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101.
102.
研究了如何利用GPU来加速视频解码,概述了MPEG-2视频解码的系统框架,论述了MPEG-2视频解码在Linux下以XvMC(X video motion compensation)为API并基于通用可编程GPU的实现过程,重点讨论了MPEG-2视频解码中IDCT(inverse discrete cosine transform)和运动补偿的实现,提出了新的优化算法.MPEG-2视频解码算法具有一定的通用性,实验结果表明,与传统的解码方式相比,该解码器不仅能加速视频解码,还能有效降低CPU的利用率和电脑的功耗. 相似文献
103.
光纤陀螺输入轴失准角温度补偿研究 总被引:2,自引:0,他引:2
提高温度特性是光纤陀螺仪工程化的一个难题,温度补偿是解决该问题的一种有效方法。光纤陀螺与温度相关误差项主要为零漂和标度因数,输入轴失准角也是影响光纤陀螺应用的一个重要误差项。在大量试验的基础上,分析了光纤陀螺输入轴失准角误差产生机理,采用多项式拟合方法建立了输入轴失准角误差全温模型,对多套光纤陀螺进行了全温补偿。试验结果表明,输入轴失准角补偿前全温变化在2?10-3rad数量级,补偿后全温变化小于3?10-4rad,精度提高了近一个数量级,大大提高了光纤陀螺仪的全温性能。 相似文献
104.
Active contours with selective local or global segmentation: A new formulation and level set method 总被引:4,自引:0,他引:4
A novel region-based active contour model (ACM) is proposed in this paper. It is implemented with a special processing named Selective Binary and Gaussian Filtering RegularizedLevel Set(SBGFRLS) method, which first selectively penalizes the level set function to be binary, and then uses a Gaussian smoothing kernel to regularize it. The advantages of our method are as follows. First, a new region-based signed pressure force (SPF) function is proposed, which can efficiently stop the contours at weak or blurred edges. Second, the exterior and interior boundaries can be automatically detected with the initial contour being anywhere in the image. Third, the proposed ACM with SBGFRLS has the property of selective local or global segmentation. It can segment not only the desired object but also the other objects. Fourth, the level set function can be easily initialized with a binary function, which is more efficient to construct than the widely used signed distance function (SDF). The computational cost for traditional re-initialization can also be reduced. Finally, the proposed algorithm can be efficiently implemented by the simple finite difference scheme. Experiments on synthetic and real images demonstrate the advantages of the proposed method over geodesic active contours (GAC) and Chan–Vese (C–V) active contours in terms of both efficiency and accuracy. 相似文献
105.
Jose Gonzalez-Mora Fernando De la Torre Nicolas Guil Emilio L. Zapata 《Image and vision computing》2010
Over the last decade 3D face models have been extensively used in many applications such as face recognition, facial animation and facial expression analysis. 3D Morphable Models (MMs) have become a popular tool to build and fit 3D face models to images. Critical to the success of MMs is the ability to build a generic 3D face model. Major limitations in the MMs building process are: (1) collecting 3D data usually involves the use of expensive laser scans and complex capture setups, (2) the number of available 3D databases is limited, and typically there is a lack of expression variability and (3) finding correspondences and registering the 3D model is a labor intensive and error prone process. 相似文献
106.
This paper presents an approach in designing a robust controller for vehicle suspensions considering changes in vehicle inertial properties. A four-degree-of-freedom half-car model with active suspension is studied in this paper, and three main performance requirements are considered. Among these requirements, the ride comfort performance is optimized by minimizing the H∞ norm of the transfer function from the road disturbance to the sprung mass acceleration, while the road holding performance and the suspension deflection limitation are guaranteed by constraining the generalized H2 (GH2) norms of the transfer functions from the road disturbance to the dynamic tyre load and the suspension deflection to be less than their hard limits, respectively. At the same time, the controller saturation problem is considered by constraining its peak response output to be less than a given limit using the GH2 norm as well. By solving the finite number of linear matrix inequalities (LMIs) with the minimization optimization procedure, the controller gains, which are dependent on the time-varying inertial parameters, can be obtained. Numerical simulations on both frequency and bump responses show that the designed parameter-dependent controller can achieve better active suspension performance compared with the passive suspension in spite of the variations of inertial parameters. 相似文献
107.
108.
在语音识别实际应用中,由于噪声的多样性,会造成训练和测试的失配,导致系统性能下降.特征补偿作为鲁棒性语音识别的一种重要方法,通过对训练和测试环境之间差异的研究,在特征空间中修正语音特征,使得修正后的测试语音特征能够更加接近训练语音特征.本文介绍一种实用的基于环境模型矢量泰勒级数(VTS)近似的特征补偿算法.首先验证传统的VTS离线算法在实际车载环境下的有效性;其次由于离线算法本身运算量很大,为了使其实用化,本文对算法进行改进,使其在提高效率的同时又能够保证与离线时相当的性能.通过实验结果验证,本文提出的实用化VTS算法在识别性能上相当接近离线时最好的性能. 相似文献
109.
提出一种新的图像去噪方法,它是Besov空间的变分模型,在负实数次Sobolev空间上定义了数据项,用Besov半范数定义了正则项。并详细推导了变分模型在Besov空间的阈值求解公式,先做一个Contourlet变换域的小阈值收缩,然后再利用该模型去噪。去除噪声的同时也损失了部分边缘信息,把边缘分为四种情况,针对不同情况确定相应的边缘补偿方法。实验表明该模型具有良好的去噪效果。 相似文献
110.
V. Malathi S. BaskarK. Ramar 《Engineering Applications of Artificial Intelligence》2011,24(5):880-887
This paper proposes a new approach based on combined Wavelet Transform-Extreme Learning Machine (WT-ELM) technique for fault section identification (whether the fault is before or after the series capacitor as observed from the relay point), classification and location in a series compensated transmission line. This method uses the samples of fault currents for half cycle duration from the inception of fault. The features of fault currents are extracted by first level decomposition of the current samples using discrete wavelet transform (DWT) and the extracted features are applied as inputs to ELMs for fault section identification, classification and location. The feasibility of the proposed method has been tested on a 400 kV, 300 km series compensated transmission line for all the ten types of faults using MATLAB simulink. On testing 28,800 fault cases with varying fault resistance, fault inception angle, fault distance, load angle, percentage compensation level and source impedance, the performance of the proposed method has been found to be quite promising. The results also indicate that the proposed method is robust to wide variation in system and operating conditions. 相似文献