新型无线手写笔在办公自动化中的应用

针对目前国内办公自动化中纸质文档和电子文档的两重性和不同步性，我们提出手写文档电子化的解决方案。手写文档电子化的最大特点就是当用户在纸质文档上进行常规书写的同时，其笔迹或者信息就直接送到了计算机的电子文档。该方案从根本上解决了长期以来困扰我国信息化推广进程中汉字文化与键盘文化的矛盾。这个技术可以广泛地应用到各种类型的需要用户亲笔笔迹或者手写笔迹的信息系统中，包括电子政务，电子商务，电子税务，电子医务等系统。     

基于曲线拟合的笔迹存储和绘制方法的研究

本文设计了一种基于曲线拟合进行笔迹存储和绘制的方法。该方法综合了反算非均匀B样条控制点算法、deBoor非均匀B样条算法、等距加权采样算法，以及折点识别算法等算法的优点。通过该方法来存储和绘制笔迹，可以减少拟合后笔迹与原笔迹的误差，减小笔迹存储的数据量，并且可以解决笔迹在缩放过程中产生的变形问题。本方法应用于手手写勾画系统中可以取得非常好的效果。     

一种支持多线宽直线反走样算法

直线绘制中出现的锯齿现象称为走样,消除走样的方法称为反走样。文中通过对直线走样产生的原因进行理论上的分析,总结了现有的反走样技术。通过对经典的DDA直线绘制算法和Wu直线反走样绘制算法的研究,在二者结合的基础上,给出了一种任意宽度和复杂背景色下的直线反走样快速绘制算法：对于直线f（x）=mx＋b,0≤m≤1,x轴上每移动一个像素单位,根据直线所需绘制的宽度,在y轴上进行跨度像素着色,填充的色深值取决于该像素到对应直线边缘线的距离、原有背景色深和当前直线绘制色深。对算法进行了去浮点优化,给出了复杂度分析和实验结果,实践证明,该算法有很好的执行效率和反走样效果。     

一种快速的多线宽直线反走样算法

对于直线绘制中出现的锯齿现象称为走样,消除走样的方法称为反走样,通过对直线走样产生的原因进行理论上的分析,了现有的反走样技术。通过对经典的DDA直线绘制算法和Wu直线反走样绘制算法的研究,在二者结合的基础上,给出了一种任意宽度和复杂背景色下的直线反走样快速绘制算法：对于直线f（x）=mx+b,0≤m≤1,x轴上每移动一个像素单位,根据直线所需绘制的宽度,在y轴上进行跨度像素着色,填充的色深取决于该像素到对应直线边缘线的距离、原有背景色和当前直线绘制色。对算法进行了去浮点优化,给出了复杂度分析和实验结果。实践证明,该算法有很好的执行效率和反走样效果。     

面向延迟着色的统一反走样算法

近年来,面向延迟着色的后期处理反走样算法成为实时绘制研究和应用的热点,针对该算法往往只能处理单一类型的走样的问题,提出一种统一的后期处理反走样算法.该算法既能通过子像素级别的几何对几何边界进行高质量的反走样重建,又能根据着色信息对颜色纹理的走样进行形态学的反走样处理;由于使用2种屏幕空间反走样算法分类处理屏幕像素会导致2类像素之间过渡不平滑,在屏幕空间滤波的基础上使用重投影的反走样方法,能克服动态场景中可能出现的闪烁问题.实验结果表明,文中算法在延时绘制的框架下能较好地处理几何边界走样、纹理边缘走样和时间域走样等多种类型的走样,高效地获得高质量反走样绘制结果.     

基于亚像素精度的任意宽度直线反走样算法

针对地图可视化中地图及地图符号边界出现走样现象,提出了亚像素精度的任意宽度直线反走样算法,结合数值微分(DDA)算法和亚像素精度直线反走样算法,计算有宽度直线的边界像素点的整数坐标位置以及像素点的覆盖面积,从而计算边界像素点的绘制亮度,再结合直线的本来亮度值来确定边界像素点的最终亮度值,从而使边界像素变化平滑,减少边界的锯齿.仿真结果表明,改进算法的像素亮度等级能够达到较高等级,生成的地图符号边界比较细腻,反走样效果好,在地图可视化中得到较好的应用.     

