首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 607 毫秒
1.
本文依据人的语音特征与指纹,血液一样,具有因人而异的个体特征的客观事实,论述了利用计算机在时域,频域,倒谱域以及线性预测等方面提取话者的语音特征的方法。为利用计算机语音识别技术,迅速捕获罪犯提供了一条实用有效的途径。  相似文献   

2.
提出了一种语音主观质量的客观评估算法,该算法在巴克谱的基础上计算原始语音与重建语音之间的失真度,并考虑了弱音帧与噪声帧的存在对语音质量评估的影响。文中同时给出了结合巴克谱失真和弱音与噪声帧比率的语音质量评估公式,并将计算结果与平均意见分(MOS)进行了比较。数值实验表明,本文提出的增强型巴克谱失真测度(IBSD)与MOS之间具有很强的相关性.能客观地评价出语音信号的主观质量,适用于各种语音编码、语音通信系统。  相似文献   

3.
几种无语音检测噪音估计方法的比较研究   总被引:1,自引:0,他引:1  
噪音谱的估计是谱相减方法中关键的一环。传统的噪声谱的估计是通过对输入语音作语音检测,区分出纯噪声段,根据噪声段的频谱估计出噪声谱。该方法的准确性局限于语音检测算法的性能,在信噪比较低时,性能下降很快。近年来人们提出了多种不用语音检测的噪声估计方法,这些方法不区分语音和非语音段,在每一帧都进行噪声谱的更新。评估了几种无语音检测的噪音估计方法,比较了它们用于谱相减时在语音识别中的性能,提出了一种新的基于能量聚类的无语音检测噪音估计方法,通过实验验证了它的优良性能。  相似文献   

4.
语音信号基音检测的现状及展望   总被引:17,自引:0,他引:17  
冯康  时慧琨 《微机发展》2004,14(3):95-98,101
基音检测是语音处理中的一个非常重要的问题,但由于影响基音检测的因素众多.使得基音周期的准确估计非常困难。文中阐述了短时自相关函数法、短时平均幅度差函数法、倒谱法、小波变换法等几种经典的基音检测方法.分析它们各自的优点及存在的不足,并在预处理.后处理、语音信号的产生模型、语音信号的个性特征、发音时的情感及力度等基音检测的各个环节上提出了一些看法,并就一些可能出现的突破口做了一些展望。  相似文献   

5.
基于Speech SDK的语音控制应用程序的设计与实现   总被引:19,自引:1,他引:19  
分析了微软Speech SDK5.1里语音应用程序接口(SAPI)的结构和工作原理,提出了语音控制应用程序的设计方法,并以“Z Z智能教学平台的语音识别接口”的设计为例,展示了这类系统的主框架和关键技术。  相似文献   

6.
本文详细讨论了传统声光报警器的更新换代产品,语音报警器的开发和研制,首先介绍了语音报警器所采用的方案和要实现的基本功能;然后介绍语音处理器及语音的固化、语音回放及闪光产生单元电路;最后讨论了语音报警器的结构以及程序设计。  相似文献   

7.
中等词汇的汉英语音翻译系统   总被引:1,自引:0,他引:1  
本文给出汉英语音翻译系统的组成,介绍了系统中连续汉语语音识别和汉英机器翻译的工作;我们已经在限定主题、中等词汇量的条件下实现了非特定人的连续语音识别,实现了汉英语音翻译实验演示系统。  相似文献   

8.
基于贝叶斯方法的鲁棒语音切分   总被引:1,自引:0,他引:1  
在基于隐马尔科夫模型的语音切分基础上,融合了不受噪声干扰的先验切分模型,提出了基于贝叶斯方法的语间切分方法。在贝叶斯切分方法的框架内,作者首先对语音序列进行了变换,将由切分点构成的序列变为由音节长度构成的序列。然后,假设音节长度序列符合一阶马尔科夫过程,经过归一化处理后,求出了切分的先验概率公式,得到了贝叶斯方法的切分模型。在噪声环境下的实验证明,由于切分模型独立于噪声,对在噪声环境下声学模型的失配提供了很好的补偿,使得语音切分的鲁棒性大大增加。  相似文献   

