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Improve Fractal Compression Encoding Speed Using Feature Extraction and Self-organization Network 被引量:1
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作者 Berthe Kya, Yang Yang Information Engineering School. University of Science and Technology Beijing. Beijing 100083. China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第4期306-310,共5页
Image compression consists of two main parts: encoding and decoding. One of the important problems of the fractal theory is the long encoding implementation time, which hindered the acceptance of fractal image compres... Image compression consists of two main parts: encoding and decoding. One of the important problems of the fractal theory is the long encoding implementation time, which hindered the acceptance of fractal image compression as a practical method. The long encoding time results from the need to perform a large number of domain-range matches, the total encoding time is the product of the number of matches and the time to perform each match. In order to improve encoding speed, a hybrid method combining features extraction and self-organization network has been provided, which is based on the feature extraction approach the comparison pixels by pixels between the feature of range blocks and domains blocks. The efficiency of the new method was been proved by examples. 展开更多
关键词 image compression fractal theory features extraction self-organization network fractal encoding
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A Simple Compression Method Using Motion Vector of the Distributed Video Encoder System
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作者 Yasuyuki Miura Sho Nakane Shigeyoshi Watanabe 《通讯和计算机(中英文版)》 2013年第1期49-58,共10页
关键词 压缩方法 视频编码器 运动矢量 编码系统 分布式 PC集群 数据传输 个人计算机
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基于Windows Media Encoder实现流媒体同步控制 被引量:4
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作者 毕野 施珺 《淮海工学院学报(自然科学版)》 CAS 2008年第4期24-27,共4页
基于Windows Media技术的流媒体同步控制需要ASF的支持。现有方法要求直接修改ASF文件的头对象而不易编程实现。通过对比研究,提出了一种基于Windows Media Encoder编码器后处理过程间接修改ASF文件的方法,并探讨了该方法的基本原理。... 基于Windows Media技术的流媒体同步控制需要ASF的支持。现有方法要求直接修改ASF文件的头对象而不易编程实现。通过对比研究,提出了一种基于Windows Media Encoder编码器后处理过程间接修改ASF文件的方法,并探讨了该方法的基本原理。实际系统中的成功应用证明了该方法能有效降低编程难度并易于集成,对实现流媒体同步控制具有一定的参考价值。 展开更多
关键词 流媒体 同步控制 ASF WINDOWS media Eneoder
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A REPEATED METHOD FOR ECG DATA COMPRESSION
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作者 李刚 刘蓉 +1 位作者 叶文宇 谌雅琴 《Transactions of Tianjin University》 EI CAS 2001年第3期157-161,共5页
A new electrocardiogram(ECG) data compression method is presented.It employs a repeated coding.In this method beat templates are extracted from original signals according to the features of ECG.The data are divided in... A new electrocardiogram(ECG) data compression method is presented.It employs a repeated coding.In this method beat templates are extracted from original signals according to the features of ECG.The data are divided into three parts:beat template,residual and position parameter.The three separate parts are first encoded with LADT,and then use the lossless entropy encoding to maintain a low level of reconstructed waveform distortion.The entropy encoding based on Huffman encoding is employed here as an example.Selections from the MIT BIH arrhythmia database,show that there is substantial improvement in compression ratio (CR) over other single and simple compression methods for comparable percent root mean square difference(PRD). 展开更多
关键词 repeated compression LADT Huffman encoding beat template RESIDUAL
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GLOBAL EXISTENCE AND BLOW-UP PHENOMENA OF CLASSICAL SOLUTIONS FOR THE SYSTEM OF COMPRESSIBLE ADIABATIC FLOW THROUGH POROUS MEDIA
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作者 刘法贵 孔德兴 《应用数学和力学》 EI CSCD 北大核心 2004年第6期643-652,共10页
