一种基于指纹和可视可擦除水印的安全广播视频分发方案

提出了一种基于可视可擦除水印和数字指纹的多媒体安全分发方案.利用可视水印提供预览视频,支持用户获得授权后的可视水印擦除,伴随擦除过程同时完成用户指纹的嵌入.     

基于Java电化教学中项目驱动教学法的应用

本文提出了以电化教学环境为平台,运用项目驱动教学法进行Java语言的教学,分析并论述了这种教学法在教学过程中的实现思路及实施过程。教学实践表明,本教学方法激发了学生学习的积极性,培养了学生分析问题和解决问题的实际应用能力。     

Accommodation and convergence in integral imaging 3D display

In this paper, we analyze the visual fatigue of integral imaging three‐dimensional (3D) display by studying the accommodation and convergence when viewing the integral imaging 3D images. The theoretical analyses show that there is no inconsistency between the accommodation and convergence distances, which means that the integral imaging 3D display has no visual fatigue. Experiments are implemented, and the results finally demonstrate the rationality of the theoretical analyses. These analyses can be quite beneficial for researchers to better understand the performances and promote the practical applications of the integral imaging 3D display.     

Measurement of minimum angle of resolution (MAR) in the stereoscopic display using the optotype of stereoscopic stimuli

In stereoscopic images, the crossing point of the viewing directions of the two eyes determines the perceived depth. Assuming that accommodation is affected by the positions of the crossing point, the effect of crossing point on minimum angle of resolution (MAR) was investigated. For 40 participants, MAR was measured by two‐alternative forced choice where Snellen optotype E of up and down directions were used as two kinds of stimuli. As the crossing point of the viewing direction of the left and right eyes moves farther from the sample display, the ability to identify the direction of letter E decreases at the optotype of the same line thickness. The change of MAR shows linear trends with respect to the optical power change that are the reciprocal of the distance from the participant to the crossing points located out of screen and on screen.     

Visual experience for autostereoscopic 3D projection display

In order to investigate visual experience for watching the autostereoscopic three‐dimensional (3D) projection display, we conduct a subjective evaluation experiment by a questionnaire when viewing video clips. Factor analysis is adopted to classify the evaluation items for the perpetual constructs of visual experience. Then a mixed design with repeated measurement analysis of variance with dimension and display duration as factors is carried out on the evaluation data to check the factorial effects and interactions for statistical significance. The results of factor analysis extract five factors including visual comfort, image quality, distortion, naturalness, and presence, which can be used as comprehensive indicators to evaluate the autostereoscopic 3D projection display. The results of analysis of variance indicate that image quality, which is used to assess two‐dimensional contents, is no longer applicable. It is necessary to give consideration to depth when evaluating 3D visual experience. Although 3D scenes enhance the overall subjective performance such as naturalness and presence, the health issues and stereoscopic distortion related to the introduction of depth cannot be ignored.     

Response to walnut olfactory and visual cues by the parasitic wasp Diachasmimorpha juglandis

Diachasmimorpha juglandis is a specialist parasitoid attacking fly larvae in the genus Rhagoletis that feed exclusively on walnut fruit husks. In a free-foraging assay comparing response to uninfested, infested, and mechanically damaged fruits, we first determined that D. juglandis use host feeding damage on the fruit as a cue for host presence. In another free-foraging assay that used artificial walnut models and wind tunnel experiments, D. juglandis distinguished infested from uninfested fruits by using either olfactory or visual cues separately. However, the response rate of wasps in the wind tunnel was raised considerably when visual cues were also available. We analyzed the volatile compounds emitted by cohorts of uninfested, mechanically damaged, and infested fruits 1, 3, 5, 8, and 10 days after oviposition by flies into the infested fruits. Total volatile emissions did not differ significantly among treatments, but quantitative changes in volatiles distinguished infested fruits from uninfested and damaged fruits. The fact that parasitoids did not distinguish between infested and damaged fruits in assays where damage was visible indicates that they rely on visual cues when those are available.     

一种鲁棒的可视外壳生成算法*

针对各种传统可视外壳生成算法中数据冗余、精确度低、健壮性不足等问题, 提出了一种新的可视外壳生成算法,即采用加权线段求交、线段集合中心线性过滤、多边形边界检测等方法重建物体模型。与传统方法相比,本算法能够更稳定地计算线段交集,表面边界提取更加准确,重建结果精确逼近真实物体。实验表明, 通过该算法计算的物体可视外壳能够更好地逼近真实模型,精度高。     

网页色彩的导向作用

色彩作为一种重要的设计语言,对于网页设计的影响是深刻而广泛的。从不同的角度分析阐释了色彩作为和线条、文字等一样重要的视觉元素,在网页设计中所起到的重要导向作用以及由此对提高网页信息传递效率的重要影响。     

国内服装品牌在视觉营销中存在的问题

视觉营销是服装界近几年的热门话题,国内各服装品牌也进行了多方面的尝试．针对视觉营销在国内处于起步阶段,在实际操作中存在着许多的问题,分析了国内视觉营销现状,提出了在服装品牌视觉营销中应建立科学规范的视觉营销体系,完善的教育培训机构等应对错施．     

论招贴设计中色彩视知觉的作用

招贴设计中的色彩不仅给人的印象迅速,也起到了加强识别记忆的功能。在解读招贴内容的同时,使人在情感状态上产生多重个性。所以,在招贴设计中如果能够更深层次的了解色彩,并且恰到好处地处理色彩的运用,能起到融合表达功能和情感的作用,具有丰富的表现力和感染力。