9.
本文提出了一种语音加密方法及其实现方案,利用人耳对声音相位变化不敏感的特性,将压缩后的语音信息插入到声音的高频区相位中,而人耳又听不出声音有所变化。该方法通过计算机模拟试验。  相似文献   

10.
介绍了语音识别的发展历史和国内外语音识别研究的现状,讨论了语音识别的几个基本问题和影响语音识别的因素,并分析了目前常用的语音识别的各种方法,指出了其优缺点,最后讨论了评价语音识别系统时应考虑的几个技术指标和将来语音处理的发展方向等。  相似文献   

11.
The new method of defuzzification of output parameters from the base of fuzzy rules for a Mamdani fuzzy controller is given in the paper. The peculiarity of the method is the usage of the universal equation for the area computation of the geometric shapes. During the realization of fuzzy inference linguistic terms, the structure changes from the triangular into a trapezoidal shape. That is why the universal equation is used. The method is limited and can be used only for the triangular and trapezoidal membership functions. Gaussian functions can also be used while modifying the proposed method. Traditional defuzzification models such as Middle of Maxima − MoM, First of Maxima − FoM, Last of Maxima − LoM, First of Suppport − FoS, Last of Support − LoS, Middle of Support − MoS, Center of Sums − CoS, Model of Height − MoH have a number of systematic errors: curse of dimensionality, partition of unity condition and absence of additivity. The above-mentioned methods can be seen as Center of Gravity − CoG, which has the same errors. These errors lead to the fact that accuracy of fuzzy systems decreases, because during the training root mean square error increases. One of the reasons that provokes the errors is that some of the activated fuzzy rules are excluded from the fuzzy inference. It is also possible to increase the accuracy of the fuzzy system through properties of continuity. The proposed method guarantees fulfilling of the property of continuity, as the intersection point of the adjustment linguistic terms equals 0.5 when a parametrized membership function is used. The causes of errors and a way to delete them are reviewed in the paper. The proposed method excludes errors which are inherent to the traditional and non- traditional models of defuzzification. Comparative analysis of the proposed method of defuzzification with traditional and non-traditional models shows its effectiveness.  相似文献   

12.
面向查询的多文档摘要技术有两个难点 第一,为了保证摘要与查询密切相关,容易造成摘要内容重复,不够全面;第二,原始查询难以完整描述查询意图,需进行查询扩展,而现有查询扩展方法多依赖于外部语义资源。针对以上问题,该文提出一种面向查询的多文档摘要方法,利用主题分析技术识别出当前主题下的子主题,综合考虑句子所在的子主题与查询的相关度以及子主题的重要度两方面因素来选择摘要句,并根据词语在子主题之间的共现信息,在不使用任何外部知识的情况下,进行查询扩展。在DUC2006评测语料上的实验结果表明,与Baseline系统相比,该系统取得了更高的ROUGE评价值,基于子主题的查询扩展方法则进一步提高了摘要的质量。  相似文献   

13.
针对复杂的具有周期性结构的织物瑕疵检测,提出一种基于结构相似性与模板校正的织物瑕疵检测方法。通过图案的周期性,得到图案单位模板大小,再对图像自动分割,同时应用基于模板校正的方法以减少晶格之间未对准的影响,并构建均值模板。通过计算所有晶格间的结构相似性,并将相似关系通过传递闭包的方式得到等价关系,再进行晶格间的聚类。之后通过阈值分割方法,完成瑕疵区域的检测。通过实验表明,改进后的算法检测效果较好,本文算法显著提高了样本的查准率。  相似文献   

