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1.
提出了一种基于关键帧颜色和纹理特征的视频拷贝检测方法。首先通过子片段方法提取视频的关键帧,然后将关键帧分成3个子块,提取每个子块的三维量化颜色直方图,通过直方图相交法来进行颜色特征的匹配。对检索得到的结果视频关键帧进行纹理特征提取,通过其灰度共生矩阵的角二阶矩和熵来表征其纹理特征,纹理特征的匹配可进一步过滤不相关的视频。实验结果表明,该方法效果好、稳健性强且可应用于多种类型的视频。  相似文献   

2.
提出了一种基于关键帧颜色和纹理特征的视频拷贝检测方法.首先通过子片段方法提取视频的关键帧,然后将关键帧分成3个子块,提取每个子块的三维量化颜色直方图,通过直方图相交法来进行颜色特征的匹配.对检索得到的结果视频关键帧进行纹理特征提取,通过其灰度共生矩阵的角二阶矩和熵来表征其纹理特征,纹理特征的匹配可进一步过滤不相关的视频.实验结果表明,该方法效果好、稳健性强且可应用于多种类型的视频.  相似文献   

3.
综合利用了图像的颜色、形状和纹理特征,实现了对视频关键帧进行基于内容的检索。首先研究关键帧的选取、特征匹配等问题,再从视频处理的层次化结构的底层分析入手,构建了视频的连续帧图像序列,运用时间自适应检测法对镜头的关键帧进行了选取,建立了关键帧图像数据库。实验结果证明该方法性能良好。  相似文献   

4.
毋立芳  赵宽  简萌  王向东 《信号处理》2019,35(11):1871-1879
关键帧检测是有效的视频内容分析的关键环节。常用的基于手工特征的方法运行效率高但很难有效表征关键帧特征,因而性能不好。基于深度特征的方法因为网络结构复杂,导致效率不高。在体育比赛类视频中,关键帧常为比赛转播中镜头变化的最后一帧。但广播视频中除了包含比赛视频还包括很多其他类型的镜头如中场休息、渐变镜头等。因此检测最后一帧包含很多比赛无关内容。针对这一问题,本文提出了一种手工特征与深度特征相结合的视频关键帧检测方法。首先基于颜色直方图特征进行镜头边界检测获取最后一帧。进一步基于直方图相似性提出一种类似聚类的方法得到候选关键帧。最后,基于深度神经网络对候选关键帧进行分类,得到真正的关键帧。在冰壶比赛视频和篮球比赛视频上的对比实验结果表明,相对于传统的背景差分法、光流法等,本文提出方法能够快速、可靠地提取关键帧。   相似文献   

5.
基于颜色直方图的图像检索技术   总被引:18,自引:0,他引:18  
讨论了基于颜色直方图的图像检索中颜色空间和直方图距离的选择问题,提出了利用颜色直方图来检索图像的一般框架,建立了基于两种颜色空间(RGB和HSV)和四种直方图距离共八种图像检索算法,并且采用了两种客观评价标准对所建立算法的有效性进行评价。结果证明,在基于颜色直方图的应用中,HSV空间比RGB空间更有效,EMD距离在所有四种距离量度中性能较好,但计算量稍大,与EMD距离相比,虽交集距离性能稍有不足,但所需计算量较小。  相似文献   

6.
胡秀  王书爱 《激光杂志》2024,(3):145-149
为保证激光视频图像检索结果中不存在重复性冗余图像,提出了基于互信息量均方差提取关键帧的激光视频图像检索方法。基于互信息量均方差的关键帧提取方法,以激光视频图像颜色的互信息量均方差最大化,为激光视频图像关键帧的聚类中心设置标准,以此聚类提取不重复的视频图像关键帧;通过基于关键帧的激光视频图像检索方法,将所提取关键帧作为激光视频图像检索的核心判断内容,提取与所需图像关键帧相似度显著的激光视频图像,完成激光视频图像检索。实验结果显示:此方法使用后,提取的激光视频图像关键帧冗余度仅有0.01,激光视频图像检索结果的MAP指标测试值高达0.98,检索结果中不存在重复性冗余图像。  相似文献   

7.
基于组合相似性的视频检索   总被引:2,自引:0,他引:2  
该文研究基于镜头的视频检索问题,提出了一种新的基于组合相似性的镜头相似性度量方法。首先把镜头看成由帧序列组成的一个组合,镜头的相似性通过帧组合的相似性来度量。其次通过用一个非线性映射,把帧组合所在的空间映射到一个高维空间,在这个空间中,假设帧组合服从正态分布,利用核方法,抽取出关键帧序列,并计算出两个正态分布之间的概率距离,这个距离表明了帧组合的相似程度,从而得到两个镜头之间的相似性。最后将这种方法应用于基于镜头的视频检索中,实验表明在相同条件下,基于该方法的检索效果明显优于传统的欧式距离和直方图交方法。  相似文献   

8.
亓玉娇  杜海清 《电视技术》2012,36(21):37-39,108
视频镜头分割是视频检索和视频分类等应用的关键步骤,因此提出一种基于颜色直方图和灰度熵的镜头检测算法。该方法以HSV颜色直方图和图像的灰度熵为特征,计算视频相邻两图像帧的相似度,从而判断出是否发生了镜头变换。实验证明,该方法能准确检测出视频的突变镜头,对渐变镜头也有理想的检测效果。  相似文献   

9.
关键帧的提取是视频数据结构化的一部分,在获得关键帧之后就可以进入基于内容的图像检索阶段,实现基于内容的视频检索。本文提出了一种在镜头边界检测之后再进行视频帧聚类的方法来提取关键帧。聚类形成了数据更小的子镜头,最后从子镜头中选择与聚类中心距离最小的一帧作为关键帧。最后,通过仿真实验表明该方法能够快速有效地提取出视频关键帧。  相似文献   

10.
基于压缩传感和EMD距离的视频镜头关键帧提取   总被引:2,自引:2,他引:0  
潘磊  束鑫  程科 《电视技术》2015,39(17):5-8
关键帧提取是视频内容分析与检索技术的核心问题。提出一种基于压缩传感和EMD距离的关键帧提取方法,首先构造一个符合有限等距性质的稀疏矩阵,将帧高维特征投影到低维空间,然后通过计算帧低维特征之间的调节余弦相似度完成子镜头分割。在各子镜头中,利用EMD距离计算帧与子镜头中心的差异,并选择差异最小值所对应的帧作为该子镜头的关键帧。实验结果表明,该方法提取的关键帧能够对视频内容进行准确的描述。  相似文献   

11.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

12.
IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…  相似文献   

13.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

14.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

15.
A doping system consisting of NPB and PVK is employed as a composite hole transporting layer (CHTL). By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK : NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK : NPB at 1:3.  相似文献   

16.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

17.
Due to variable symbol length of digital pulse interval modulation(DPIM), it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation(FDPIM) method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.  相似文献   

18.
It is a key problem to accurately calculate beam spots' center of measuring the warp by using a collimated laser. A new method, named double geometrical center method (DGCM), is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device (CCD) is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What's more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.  相似文献   

19.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

20.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

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