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This article argues that papermaking supported cryptanalysis's invention; that cryptology—meaning both cryptography and cryptanalysis—could not be practiced before the sustained production of paper; and that Medieval Arabic cryptology originated in tandem with algebra. Furthermore, this article posits that the regional Islamicate postal service, or thebarīd, was used to relay Medieval Arabic cryptograms and thereby shaped the substance of cryptology. These conclusions stem from examining ninth century to fourteenth century Arabic cryptology as a technology and relating Arabic cryptology to three other technological devices: papermaking in the Middle East, algebra, and thebarīd. Extant documents suggest that cryptology originated in ninth century Baghdad. This is because no cryptanalytical writings are known to exist before this period, and cryptology requires both cryptography and cryptanalysis. However, evidence of Medieval Arabic cryptology exists almost exclusively in practitioners' treatises, not in cryptograms or the working papers of cryptanalysts. To redress this barrier to historical research, I move from text to context, or from the ideas in the treatises to thinking about the technologies these ideas called for. Placing cryptological technology within the wider technological context that inspired, shaped, and confined its development suggests why cryptology originated in the Islamicate world, how Arabic cryptology may have been implemented in practice, and what enabled cryptology's start. I hope that this technological exercise encourages the study of the context in which Medieval Arabic cryptology developed, until further primary sources surface. Furthermore, I intend to demonstrate Medieval Arabic cryptology's relevance to cryptological history and Middle Eastern studies. [ABSTRACT FROM PUBLISHER]

Since H.264/A VC achieves a high compression atio by reducing spatio-temporal redundancy in video equences, the payload of a single packet can often contain a vhole frame encoded by H.264/AVC. Therefore, the loss of a ingle packet does not only cause the loss of a whole frame, `ut also produce error propagation into succeeding frames. ~o deal with this problem, in this paper, we propose a novel ~rame error concealment method for ff264/A VC. First, the iroposed method extrapolates motion vectors from available reighboring frames onto the lost frame. Then, inter-modes of rh macroblocks in the lost frame are adaptively estimated by rsing the extrapolated motion vectors and features of 1.264/A VC. Experimental results exhibit that the proposed ~iethod outperforms the conventional methods in terms of roth objective and subjective video quality. [ABSTRACT FROM AUTHOR]

This paper presents an integrated color imaging system for taking images in extremely high dynamic range scenes. The system first fuses several differently exposed raw images to acquire more intensity information. The effective dynamic range of the image raw data can be extended to 256 times ~five differently exposed images are fused. Then it runs edge detection iterations to extract the image details in different luminance levels. The proposed tone reproduction algorithm equalizes the histogram of the extracted fine edges which tends to assign larger dynamic range for highly populated regions. Finally, the local contrast enhancement is performed to further refine the image details. The experimental results show that the proposed high dynamic range imaging system has good performance on both tone and color reproduction'. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present some sixth-order class of modified Ostrowski’s methods for solving nonlinear equations. Per iteration each class member requires three function and one first derivative evaluations, and is shown to be at least sixth-order convergent. Several numerical examples are given to illustrate the performance of some of the presented methods. [Copyright &y& Elsevier]

Abstract: This paper presents a detailed description of a real-time correlation-based stereo algorithm running completely on the graphics processing unit (GPU). This is important since it allows to free up the main processor for other tasks including high-level interpretation of the stereo results. We first introduce a two-view stereo algorithm that includes some advanced features such as adaptive windows and cross-checking. Then we extend it using a plane-sweep approach to allow multiple frames without rectification. By taking advantage of advanced features of recent GPUs the proposed algorithm runs in real-time. Our implementation running on an ATI Radeon 9800 graphics card achieves up to 289 million disparity evaluations per second including all the overhead to download images and read-back the disparity map, which is several times faster than commercially available CPU-based implementations. [Copyright &y& Elsevier]

Abstract Current implicit blending techniques are mostly designed for use in surface modelling, where only boundaries of the object defined by the implicit primitives are important. In contrast, in volumetric implicit modelling the interior of the object is also significant, which requires different and more suitable techniques for combining implicit primitives. In this paper, we first discuss irregularities that occur using the current techniques. Then, a new technique for blending implicit primitives, especially appropriate in volumetric modelling (e.g., cloud modelling), is introduced. It overcomes these abnormalities and gives us better results than current techniques. [ABSTRACT FROM AUTHOR]