By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result o... By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems. These results show that the dissipation is strong enough to preserve the smoothness of ‘small ’ solution. 展开更多
关键词 多孔介质 可压缩流体力学 方程组 经典解 整体存在性 破裂
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在Flash中基于Adobe Media Encoder组件的视频导入与应用方法
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作者 张佳丽 《电脑知识与技术》 2018年第7Z期215-216,共2页
在flash cs6的默认情况下,Flash cs6只支持flv和f4v格式的视频.如果不是这种格式的视频,我们可以使用Flash cs6自带的视频转换组件Adobe Media Encoder将其他视频格式转换成FLV和F4V格式.本文主要讲解如何使用flash自带的Adobe Media En... 在flash cs6的默认情况下,Flash cs6只支持flv和f4v格式的视频.如果不是这种格式的视频,我们可以使用Flash cs6自带的视频转换组件Adobe Media Encoder将其他视频格式转换成FLV和F4V格式.本文主要讲解如何使用flash自带的Adobe Media Encoder组件进行视频文件的转换,导入和使用. 展开更多
关键词 FLASH ADOBE media encoder组件 视频
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A New Elasticity and Finite Element Formulation for Different Young's Modulus When Tension and Compression Loadings 被引量:11
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作者 YEZhi-ming YuHuan-ran 《Journal of Shanghai University(English Edition)》 CAS 2001年第2期89-92,共4页
This paper presents a new elasticity and finite element formulation for different Young's modulus when tension and compression loadings in anisotropy media. The case studies, such as anisotropy and isotropy, were ... This paper presents a new elasticity and finite element formulation for different Young's modulus when tension and compression loadings in anisotropy media. The case studies, such as anisotropy and isotropy, were investigated. A numerical example was shown to find out the changes of neutral axis at the pure bending beams. 展开更多
关键词 elastic media anisotropy media different Young's modulus tension compression finite element formulation
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GLOBAL EXISTENCE AND BLOW-UP PHENOMENA OF CLASSICAL SOLUTIONS FOR THE SYSTEM OF COMPRESSIBLE ADIABATIC FLOW THROUGH POROUS MEDIA 被引量:2
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作者 刘法贵 孔德兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期703-713,共11页
By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result o... By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems. These results show that the dissipation is strong enough to preserve the smoothness of ‘small ’ solution. 展开更多
关键词 porous media compressible adiabatic flow system of equations classical solution global existence BLOW-UP
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Fast encoding algorithm for vector quantization based on subvector L_2-norm 被引量:1
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作者 Chen Shanxue Li Fangwei Zhu Weile 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期611-617,共7页
A fast encoding algorithm based on the mean square error (MSE) distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform (WT) coefficients of images, can... A fast encoding algorithm based on the mean square error (MSE) distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform (WT) coefficients of images, can simplify the realization of the non-linear interpolated vector quantization (NLIVQ) technique and make the partial distance search (PDS) algorithm more efficient. Utilizing the relationship of vector L2-norm and its Euclidean distance, some conditions of eliminating unnecessary codewords are obtained. Further, using inequality constructed by the subvector L2-norm, more unnecessary codewords are eliminated. During the search process for code, mostly unlikely codewords can be rejected by the proposed algorithm combined with the non-linear interpolated vector quantization technique and the partial distance search technique. The experimental results show that the reduction of computation is outstanding in the encoding time and complexity against the full search method. 展开更多
关键词 image compression fast encoding subvector wavelet transform vector quantization.
