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41.
Abstract— In this paper, several methods to characterize motion blur on liquid‐crystal displays are reviewed. Based on the assumptions of smooth‐pursuit eye tracking and one‐frame temporal luminance integration, a simple algorithm has been proposed to calculate the normalized blurred edge width (N‐BEW) and motion‐picture response time (MPRT) with a one‐frame‐time moving‐window function to LC temporal step response curves. A custom measurement system with a fast‐eye‐sensitivity‐compensated photodiode has been developed to characterize motion blur based on LC response curves (LCRCs). MPRT values obtained by using the algorithm mentioned above and those from the smooth‐pursuit‐camera methods agree. Perception experiments were conducted to validate the correspondence between the simulated results and actual perceived images by the human eyes. In addition, the insufficiency of MPRT to evaluate motion blur on impulse‐type light‐generation LCDs, by analyzing the measurement results of a scanning backlight LCD, is discussed.  相似文献   
42.
Abstract— The luminance of a backlight unit for an LCD TV is adaptively and locally dimmed along with the input video signal in order to reduce the power consumption and also to improve the picture quality. By adopting the zero‐dimensional (0D), 1D, and 2D adaptive dimming techniques, a sample movie having 8.0% post‐gamma average picture levels (APL) could be displayed using 83%, 71%, and 50% of the original backlight power, respectively. For an adoption of the 2D dimming, an LED backlight is preferable. The adaptive‐dimming technique also allows the differential aging characteristics between the LED components and temperature dependence of color and luminance to be overcome. From simulations of a reduction in power consumption, it was found that 40 × 40 pixels is a unit of the local dimming, 30 frames for the sampling period, 24 dimming steps, and an equal‐signal‐step method for determining the dimming factor have been found to be appropriate. The gray‐scale capability of low‐luminance images can also be improved by dimming the backlight luminance and expanding the input signal. By using an LCD TV having an 8‐bit capability, an 11‐bit‐equivalent gray‐scale expression was experimentally proven.  相似文献   
43.
Abstract— The spatio‐temporal aperture and sample rate of a video display determines both the static and dynamic resolution of the video signal that is rendered. The dynamic display characteristics like the visibility of large‐area flicker, motion judder, and motion blur can be derived from the frame rate and the temporal extent of the pixel aperture (i.e., the temporal aperture). For example, liquid‐crystal displays (LCDs) have an aperture that is relatively small in the spatial dimension and wide in the temporal domain. Consequently, moving objects displayed on an LCD suffer from motion blur. Especially in TV applications, the temporal dimension has a large impact on the overall picture quality. The temporal aperture, together with the frame rate, is shown to predict the amount of perceived large‐area flicker, motion judder, and motion blur and also the performance of motion‐blur reduction algorithms for LCDs. From this analysis it is further determined how to obtain the optimal temporal aperture of a television display, for which not only properties of the human visual system (HVS), but also the properties of the video signal have to be taken into account.  相似文献   
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民间剪纸是我国民间美术形式之一,有着悠久的历史。本文从剪纸的构图方法、剪纸的造型手段、剪纸的吉祥祝愿三个方面,分析剪纸的造型特点,从而体现出剪纸的造型源于原始的视觉思维方式和民间审美观念。  相似文献   
46.
We establish a categorical duality for the finitely generatedLindenbaum-Tarski algebras of propositional nilpotent minimumlogic. The latter's conjunction is semantically interpretedby a left-continuous (but not continuous) triangular norm; implicationis obtained through residuation. Our duality allows one to transferto nilpotent minimum logic several known results about inutitionisticlogic with the prelinearity axiom (also called Gödel-Dummettlogic), mutatis mutandis. We give several such applications.  相似文献   
47.
Array automata acting on scenes (two dimensional tapes) are defined. The set of scenes accepted by array automata are proved to be equivalent to the set of arrays generated by array grammars. Certain operators like substitution, homomorphic replication and insertion are extended to sets of arrays. These operators yield interesting classes of pictures.  相似文献   
48.
设计了一种基于IP网络的多媒体教学课件自动生成及播放平台,实现了流媒体、图像、语音、文本、教师板书、桌面和程序等教学信息的融合,自动快速生成课件;并支持基于知识点的检索,创造了一个科学的贴近自然的教学环境。  相似文献   
49.
人体骨架模型的建立   总被引:1,自引:0,他引:1  
周进  刘冀伟  张雷 《微计算机信息》2006,22(19):227-229
人体运动分析在计算机视觉研究领域中具有广泛的应用前景。人体骨架包含了很多的人体运动信息,且简单明了,所以对人体骨架提取具有很重要的意义。本文提出了一种人体骨架模型的建立方法,该方法在骨架提取方面有较强的去噪和抗干扰能力,有很好的鲁棒性,可提取更加有效的骨架图像,进一步结合人体解剖学的基础,建立了人体骨架模型,为人体特征识别(HID)和运动人体的实时追踪打下了坚实的基础。  相似文献   
50.
吴云天  陈永常 《包装工程》2005,26(5):223-224,227
印前设计与制作软件日益丰富多样,支持输出的格式也越来越多.由于跨平台、多软件融合制作及文件的复杂性,需要解决输出时常出现的一些问题.TIFF格式可起到设计与印刷的桥梁作用,从而提高制作和输出所需要的效果.?#  相似文献   
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