Th-Notes多通道共享笔记系统的设计与实现

笔记对课堂学习或参加会议的重要性是不言而喻的。在课堂和会议实现电子化的情况下,它的作用更显重要,其功能也更为丰富。课堂上电子讲稿文件和其它电子媒体的使用既丰富了授课内容,也省略了板书的时间。这提高了讲课的效率和节奏。但也导致学生笔记的速度跟不上教师的讲课速度,造成学生笔记的困难。电子笔记将能帮助学生解决笔记的困难,学生还可通过共享电子笔记来进行讨论。另外缺席的学生还能在事后借助于电子笔记来获取关于教师授课的板书及讲解过程的信息。现有的电子笔记系统已经做了很多尝试,但是都存在这样或那样的缺陷。通过对现有电子笔记系统的分析,以及对改进电子笔记系统的关键技术的研究,提出一个新的电子笔记系统的设计方案。在新的设计方案中,多通道、实时、共享等特性作为系统的特点,而对音频、视频、PPT文档和手写笔记的同步存储采用MPEG7标准和XML技术,解决了多通道信息的存储问题。该系统分为在线学习和离线学习,从六个方面完成整体功能设计,分别是笔处理、麦克风处理、视频显示处理、PPT文档处理、笔记录同步实时存储处理和笔记录检索处理。该系统已经从技术的角度实现了音频、视频、PFT文档和手写笔记同步存储,但是该系统还未能实现通过摄像头进行人脸识别,确定用户身份的功能,系统还有待进一步优化。     

一种基于Word文档的手写批注实现方法

该文讨论了一种基于Word实现的手写批注技术。该技术可以实现在用户使用手写笔对电子文档修改后,保留修改的原始痕迹。这项技术主要应用于电子公文系统的开发,为电子公文系统实现真正的无纸化办公奠定了坚实的基础。     

格式转换在基于仿人摘要系统中的应用

该文的主要内容是描述如何实现～个PDF格式转换模块，并添加到一个通用文档预处理模块结构中来增强系统功能。本预处理模块目前应用于一个新闻自动摘要系统。该系统采用了仿人算法，模拟人在处理摘要时候的思维模式，实现了一系列算法，最终生成了主题明确，反映中心，语句连贯的摘要。而PDF模块的加人，使得整个文档预处理模块的功能大大增强，能够处理文档的范围更加广泛，为进一步的文档信息处理打下了牢固的基础。该文详细分析了该格式的特点和数据存储方式，并提出了合适的解析算法。最后文章还讨论了如何利用设计模式来实现系统的无缝集成以及功能模块的动态添加，使得软件的模块化和可维护性得到了质的飞跃。     

满足文档管理四步应用——文通公司发布文通鉴产品

本报讯记者范向琪报道10月下旬,北京文通信息技术有限公司与图像与语音技术软件供应商美国ScanSoft公司联手推出了一款全新的文档管理平台“文通鉴”产品。文通公司董事长兼总经理沙建辉说:“目前,不管是市场还是用户对电子文档管理缺乏统一的认识和规范,文档管理的概念包括文档获取、文档处理、文档存储、文档应用等各个环节。‘文通鉴’是贯穿文档管理的工具,它面向中文电子文档管理全过程,能够满足用户的不同需求,可完成纸介质文档向电子文档转换、不同格式电子文档的自由转换和调用、快速全文检索和文档原文再现等复杂应用,提升用户的…     

Perception-based fast rendering and antialiasing of walkthroughsequences

We consider accelerated rendering of high quality walkthrough animation sequences along predefined paths. To improve rendering performance, we use a combination of a hybrid ray tracing and image-based rendering (IBR) technique and a novel perception-based antialiasing technique. In our rendering solution, we derive as many pixels as possible using inexpensive IBR techniques without affecting the animation quality. A perception-based spatiotemporal animation quality metric (AQM) is used to automatically guide such a hybrid rendering. The image flow (IF) obtained as a byproduct of the IBR computation is an integral part of the AQM. The final animation quality is enhanced by an efficient spatiotemporal antialiasing which utilizes the IF to perform a motion-compensated filtering. The filter parameters have been tuned using the AQM predictions of animation quality as perceived by the human observer. These parameters adapt locally to the visual pattern velocity     

Stroke-based modeling and haptic skill display for Chinese calligraphy simulation system

The goal of this paper is to study haptic skill representation and display in a Chinese calligraphy training system. The challenge is to model haptic skill during the writing of different strokes in Chinese characters and to achieve haptic rendering with high fidelity and stability. The planning of the writing process is organized at three levels: task, representation and device level to describe the haptic handwriting skill. State transition graph (STG) is proposed to describe switches between tasks during the handwriting. Chinese characters are modeled using 39 typical strokes, which are further grouped into basic and compound strokes. The compound stroke is considered to be sequential combination of the basic strokes. Straight and curve strokes are modeled using line segment and the Bezier curve, respectively. Information from STG is used for real-time collision detection and haptic rendering. Ambiguity of the collision detection at stroke-corner points is prevented using active stroke combined with local nearest point computation. A modified virtual fixture method is developed for haptic rendering. The approach is tested on a prototype training system using Phantom desktop. Initial experiments suggest that the proposed modeling and rendering method is effective.     