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TWO PHASE COMPRESSIBLE FLOW IN POROUS MEDIA 被引量:1
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作者 应隆安 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2159-2168,共10页
We study the mathematical model of two phase compressible flows through porous media. Under the condition that the compressibility of rock, oil, and water is small, we prove that the initial-boundary value problem of ... We study the mathematical model of two phase compressible flows through porous media. Under the condition that the compressibility of rock, oil, and water is small, we prove that the initial-boundary value problem of the nonlinear system of equations admits a weak solution. 展开更多
关键词 porous media two phase compressible flows initial-boundary value problem
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An efficient multigrid-DEIM semi-reduced-order model for simulation of single-phase compressible flow in porous media 被引量:1
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作者 Jing-Fa Li Bo Yu +2 位作者 Dao-Bing Wang Shu-Yu Sun Dong-Liang Sun 《Petroleum Science》 SCIE CAS CSCD 2021年第3期923-938,共16页
In this paper,an efcient multigrid-DEIM semi-reduced-order model is developed to accelerate the simulation of unsteady single-phase compressible fow in porous media.The cornerstone of the proposed model is that the fu... In this paper,an efcient multigrid-DEIM semi-reduced-order model is developed to accelerate the simulation of unsteady single-phase compressible fow in porous media.The cornerstone of the proposed model is that the full approximate storage multigrid method is used to accelerate the solution of fow equation in original full-order space,and the discrete empirical interpolation method(DEIM)is applied to speed up the solution of Peng-Robinson equation of state in reduced-order subspace.The multigrid-DEIM semi-reduced-order model combines the computation both in full-order space and in reducedorder subspace,which not only preserves good prediction accuracy of full-order model,but also gains dramatic computational acceleration by multigrid and DEIM.Numerical performances including accuracy and acceleration of the proposed model are carefully evaluated by comparing with that of the standard semi-implicit method.In addition,the selection of interpolation points for constructing the low-dimensional subspace for solving the Peng-Robinson equation of state is demonstrated and carried out in detail.Comparison results indicate that the multigrid-DEIM semi-reduced-order model can speed up the simulation substantially at the same time preserve good computational accuracy with negligible errors.The general acceleration is up to 50-60 times faster than that of standard semi-implicit method in two-dimensional simulations,but the average relative errors of numerical results between these two methods only have the order of magnitude 10^(−4)-10^(−6)%. 展开更多
关键词 compressible fow Porous media Multigrid method Discrete empirical interpolation method Peng-Robinson equation of state
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Text Compression Based on Letter’s Prefix in the Word
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作者 Majed AbuSafiya 《Computers, Materials & Continua》 SCIE EI 2020年第7期17-30,共14页
Huffman[Huffman(1952)]encoding is one of the most known compression algorithms.In its basic use,only one encoding is given for the same letter in text to compress.In this paper,a text compression algorithm that is bas... Huffman[Huffman(1952)]encoding is one of the most known compression algorithms.In its basic use,only one encoding is given for the same letter in text to compress.In this paper,a text compression algorithm that is based on Huffman encoding is proposed.Huffman encoding is used to give different encodings for the same letter depending on the prefix preceding it in the word.A deterministic finite automaton(DFA)that recognizes the words of the text is constructed.This DFA records the frequencies for letters that label the transitions.Every state will correspond to one of the prefixes of the words of the text.For every state,a different Huffman encoding is defined for the letters that label the transitions leaving that state.These Huffman encodings are then used to encode the letters of the words in the text.This algorithm was implemented and experimental study showed significant reduction in compression ratio over the basic Huffman encoding.However,more time is needed to construct these codes. 展开更多
关键词 Text compression Huffman encoding deterministic finite automata
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Data compression of displacement fields in digital image correlation by non-integer quantization
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作者 Chen Wenwu Shao Xinxing He Xiaoyuan 《Journal of Southeast University(English Edition)》 EI CAS 2022年第1期42-48,共7页
