Atext Steganography by Using Image Spatial Domain

Abstract

This dissertation is a description of the information security techniques and in the first place, it aimed to maintain the information security (privacy, Confidentiality) by encrypting it using RSA algorithm and hid it into image spatial domain using different algorithms like Least Significant Bit algorithm ,Convolution or Bit XOR algorithm , Random approach algorithm ,Least Significant Bit based Random approach algorithm and Convolution based Random approach algorithm and hence transmits the image to the Receiver to Extract the information and decrypt it. Also it compares the effect of these algorithms on the image by calculating Mean Square Error (MSE) and Peak Signal to Noise Ratio (PSNR). And also it explains the relation between information Size and image size. By using MATLAB language the Steganography system was implemented and it allow user to select an image and determine the Steganography algorithm and hence enter the information which it can be short message or file. The results were obtained and discussed and it shows that the Random approach algorithms have visible impact on the image appears as black spot while Convolution algorithm or Least Significant Bit algorithm does not have A visible impact on the image because the precision in many image formats is far greater than that perceivable by average human vision. Also the results shows that the Least Significant Bit based Random approach algorithm and Convolution Based Random approach algorithm are the best because the information are embed randomly so no one except the receiver Know the order of the information in side image and this add Another level of security to the information. And it concludes that there are no visible impacts on the image when the PSNR is greater than 40dB and the information size is small compared to the image size.