Digital Image Cryptography Using Combination of Arnold's Cat Map and Bernoulli Map Based on Chaos Theory

Data security is a very important requirement in information technology. Irresponsible parties can access data transmitted over the internet so that it can be detrimental to the data owner. Data security system is needed when data will be sent to other parties. Cryptography is a technique for data security with concept of making data unreadable by everyone. There are various kinds of techniques and algorithm to encode data. The cryptographic method in this study is by implementing chaos theory using Arnold’s Cat Map and Bernoulli Map algorithms. The two algorithms are combined and produce encryption techniques to increase the security of the data sent by the sender to the recipient without being known by others. The algorithm is applied to process of encryption and decryption in grayscale and RGB digital images. The results of this study indicate that image file can be encrypted properly. The time of the encryption and decryption process depends on the size of the image. Histogram shows the difference between original image and encrypted image. Low PSNR values in encrypted image indicate good image quality. The distribution of pixels that spread on the encrypted image explains the low correlation of pixels