# Image Encryption using Improved Keystream Generator of Achterbahn-128

### Aissa Belmeguenai, Oulaya Berrak, Khaled Mansouri

#### Abstract

The images transmission become more and more widely used in everyday life and even have been known to be vulnerable to interception and unauthorized access. The security of their transmission became necessary. In this paper an improved version of the Achterbahn -128 for image encryption and decryption have been proposed. The proposed design is based on seventeen binary primitive nonlinear feedback shift registers (NLFSRs) whose polynomials are primitive and a nonlinear Boolean function. The outputs of seventeen registers are combined by the nonlinear Boolean function to produce keysteam sequence. The proposed scheme is compared to a Achterbahn-128. The results of several experimental, statistical analysis and sensitivity analysis show that the proposed image encryption scheme is better than Achterbahn-128 and provides an efficient and secure way for image encryption and transmission.

#### References

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#### Paper Citation

#### in Harvard Style

Belmeguenai A., Berrak O. and Mansouri K. (2016). **Image Encryption using Improved Keystream Generator of Achterbahn-128** . In *Proceedings of the 11th Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 3: VISAPP, (VISIGRAPP 2016)* ISBN 978-989-758-175-5, pages 333-339. DOI: 10.5220/0005713503330339

#### in Bibtex Style

@conference{visapp16,

author={Aissa Belmeguenai and Oulaya Berrak and Khaled Mansouri},

title={Image Encryption using Improved Keystream Generator of Achterbahn-128},

booktitle={Proceedings of the 11th Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 3: VISAPP, (VISIGRAPP 2016)},

year={2016},

pages={333-339},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005713503330339},

isbn={978-989-758-175-5},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 11th Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 3: VISAPP, (VISIGRAPP 2016)

TI - Image Encryption using Improved Keystream Generator of Achterbahn-128

SN - 978-989-758-175-5

AU - Belmeguenai A.

AU - Berrak O.

AU - Mansouri K.

PY - 2016

SP - 333

EP - 339

DO - 10.5220/0005713503330339