Forbidden zone data hiding

A new blind data hiding method is proposed based on a novel concept of forbidden zone, where no alteration is allowed in a host signal during message embedding step. Depending on the desired probability of error, the range of the forbidden zone varies, as a compromise between robustness and embedding distortion. Hence, the proposed method makes use of this zone through a single control parameter in conjunction with modulating quantizers for message embedding. The superiority of the proposed scheme over QIM is presented theoretically, as well empirically via simulations. The method is further compared with DC-QIM and its weaknesses and strengths are stated.


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Yüksel, Turan; Yarman Vural, Fatoş Tunay; Akar, Gözde Bozdağı; Department of Computer Engineering (2003)
In this study, a new method is proposed to protect video data through partial encryption. Unlike previous methods, the bit rate of the encrypted portion can be controlled. In order to accomplish this task, a simple model for the time to break the partial encryption by a chipertext-only attack is defined. Then, the encrypted bit budget distribution strategy maximizing the time subject to the bitrate constraint is found. An algorithm to estimate the model parameters is constructed and it isthen implemented ov...
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Tanrıverdi, Güneş; Koç, Seyit Sencer; Department of Electrical and Electronics Engineering (2012)
Radar signal processing techniques aim to suppress clutter to enable target detection. Many clutter suppression techniques have been developed to improve the detection performance in literature. Among these methods, the most widely known is MTI plus coherent integrator, which gives sufficient radar performance in various scenarios. However, when the correlation coefficient of clutter is small or the spectral separation between the target and clutter is small, classical approaches to clutter suppression fall...
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Yalçın, Hüseyin; Bulut, Mehmet Mete; Akar, Gözde; Department of Electrical and Electronics Engineering (2013)
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Okman, O. Erman; Akar, Gözde (2006-08-16)
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Topçu, Osman; Alatan, Abdullah Aydın; Ercan, Ali Özer; Department of Electrical and Electronics Engineering (2013)
This thesis work presents an occlusion-aware particle filter framework for online tracking of multiple people with observations from multiple cameras with overlapping fields of view for surveillance applications. Surveillance problem involves inferring motives of people from their actions, deduced from their trajectories. Visual tracking is required to obtain these trajectories and it is a challenging problem due to motion model variations, size and illumination changes and especially occlusions between mov...
Citation Formats
E. Esen and A. A. Alatan, “Forbidden zone data hiding,” 2006, Accessed: 00, 2020. [Online]. Available: