Quantization index modulation based watermarking using digital holography

Download

index.pdf

Date

2006

Author

Okman, Osman Erman

Metadata

Show full item record

Item Usage Stats

190
views

79
downloads

The multimedia watermarking techniques are evolved very quickly in the last years with the increase in the use of internet. The evolution of the internet makes the copyright issues very important and many different approaches are appeared to protect the digital content. On the other hand, holography is the method to store the 3-D information of an object but it is very applicable to use as a watermark because of the nature of the holographic data. The 3-D object can be reconstructed from the hologram even if the hologram is cropped or occluded. However, watermarking of an image with a hologram is a very novel approach and there are only a few works in the literature which are not very robust against the attacks like filtering or compression. In this thesis, we propose to embed the phase of the hologram to an image using quantization index modulation (QIM). QIM is utilized to make the watermarking scheme blind and degrade the host image as low as possible. The robustness of the proposed technique is also tested against several attacks such as filtering, compression, etc. The evaluated performance of this system is compared with the existing methods in the literature which uses either holograms or logos as the secret mark. Furthermore, the characteristics of the holograms are investigated and the findings about the hologram compression are reported in this work.

Subject Keywords

Telecommunication (including telegraphy, telephone, radio, radar, television)

URI

http://etd.lib.metu.edu.tr/upload/12607506/index.pdf
https://hdl.handle.net/11511/16386

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

A wavalength selectable wdm source using a fiber sagnac loop filter Ergül, Özgür; Ergül, Rüyal; Department of Electrical and Electronics Engineering (2006) The demand for faster data transmission has been increasing since the wide acceptance of the Internet. To meet this ever increasing demand, optical communication systems use Wavelength Division Multiplexing (WDM) to transport more information per fiber by utilizing multiple wavelength channels. Multi-wavelength laser sources are one of the most important components of such WDM systems. In this thesis a multi-wavelength laser source is proposed. A fiber Sagnac loop filter is used to produce a grid pattern wi...
Scheduling algorithms for wireless cdma networks Hakyemez, Serkan Ender; Schmidt, Şenan Ece; Department of Electrical and Electronics Engineering (2007) In recent years the need for multimedia packet data services in wireless networks has grown rapidly. To overcome that need third generation (3G) mobile services have been proposed. The fast growing demands multimedia services in 3G services brought the need for higher capacity. As a result of this, the improvement on throughput, traffic serving performance has become necessary in 3G systems. Code division multiple access (CDMA) technique is one of the most important 3G wireless mobile techniques that has be...
Path extraction of low SNR dim targets from grayscale 2-D image sequences Ergüven, Sait; Demirbaş, Kerim; Department of Electrical and Electronics Engineering (2006) In this thesis, an algorithm for visual detecting and tracking of very low SNR targets, i.e. dim targets, is developed. Image processing of single frame in time cannot be used for this aim due to the closeness of intensity spectrums of the background and target. Therefore; change detection of super pixels, a group of pixels that has sufficient statistics for likelihood ratio testing, is proposed. Super pixels that are determined as transition points are signed on a binary difference matrix and grouped by 4-...
Channel phase and data estimation in slowly fading frequency nonselective channels Zeydan, Engin; Demirbaş, Kerim; Department of Electrical and Electronics Engineering (2006) In coherent receivers, the effect of the multipath fading channel on the transmitted signal must be estimated to recover the transmitted data. In this thesis, the channel phase and data estimation problems are investigated in a transmitted data sequence when the channel is modeled as slowly fading, frequency non-selective channel. Channel phase estimation in a transmitted data sequence is investigated and data estimation is obtained in a symbol-by-symbol MAP receiver that is designed for minimum symbol erro...
Parallel decodable channel coding implemented on a MIMO testbed Aktaş, Tuğcan; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2007) This thesis considers the real-time implementation phases of a multiple-input multiple-output (MIMO) wireless communication system. The parts which are related to the implementation detail the blocks realized on a field programmable gate array (FPGA) board and define the connections between these blocks and typical radio frequency front-end modules assisting the wireless communication. Two sides of the implemented communication testbed are discussed separately as the transmitter and the receiver parts. In a...

Citation Formats

O. E. Okman, “Quantization index modulation based watermarking using digital holography,” M.S. - Master of Science, Middle East Technical University, 2006.