Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
An image encryption algorithm robust to post-encryption bitrate conversion
Download
index.pdf
Date
2006
Author
Akdağ, Sadık Bahaettin
Metadata
Show full item record
Item Usage Stats
214
views
125
downloads
Cite This
In this study, a new method is proposed to protect JPEG still images through encryption by employing integer-to-integer transforms and frequency domain scrambling in DCT channels. Different from existing methods in the literature, the encrypted image can be further compressed, i.e. transcoded, after the encryption. The method provides selective encryption/security level with the adjustment of its parameters. The encryption method is tested with various images and compared with the methods in the literature in terms of scrambling performance, bandwidth expansion, key size and security. Furthermore this method is applied to the H.263 video sequences for the encryption of I-frames.
Subject Keywords
Electronic Computers.
,
Computer Science.
URI
http://etd.lib.metu.edu.tr/upload/12607710/index.pdf
https://hdl.handle.net/11511/16335
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
An image retrieval system based on region classification
Özcanli-Özbay, Özge Can; Yarman Vural, Fatoş Tunay; Department of Computer Engineering (2004)
In this thesis, a Content Based Image Retrieval (CBIR) system to query the objects in an image database is proposed. Images are represented as collections of regions after being segmented with Normalized Cuts algorithm. MPEG-7 content descriptors are used to encode regions in a 239-dimensional feature space. User of the proposed CBIR system decides which objects to query and labels exemplar regions to train the system using a graphical interface. Fuzzy ARTMAP algorithm is used to learn the mapping between f...
A Cascadable Random Neural Network Chip with Reconfigurable Topology
Badaroglu, Mustafa; Halıcı, Uğur; Aybay, Isik; Cerkez, Cuneyt (Oxford University Press (OUP), 2010-03-01)
A digital integrated circuit (IC) is realized using the random neural network (RNN) model introduced by Gelenbe. The RNN IC employs both configurable routing and random signaling. In this paper we present the networking/routing aspects as well as the performance results of an RNN network implemented by the RNN IC. In the RNN model, each neuron accumulates arriving signals and can fire if its potential at a given instant of time is strictly positive. Firing occurs at random, the intervals between successive ...
A compact cryptographic processor for IPSec applications
Kavun, Elif Bilge; Akyıldız, Ersan; Yalçın, Tolga; Department of Cryptography (2010)
A compact cryptographic processor with custom integrated cryptographic coprocessors is designed and implemented. The processor is mainly aimed for IPSec applications, which require intense processing power for cryptographic operations. In the present design, this processing power is achieved via the custom cryptographic coprocessors. These are an AES engine, a SHA-1 engine and a Montgomery modular multiplier, which are connected to the main processor core through a generic flexible interface. The processor ...
Performance analysis of reliable multicast protocols
Çelik, Coşkun; Bazlamaçcı, Cüneyt Fehmi; Department of Electrical and Electronics Engineering (2004)
IP multicasting is a method for transmitting the same information to multiple receivers over IP networks. Reliability issue of multicasting contains the challenges for detection and recovery of packet losses and ordered delivery of the entire data. In this work, existing reliable multicast protocols are classified into three main groups, namely tree based, NACK-only and router assisted, and a representative protocol for each group is selected to demonstrate the advantages and disadvantages of the correspond...
A new approach for better load balancing of visibility detection and target acquisition calculations
Filiz, Anıl Yiğit; Can, Tolga; Department of Computer Engineering (2010)
Calculating visual perception of entities in simulations requires complex intersection tests between the line of sight and the virtual world. In this study, we focus on outdoor environments which consist of a terrain and various objects located on terrain. Using hardware capabilities of graphics cards, such as occlusion queries, provides a fast method for implementing these tests. In this thesis, we introduce an approach for better load balancing of visibility detection and target acquisition calculations b...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
S. B. Akdağ, “An image encryption algorithm robust to post-encryption bitrate conversion,” M.S. - Master of Science, Middle East Technical University, 2006.