What is a pixel?

The total list of processing required to view a pixel includes antialiasing, offset sampling, color space projection, reconstruction filter compensation, compositing, gamma correction, and quantization and dithering. If we look at all these operations we can see a pattern: Almost all of them throw away information. When we filter out high frequencies, quantize intensities into bins, project a continuous color spectrum into three numbers, and represent geometric edges with a single transparency value we can see that an ordinary-hardware pixel, either refreshed on the screen or stored in a file, is simply a bad data compression technique. Any rendering algorithm or image processing operation that converts data to pixels generally loses information about the original data that it uses as input. A few polygons become thousands of pixels; a high-resolution image becomes a low-resolution image. Conversion to pixels for viewing purposes used to be a slow operation, but with faster processors we no longer need to do the image generation offline for speed purposes. We can recalculate the image whenever we need to look at it.     

一种延期着色的快速反走样算法

使用延期着色技术,无法应用硬件对图形进行反走样处理。针对该问题,提出一种延期着色的快速反走样算法。利用缓存的位置和法线信息准确高效地在缓存中进行边缘检测,对边缘部分采用加权抖动采样方法进行平滑处理。实验表明,该算法能够快速地获得效果较好的反走样结果。     

Jim Blinn's Corner-a trip down the graphics pipeline: subpixelicparticles

Reasons for subdividing pixels into subpixelic particles are discussed. Working with subpixel resolution in the floating-point domain is suggested as the easiest approach. To illustrate the use of floating-point pixel space, the arithmetic of two rendering algorithms is reviewed. The algorithms are an antialiased line renderer and a simple polygon tiler. Another use for subpixel resolution, i.e., doing antialiasing by subsampling is also considered. Using integer arithmetic in addition to subsampling is briefly discussed     

Rule-based cleanup of on-line English ink notes

Recently, many pen-based devices have enabled people to input digital ink naturally. Often, there is smear and correction when writing. This not only makes the document dirty and look unpleasant, but also affects the handwriting recognition when recognition is called for. As the first paper to address the ink cleanup problem, we present our ink cleanup system that removes the smear and correction, so that the document becomes cleaner and more legible and the handwriting recognition rate could also be improved. The algorithms are rule-based and are capable of dealing with the most common cases that may happen during writing, including self-overtracing of a single stroke, inter-overtracing between strokes, correction, touch-up, insertion and wrong writing order. Experimental results show that our system is effective in cleaning the ink note and is promising in increasing the recognition rate as well.     

Approximate Line Scan-Conversion and Antialiasing

This paper presents an approximate multiple segment line scan-conversion method — the Slope Table Method. The statistics show that the new method can increase the percentage of multiple segment lines (i.e., lines with more than one segment) in an N×N raster area from about 39% to more than 99%. In software implementation for scan-conversion and antialiasing of randomly generated lines, this method is on average more than 6 times faster than Gupta's antialiasing line algorithm. Compared with other line scan-conversion methods, the method may choose pixels which are not the closest to the line (i.e., error pixels). Here the paper demonstrates that the visual effect is acceptable in most applications with the error pixels.     

Binarization and cleanup of handwritten text from carbon copy medical form images

This paper presents a methodology for separating handwritten foreground pixels, from background pixels, in carbon copied medical forms. Comparisons between prior and proposed techniques are illustrated. This study involves the analysis of the New York State (NYS) Department of Health (DoH) Pre-Hospital Care Report (PCR) [Western Regional Emergency Medical Services, Bureau of Emergency Medical Services, New York State (NYS) Department of Health (DoH), Prehospital Care Report v4.] which is a standard form used in New York by all Basic and Advanced Life Support pre-hospital health care professionals to document patient status in the emergency environment. The forms suffer from extreme carbon mesh noise, varying handwriting pressure sensitivity issues, and smudging which are further complicated by the writing environment. Extraction of handwriting from these medical forms is a vital step in automating emergency medical health surveillance systems.     

维吾尔文手写体联机识别中延迟笔画处理方法

延迟笔画处理是维吾尔文联机手写体单词识别中的难点,样本数据格式为一串具有时序性的序列,造成字母主笔画和延迟笔画在序列位置上多半不连续,很大程度上增加了延迟笔画处理和单词识别的难度。为此,提出一种维吾尔文延迟笔画处理方法,其中包括延迟笔画查找与投影,实验结果证明该方法具有良好的效果,单词识别准确率达到93.71%。