14.
15.
Measurements of spring phenological dates in boreal regions using NDVI can be affected by snowmelt. This impacts the analysis of interannual variations in phenology and the estimates of annual carbon fluxes. For these two objectives, snowmelt effect must be removed from the phenological detection. We propose a methodology for determining the date of onset of greening in the 1982-2004 period using SPOT-VEGETATION (VGT) and NOAA Advanced Very High Resolution Radiometer (AVHRR) data. From 1998 onwards, the date of onset of greening is taken as the date at which the Normalized Difference Water Index (NDWI), calculated from SPOT-VGT near and short-wave infrared bands, starts increasing. This index decreases with snowmelt but increases with vegetation greening. For the 1982-2001 period, the date of onset of greening is the date at which AVHRR-NDVI equals a pixel specific threshold (PST), determined using the results of the NDWI method in the years common to the two datasets. The methods are validated using in situ measurements of the dates of leaf appearance. RMSE of 6.7 and 7.8 days, respectively, is found using NDWI-VGT and PST-NOAA methodologies, and the difference between the two methodologies in the common years is small. Very importantly, the dates are not biased. The interannual variations of the 23-year spring phenology dataset on the study area in northern Eurasia are analysed. In average over the study area, an advance of 8 days and a delay of 3.6 days are, respectively, found over the periods 1982-1991 and 1993-2004. These results confirm and complete previous studies about the greening trend, remove the uncertainty due to snow, and may improve carbon budget calculations.  相似文献   

16.
This paper deals with the question: What are the criteria that an adequate theory of computation has to meet? (1) Smith’s answer: it has to meet the empirical criterion (i.e. doing justice to computational practice), the conceptual criterion (i.e. explaining all the underlying concepts) and the cognitive criterion (i.e. providing solid grounds for computationalism). (2) Piccinini’s answer: it has to meet the objectivity criterion (i.e. identifying computation as a matter of fact), the explanation criterion (i.e. explaining the computer’s behaviour), the right things compute criterion, the miscomputation criterion (i.e. accounting for malfunctions), the taxonomy criterion (i.e. distinguishing between different classes of computers) and the empirical criterion. (3) Von Neumann’s answer: it has to meet the precision and reliability of computers criterion, the single error criterion (i.e. addressing the impacts of errors) and the distinction between analogue and digital computers criterion. (4) “Everything” computes answer: it has to meet the implementation theory criterion by properly explaining the notion of implementation.  相似文献   

17.
CCD camera modeling and simulation   总被引:2,自引:0,他引:2  
In this paper we propose a modeling of an acquisition line made up of a CCD camera, a lens and a frame grabber card. The purpose of this modeling is to simulate the acquisition process in order to obtain images of virtual objects. The response time has to be short enough to permit interactive simulation. All the stages are modelised: in the first phase, we present a geometric model which supplies a point to point transformation that provides, for a space point in the camera field, the corresponding point on the plane of the CCD sensor. The second phase consists of modeling the discrete space which implies passing from the continous known object view to a discrete image, in accordance with the different orgin of the contrast loss. In the third phase, the video signal is reconstituted in order to be sampled by the frame grabber card. The practical results are close to reality when compared to image processing. This tool makes it possible to obtain a short computation time simulation of a vision sensor. This enables interactivity either with the user or with software for the design/simulation of an industrial workshop equipped with a vision system. It makes testing possible and validates the choice of sensor placement and image processing and analysis. Thanks to this simulation tool, we can control perfectly the position of the object image placed under the camera and in this way, we can characterise the performance of subpixel accuracy determining methods for object positioning.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
Multisim8是一款优秀仿真软件,使用该软件可对电路进行各种参数分析。我们在享受其便利的同时,也遇到因缺少元器件导致电路仿真无法进行的阻力。解决此问题的方法就是为元件建立仿真模型并新建或扩充已有的元器件库。在不熟悉Spice编程原理的情况下,我们可通过相关网址查找到元件厂商提供的元件模型,利用模型导入的方法来建立需要的新元件。通过对新元件应用电路的仿真分析,新元件完全符合要求。在此基础上,使用元件的导入与导出功能还可对新元件进行文件备份并实现新元件在不同用户间的资源共享。  相似文献   

20.
基于覆盖的粗集是推广经典粗集理论的方法之一,有基于元素、基于粒和基于子系统的3类定义上下近似的途径,以往大多数的文献往往从基于元素的角度出发进行定义。为了研究基于粒的近似算子特别是下近似算子的性质,借鉴格论中既约元、可约元等概念,提出了集族约简的概念。从集族约简出发,探讨了集族等价的概念与性质,并设计了集族约简的算法,得到了两个集族等价是两个集族生成相同的下近似运算的充要条件这一结果,为进一步开展一般二元关系下基于粒的近似算子的公理化方法的研究做了初步的理论方面的准备工作。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号