基于小波域图像不变矩的图纸一致性检测

审图系统中，需要对报送的工程图纸和已有的电子图纸进行一致性检测。为此，提出了基于小波变换和图像不变矩的图纸一致性检测算法。该算法首先利用仿射变换对预处理后的工程图纸进行图纸配准，然后利用小波变换对扫描图纸和电子图纸实现小波分解，简化比对的计算量，并利用图像不变矩的平移、尺度和旋转不变特性，作为图纸比对的准则。实验结果表明，此算法能很好地实现审图系统中图纸的一致性检测。     

给数据库增添图形图像功能(三)——一种实用的数据库图像软件的设计

本文介绍了在FoxBASE或dBASE环境下显示PCX图像文件的方法。给出了用C语言实现的程序。同时还介绍了PCX图像文件的格式以及如何对该文件进行解码。     

扫描技术继续生存

我们有如此多的信息是以打印件存储的。即使电子备份业已存在，我们要面对的仍然不止是电子文件而已，IT人说要实现磁带存储太难了，电力公司不会以简便的电子格式把帐单发给你。我喜欢一切都是电子版的，但情况不会如此。与此同时，我们看看如何使现有的扫描技术为你所用。     

寄书写心曲——电子书制作

如今，电子书已经不再是陌生词语，它是一种电子读物，它是将原始的html、txt、doc、图像文件等打包制作而成的一个独立的文件。     

宁波北仑的城市规划档案管理信息系统

随着办公自动化的进一步发展和深化，特别是电子计算机和通信技术相结合形成了信息技术产业，过去用纸墨、照像等形成和传递的政府机关公文以及图书、图纸、图形、图像、文献资料、商业信息等，都可以用电子计算机进行，由此而产生了电子公文、电子图书、电子图形图像、电子文献资料等，这些都是属于电子文件。其中具有档案保存价值的电子文件，归档后即形成电子档案。     

应用光盘推广和深化CAD技术的应用 促进图档管理的现代化

工程图纸是工程技术人员描述设计对象，表达设计思想的主要工具，工程图纸记录了广大工程技术人员从事建设的辛勤劳动，凝聚着他们非常宝贵的技术知识和工作经验。这些图纸作为档案保存，是对设计人员智慧的积累，是保证企业持续发展的很重要的环节。随着现代电子信息技术的发展，设计手段的现代化，图档以电子文件形式出现，越来越多的企业面临着新的挑战。随着CAD技术的普及应用，越来越多的工程、产品图纸存档以及管理制度应作出相应的变革和调整。应用光盘存储技术是CAD技术发展的必然。采用CAD技术和光盘存储工程图纸等技术资料（…     

基于OCR 技术的政府机关制度文件文字内容识别研究

制度及规范性文件是内部审计人员开展现场审计工作以及审计发现问题定性时的重要依据,经常需要反复检索查阅,但由于政府机关的电子制度文件主要以纸质扫描图片或电子公文系统生成的pdf文件等形式保存,无法进行全文检索。为此,笔者运用Tesseract-OCR开源OCR引擎,将图片和pdf文件中的文字内容识别并提取出来,为实现制度内容的全文检索奠定了基础。     

XBASE数据库图像信息自动提取转换

分析了各个版本XBASE数据库文件和图像文件的结构，提出了XBASE数据库图像信息自动导出转换的处理方法，提高了数据库转换工作的效率，解决了无法转换XBASE备注文件中的图像数据，文中还对实际应用中部分环节进行了注意事项说明，该方法具有很强的可操作性和实用性。     

基于二次栅格扫描的无线传感器网络定位算法

为了提高无线传感器网络的定位精度,在栅格扫描算法的基础上提出了一种基于二次栅格扫描的无线传感器网络定位算法.利用未知节点与两跳范围内的锚节点的连通性约束信息,在近节点对未知节点进行栅格扫描得到其初始位置估计的基础上,引入远节点对未知节点再次进行栅格扫描,从而提高定位精度.算法增加了远节点栅格扫描的计算量,但不需要额外地增加节点的硬件功能.仿真结果表明,与仅利用近节点的栅格扫描算法相比,该算法在锚节点密度增大的过程中可以更快地提高定位精度.     

信息系统中电子档案的实现及应用

为了管理业务办公系统中所需的文档资料,解决电子档案的录入、存储和访问问题,提出基于扫描及非结构化文档管理的实用方案。该方案先扫描原始凭据并保存在PDF文件中,然后用FIP批量上传这些档案,客户端以FIP文件下我的方式查询电子档案。     

Document representation and its application to page decomposition

Transforming a paper document to its electronic version in a form suitable for efficient storage, retrieval, and interpretation continues to be a challenging problem. An efficient representation scheme for document images is necessary to solve this problem. Document representation involves techniques of thresholding, skew detection, geometric layout analysis, and logical layout analysis. The derived representation can then be used in document storage and retrieval. Page segmentation is an important stage in representing document images obtained by scanning journal pages. The performance of a document understanding system greatly depends on the correctness of page segmentation and labeling of different regions such as text, tables, images, drawings, and rulers. We use the traditional bottom-up approach based on the connected component extraction to efficiently implement page segmentation and region identification. A new document model which preserves top-down generation information is proposed based on which a document is logically represented for interactive editing, storage, retrieval, transfer, and logical analysis. Our algorithm has a high accuracy and takes approximately 1.4 seconds on a SGI Indy workstation for model creation, including orientation estimation, segmentation, and labeling (text, table, image, drawing, and ruler) for a 2550×3300 image of a typical journal page scanned at 300 dpi. This method is applicable to documents from various technical journals and can accommodate moderate amounts of skew and noise     

