Background: Images are widely stored and transformed over public channel for communication,
medical purpose or organizational uses. Mostly the images are collected from the remote location,
therefore the confidentiality of the data becomes the most important matter of concern. The most convenient
way to protect the data (image) is to encrypt it right after the capturing the images from the sensors
at remote locations. There are a large number of patents registered till date. We have covered all the
benchmark and important patents on encryption.
Objective: This paper furnished an enhanced secure encryption scheme to assure the confidentiality of
images at the time of transmission or storage. There are numerous encryption algorithms proposed in
the recent days, most of them are not suitable for image encryption due to their high computational
overhead and design structure. The proposed scheme has comparatively low computational overhead as
it uses 2D DWT for decomposition of the image and chaotic maps for generating pseudo random numbers
Methods: The scheme is based on 2D DWT and chaotic maps. The scheme can be divided into two
basic phases. In the first phase, it permutes the image using pseudo-random numbers generated by Arnold’s
cat map followed by a transformation in 2D DWT for diffusion based on enhanced piece wise
linear chaotic map (EPWLCM).
Results: The proposed scheme was tested statistically with promising results. Therefore, the proposed
scheme is secured from any attack, has light weight and is effective.
Conclusion: The proposed scheme highly reduced the computational complexity, but without compromising
the security. A number of tests were done and the results obtained were satisfactory. The scheme
may simply be modified for color image or any other kind of data encryption.