally, a large amount of data can be stored inside the cover. In this paper, we have selected a JPEG image as the cover. Selecting an appropriate cover decides the effectiveness of the steganographic technique. The cover selected should have the large variety of colors. The high-intensity pixel values are selected for hiding data as it is not easy for human eyes to make out the difference in small changes in RGB values. Newton’s fractal is chosen as the stego key to finding redundancy in a digital image and a secret message is embedded in it. The amendment of the host image must not raise any suspicion during transmission. The JPEG image is used to camouflage the information inside it.