扫描图象曲线轮廊关键点的提取及其处理

针对工程图样中线段的识别和提取问题,提出了一种提取扫描图象曲线轮廊关键点的算法和相应的提取条件准则,该算法可自动逐行检测扫描行中的黑游程,当相继行中的黑游程满足一定的条件准则时,即可提取出相应的黑游程边界点,并形成关键点,依据这些关键点,利用B样条曲线理论来拟合曲线,最终即可实现对图象曲线的提取,该算法不仅速度快,抗噪声性能强,且提取识别也到得了满意的效果。     

一种基于迭代阈值法的身份证图像二值化算法研究

针对身份证扫描图像受激光防伪阴影网格线影响较大的特点,对图像二值化的方法进行了深入分析和研究．提出了一种基于像素邻域特征的迭代阈值方法。该算法模型简单、易于实现．能滤除噪声、使字符笔划清晰地从背景中分割出来．获得了较好的二值化效果。     

The Indexing and Retrieval of Document Images: A Survey

The economic feasibility of maintaining large data bases of document images has created a tremendous demand for robust ways to access and manipulate the information these images contain. In an attempt to move toward a paperless office, large quantities of printed documents are often scanned and archived as images, without adequate index information. One way to provide traditional data-base indexing and retrieval capabilities is to fully convert the document to an electronic representation which can be indexed automatically. Unfortunately, there are many factors which prohibit complete conversion including high cost, low document quality, and the fact that many nontext components cannot be adequately represented in a converted form. In such cases, it can be advantageous to maintain a copy of and use the document in image form. In this paper, we provide a survey of methods developed by researchers to access and manipulate document images without the need for complete and accurate conversion. We briefly discuss traditional text indexing techniques on imperfect data and the retrieval of partially converted documents. This is followed by a more comprehensive review of techniques for the direct characterization, manipulation, and retrieval, of images of documents containing text, graphics, and scene images.     

基于SFS的方法恢复扫描文件图像

从原装订本上扫描文件页面往往会导致扫描图像扭曲的情况。该文简要先介绍了SFS方法及分类。然后提出从技术的角度看利用SFS重构扫描图像这一问题。在现实环境中扫描图像有如下特征:1)一个靠近的移动光源;2)Lambertian式光反射;3)文件偏斜。然后利用基于去除灰度和去除变形模式的方法来恢复扫描文件图像。用以重构书曲面的图像,恢复扫描图像。     

基于SFS的方法恢复扫描文件图像

从原装订本上扫描文件页面往往会导致扫描图像扭曲的情况。该文简要先介绍了SFS方法及分类。然后提出从技术的角度看利用SFS重构扫描图像这一问题。在现实环境中扫描图像有如下特征：1）一个靠近的移动光源;2）Lambertian式光反射;3）文件偏斜。然后利用基于去除灰度和去除变形模式的方法来恢复扫描文件图像。用以重构书曲面的图像,恢复扫描图像。     

An automatic closed-loop methodology for generating charactergroundtruth for scanned documents

Character groundtruth for real, scanned document images is crucial for evaluating the performance of OCR systems, training OCR algorithms, and validating document degradation models. Unfortunately, manual collection of accurate groundtruth for characters in a real (scanned) document image is not practical because (i) accuracy in delineating groundtruth character bounding boxes is not high enough, (ii) it is extremely laborious and time consuming, and (iii) the manual labor required for this task is prohibitively expensive. Ee describe a closed-loop methodology for collecting very accurate groundtruth for scanned documents. We first create ideal documents using a typesetting language. Next we create the groundtruth for the ideal document. The ideal document is then printed, photocopied and then scanned. A registration algorithm estimates the global geometric transformation and then performs a robust local bitmap match to register the ideal document image to the scanned document image. Finally, groundtruth associated with the ideal document image is transformed using the estimated geometric transformation to create the groundtruth for the scanned document image. This methodology is very general and can be used for creating groundtruth for documents in typeset in any language, layout, font, and style. We have demonstrated the method by generating groundtruth for English, Hindi, and FAX document images. The cost of creating groundtruth using our methodology is minimal. If character, word or zone groundtruth is available for any real document, the registration algorithm can be used to generate the corresponding groundtruth for a rescanned version of the document     

Inertia‐based Fast Vectorization of Line Drawings

Image vectorisation is a fundamental method in graphic design and is one of the tools allowing to transfer artist work into computer graphics. The existing methods are based mainly on segmentation, or they analyse every image pixel; thus, they are relatively slow. We introduce a novel method for fast line drawing image vectorisation, based on a multi‐scale second derivative detector accelerated by the summed‐area table and an auxiliary grid. Image is scanned initially along the grid lines, and nodes are added to improve accuracy. Applying inertia in the line tracing allows for better junction mapping in a single pass. Our method is dedicated to grey‐scale sketches and line drawings. It works efficiently regardless of the thickness of the line or its shading. Experiments show it is more than two orders of magnitude faster than the existing methods, not sacrificing accuracy.     

Skew Correction of Document Images Using Interline Cross-Correlation

An efficient algorithm is presented in this paper for correcting skew of text lines in scanned document images. In this method, the cross-correlation between two lines in the image with a fixed distance is calculated. The correlation functions for all pairs of lines in the image are accumulated. The shift for which the accumulated cross-correlation function takes the maximum is then used for determining the skew angle. The image is rotated in the opposite direction for skew correction. The correlation function can be calculated without multiplications for binary images, thus the algorithm can be very efficiently implemented. The method can be used directly for gray-scale and color images as well as binary images. It has been tested on scanned document images with good results.