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1.
基于视频时空相关性的帧内预测模式抉择   总被引:1,自引:1,他引:0  
提出了一种帧内预测模式抉择方法,利用视频图像的时间相关性和空间相关性,选择部分预测模式对图像块进行帧内预测处理和编码,减少编码的计算复杂度,保持其原有的编码效率。同时提出了一种复杂度分级方法,通过准确控制帧内预测的复杂度,以匹配通信终端有限的计算资源。该方法在AVS-M平台中进行了验证。  相似文献   

2.
为实现复杂度可调的视频图像帧内预测方式,提出了一种预测模式选择策略,结合统计特性和图像相关性,自适应控制计算复杂度.实验结果表明,该策略实现了计算复杂度的可调性以匹配计算资源,同时基本保持与全模式搜索方法相当的编码效率.  相似文献   

3.
H.264中采用的率失真优化技术虽然提高了编码效率,但也使计算复杂度增加,影响编码的实时实现。针对这一问题,通过分析H.264中计算复杂度较高的帧内预测模式选择部分,提出一种新的帧内预测模式选择算法。根据模糊隶属度函数预先判断宏块类型,从Intra_4×4和Intra_16×16两种预测模式中选择一种,并通过判断4×4块的纹理方向,减少候选预测模式的数量。实验结果表明,在保持图像性能和码率基本不变的情况下,该算法能有效提高H.264的编码速度,有利于实时应用。  相似文献   

4.
高效视频编码(High Efficiency Video Coding,HEVC)相较于H.264/AVC,帧内预测模式有35种,编码性能得到提高的同时也引起了算法复杂度的增加,本文提出了一种基于Canny彩色算子的快速帧内预测模式选择算法。该算法基于图像物理边缘的梯度方向提前分析预测块(Prediction Unites,PU)的方向,预先确定帧内预测的模式,避免算法遍历35种帧内预测模式。实验结果表明,该算法能够有效地降低帧内编码的复杂度,算法编码时间平均减少23.36%而仅损失0.69%的BD-Rate,且率失真性能良好。  相似文献   

5.
我国自主研究的音视频编码标准AVS3在AVS2的基础上引入了许多新技术,极大地提高了编码效率,同时提升了编码时间复杂度.为了推进AVS3编码标准的商用,必须研究降低编码时间复杂度,力求达到实时编码.为此,从图像频域特征角度提出一种基于图像DCT系数的帧内预测模式选择快速算法,在DCT系数反映出的图像纹理角度基础上结合统计算法预测得出当前PU块的纹理角度,从而减少帧内预测过程中的预测模式遍历.实验结果表明,本算法能带来平均39%的时间复杂度降低,且在高分辨率和纹理复杂的情况下综合性能更优,时间复杂度最高降低46%.  相似文献   

6.
针对在降低H.264视频编码复杂度方面提出的一种有效的4×4帧内预测模式判决方法。研究发现,在基于变换域的帧内预测模式下,当一个块的局部边缘方向一致时,可以得到一种很好的预测,由此可以滤除大部分帧内模式。通过滤除大部分帧内模式,只需考虑剩余具有较高概率的4×4帧内预测模式,对于这些模式需要进行率失真优化处理。仿真结果表明,本判决方法在保证图像质量和压缩比不变的情况下,能够使计算量大大降低。  相似文献   

7.
适用于H.264/AVC的快速帧内预测算法   总被引:1,自引:0,他引:1       下载免费PDF全文
宋建斌  李波  李炜  吴波 《电子学报》2007,35(4):668-672
帧内预测算法极大地提高了I帧的压缩比率,但极高的计算复杂度与视频系统中计算资源有限、应用环境实时性要求高形成矛盾.本文提出了帧内预测快速算法,根据图像复杂程度进行块尺寸的选择,对于4×4块,利用环形滑动窗口动态缩小预测模式选择范围,定义简化的块匹配准则并采用计算及时终止策略.实验证明,在保持恢复图像质量几乎不降的同时,速度能提高到两倍多.快速算法具有额外计算量小,提速效果明显等特点.  相似文献   

8.
H.264/AVC标准引入RDO技术计算帧内预测最优模式,提高编码效率,但同时RDO技术的引入极大提升编码端的计算复杂度.提出了一种针对帧内预测4×4亮度块的快速模式选择算法,该算法利用亮度块SATD值与RDO技术间的相关性,优化原有算法.实验结果表明,算法能在基本不影响图像原有质量的情况下,较大程度减少编码H.264序列所需时间.  相似文献   

9.
一种新的H.264/AVC帧内模式快速选择算法   总被引:2,自引:2,他引:0  
利用改进的模糊积分准则提前对宏块的类型进行判定,实现Intra_4×4和Intra_16×16模式的快速选择,对于Intra_4×4模式,采用改进的平方梯度法估计块的纹理方向,从而排除可能性小的预测模式,提高帧内编码速度.试验表明该算法在基本保持编码性能的同时,可显著降低帧内预测的复杂度.  相似文献   

10.
H.264/AVC帧内预测技术采用率失真优化策略进行最优化编码模式选择,提高了I帧的编码效率,但同时也提高了计算复杂度。本文提出了一种帧内预测模式的快速选择算法,基于亮度块的方向特性,通过一些复杂度不大的计算,选择少数几个可能性较大的预测模式进行率失真代价计算,得到最佳亮度预测模式,并以 计算代替率失真代价计算选择最佳色度预测模式,降低了计算复杂度,提高了编码速度。实验结果表明,本文提出的算法在保证图像质量的同时,编码时间平均降低了48%,而码率增加很小。  相似文献   

11.
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   

12.
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   

13.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

16.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  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.
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   

20.
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   

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