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61.
Tsung-Han Tsai Author Vitae Author Vitae Chih-Lun Fang Author Vitae 《Pattern recognition》2009,42(7):1496-1510
In video indexing and summarization, videotext is the very compact and accurate information. Most videotext detection and extraction methods only deal with the static videotext on video frames. Few methods can handle motion videotext efficiently since motion videotext is hardly extracted well. In this paper, we propose a two-directional videotext extractor, called 2DVTE. It is developed as an integrated system to detect, localize and extract the scrolling videotexts. First, the detection method is carried out by edge information to classify regions into text and non-text regions. Second, referring to the localization on scrolling videotext, we propose the two-dimensional projection profile method with horizontal and vertical edge map information. Considering the characteristics of Chinese text, the vertical edge map is used to localize the possible text region and horizontal edge map is used to refine the text region. Third, the extraction method consists of dual mode adaptive thresholding and multi-seed filling algorithm. In the dual mode adaptive thresholding, it produces the non-rectangle pattern to divide the background and foreground more precisely. Referring to the multi-seed filling algorithm, it is based on the consideration of the minimum and maximum length and four directions of the stroke while the previous method only considers the minimum length and two directions of the stroke. With this multi-seed exploitation on strokes, precise seeds are obtained to produce more sophisticated videotext. Considering high throughput and the low complexity issue, we can achieve a real-time system on detecting, localizing, and extracting the scrolling videotexts with only one frame usage instead of multi-frame integration in other literatures. According to the experiment results on various video sequences, all of the horizontal and vertical scrolling videotexts can be extracted precisely. We also make comparisons with other methods. In our analysis, the performance of our algorithm is superior to other existing methods in speed and quality. 相似文献
62.
At present,the automatic extraction of urban built\|up area is still a problem.Taking Shanghai city as an example,this research uses the binary image,which was derived from an IBI(index\|based built\|up index)image,as the geographical cellular automaton initial input data.This was then imported to the extended cellular automata model for further processing.After a series of processing such as thresholding,corrosion and connectivity test,the urban built\|up area was simulated and can be extracted.Based on this method,the urban built\|up area of Shanghai in five different years between 1987 and 2015 was extracted using multi\|temporal Landsat images of Shanghai.In addition,the urban growth intensity index,the concentric buffers analysis and radar chart analysis were calculated and used to analysis spatiotemporal pattern of Shanghai urban expansion in the 28 study years.The result shows that the built\|up area of Shanghai was expanded from 195 km2 in 1987 to 1759 km2 in 2015,which is eight times as large as that in 1987.In the period between 1987 and 2002,the urban built\|up area expanded mainly along the North\|South axis of the Huangpu River.However,after 2002 the expansion rate was increased more quickly,and the direction of the expansion was shifted to an east to west direction.Generally speaking,Shanghai has experienced a rapid urban expansion in the recent three decades. 相似文献
63.
This article described the way to extract information of copper and lead anomaly in high vegetation coverage area through a case study from the Datuanbao copper ore deposit and its environs,Jiangcheng,Yunnan Province.Principal component analysis,false color composite,stretch Histogram and supervise classification etc were analyzed in the remote sensing images using ENVI4.6 software.It is suggested that the linear structure,which is delineated by convolution filter and morphological analysis method,is characterized by statistical self-similarity and fractal geometry.It is found that the high value of fractal dimension is roughly coincident with the copper and lead anomaly of vegetation by the comparison between contour maps of plant geochemical anomaly and fractal dimensions,which is calculated by box-counting.As a matter of fact,80 percent of copper and lead deposits or occurrences are located in areas of high value of fractal dimension and vegetation anomaly.By the comprehensive analysis of stratigraphy,igneous rocks,copper and lead mineralizations,fractal dimension of linear structures and vegetation anomaly from remote sensing,nine exploration targets with three levels of probabilities are figured out. 相似文献
64.
根据可变精度粗糙集的R-上、下分布约简算法的优势,结合概念格形式背景的特点,将二者有机地结合,提出了基于变精度粗糙集的概念格约减算法。分析了变精度粗糙集模型中的R值的选取算法、可辨识矩阵属性约简,以及传统算法中存在的问题,并进行了改进。最后,为了验证改进后算法的有效性,设计了基于变精度粗糙集的概念格生成系统,通过一个实例演示了构造概念格的整个过程,并通过实验证明了算法的有效性。 相似文献
65.
鲁棒的多体印刷英文识别系统的实现 总被引:6,自引:1,他引:5
文章讨论了设计一个实用的多体英文识别系统中解决的主要问题。该系统能识别多达260种字体,包括斜体和黑体等字体,对训练集的识别率达到99%,对实际文本测试的错误率比TH-OCR2000低56%。文章详细阐述了文本行字切分,特征提取和分类器设计,以及后处理所使用的常用技术,对各种技术的特点进行了分析和比较,并提出了一些新的技术。文章对于OCR系统的设计具有一定的指导意义。 相似文献
66.
基于Client/Server模式的智能抽题算法 总被引:4,自引:0,他引:4
文章介绍了一种应用于Client/Server模式的计算机辅助测试系统中的智能抽题算法。该算法采用抽题脚本动态获取题目信息,运用优化替换技术对抽取的脚本草稿进行替换修正,具有抽题快捷、网络传输量小、对数据库的完备性要求较低、通用性较强的优点。 相似文献
67.
刘军 《数字社区&智能家居》2007,1(2):451-452
为了提取网页中的主题信息,提出了一种基于支持向量机(SVM)的网页主题信息提取算法.该算法首先将整个网页划分成多个不同的信息块;然后根据信息块中的文本、图片、链接及信息块的位置建立其特征向量;通过训练得到SVM的最优分类函数;最后通过最优分类函数的符号判断给定的信息块是否是主题信息.封闭式测试中,指标precision和gain在最高时达到98%和96%;开放式测试中,两指标分别为92%和87%. 相似文献
68.
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70.
梯形波脉冲筛板萃取柱传质性能 总被引:1,自引:0,他引:1
本文以UO_2(NO_3)_2—30%TBP(KO)为实验体系,进行了梯形波脉冲筛板柱传质性能的研究。实验中测量了两组分的两相稳态浓度剖面共13组,以扩散模型为基础,求得了梯形波脉冲柱的“真实”传质单元高度HTU_(ox),分散单元高度HDU及表观传质单元高度HTU_(oxp)。通过对实验结果进行分析,选择出了适于本实验体系的较好的操作条件。 相似文献