Digital Image Encryption and Decryption

As we live and revel in a digital age, the day to day transmission of multimedia data over the internet is beyond our imaginations. Consequently, the increased risk of losing or altering the data during transit is more. Protection of this multimedia data (audio/speech, image and video) becomes one of the major security concerns, because millions of internet users worldwide are infringing digital rights daily, by downloading multimedia contents illegally from the internet. The image protection is very important, as the image transmission covers the highest percentage of the multimedia data. Image encryption is one of the ways out to achieve this. Our world built upon the concept of progression and advancement, has entered a new scientific realm known as chaotic theory. Chaotic encryption is one of the best alternative ways to ensure security. Many image encryption schemes using chaotic maps have been proposed, because of its extreme sensitivity to initial conditions, unpredictability and random like behaviours. Each of them has its own strengths and weaknesses. In this work, we propose a chaotic data encryption method based one dimensional exponential chaotic map. We used the chaotic cryptographic models to encrypt standard images stored in tif format. The experimental result demonstrates that the proposed algorithm can be used successfully to encrypt/decrypt the images with the secret keys.