To solve the real-time transmission problem of displacement fields in digital image correlation,two compression coding algorithms based on a discrete cosine transform(DCT)and discrete wavelet transform(DWT)are propose... To solve the real-time transmission problem of displacement fields in digital image correlation,two compression coding algorithms based on a discrete cosine transform(DCT)and discrete wavelet transform(DWT)are proposed.Based on the Joint Photographic Experts Group(JPEG)and JPEG 2000 standards,new non-integer and integer quantizations are proposed in the quantization procedure of compression algorithms.Displacement fields from real experiments were used to evaluate the compression ratio and computational time of the algorithm.The results show that the compression ratios of the DCT-based algorithm are mostly below 10%,which are much less than that of the DWT-based algorithm,and the computational speed is also significantly higher than that of the latter.These findings prove the algorithm s effectiveness in real-time displacement field wireless transmission. 展开更多
关键词 digital image correlation wireless transmission displacement field compression encoding
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A New Method Which Combines Arithmetic Coding with RLE for Lossless Image Compression
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作者 Med Karim Abdmouleh Atef Masmoudi Med Salim Bouhlel 《Journal of Software Engineering and Applications》 2012年第1期41-44,共4页
This paper presents a new method of lossless image compression. An image is characterized by homogeneous parts. The bit planes, which are of high weight are characterized by sequences of 0 and 1 are successive encoded... This paper presents a new method of lossless image compression. An image is characterized by homogeneous parts. The bit planes, which are of high weight are characterized by sequences of 0 and 1 are successive encoded with RLE, whereas the other bit planes are encoded by the arithmetic coding (AC) (static or adaptive model). By combining an AC (adaptive or static) with the RLE, a high degree of adaptation and compression efficiency is achieved. The proposed method is compared to both static and adaptive model. Experimental results, based on a set of 12 gray-level images, demonstrate that the proposed scheme gives mean compression ratio that are higher those compared to the conventional arithmetic encoders. 展开更多
关键词 Adaptive ARITHMETIC CODING Static ARITHMETIC CODING ARITHMETIC CODING LOSSLESS compression Image RUN Length encoding
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A multi-modal clustering method for traditonal Chinese medicine clinical data via media convergence
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作者 Jingna Si Ziwei Tian +6 位作者 Dongmei Li Lei Zhang Lei Yao Wenjuan Jiang Jia Liu Runshun Zhang Xiaoping Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期390-400,共11页
Media convergence is a media change led by technological innovation.Applying media convergence technology to the study of clustering in Chinese medicine can significantly exploit the advantages of media fusion.Obtaini... Media convergence is a media change led by technological innovation.Applying media convergence technology to the study of clustering in Chinese medicine can significantly exploit the advantages of media fusion.Obtaining consistent and complementary information among multiple modalities through media convergence can provide technical support for clustering.This article presents an approach based on Media Convergence and Graph convolution Encoder Clustering(MCGEC)for traditonal Chinese medicine(TCM)clinical data.It feeds modal information and graph structure from media information into a multi-modal graph convolution encoder to obtain the media feature representation learnt from multiple modalities.MCGEC captures latent information from various modalities by fusion and optimises the feature representations and network architecture with learnt clustering labels.The experiment is conducted on real-world multimodal TCM clinical data,including information like images and text.MCGEC has improved clustering results compared to the generic single-modal clustering methods and the current more advanced multi-modal clustering methods.MCGEC applied to TCM clinical datasets can achieve better results.Integrating multimedia features into clustering algorithms offers significant benefits compared to single-modal clustering approaches that simply concatenate features from different modalities.It provides practical technical support for multi-modal clustering in the TCM field incorporating multimedia features. 展开更多
关键词 graph convolutional encoder media convergence multi-modal clustering traditional Chinese medicine
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让你的声音“流”遍全球——用Media Encoder打造你的实时网络电台
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作者 冷星峰 《电脑知识与技术(过刊)》 2003年第4期64-67,共4页
随着网络时代的爆发,网络几乎渗透到人们的整个生活:网上娱乐、网络购物、获得最快的网络新闻……这以往在电影里面才能看到的一切,今天已经走进了千千万万老百姓的家里。当然在网上听音乐、看电影已是再平常不过的事情,但在网上建一个... 随着网络时代的爆发,网络几乎渗透到人们的整个生活:网上娱乐、网络购物、获得最快的网络新闻……这以往在电影里面才能看到的一切,今天已经走进了千千万万老百姓的家里。当然在网上听音乐、看电影已是再平常不过的事情,但在网上建一个即时的网络小电台,尝尝电台主持人的滋味,则仍然是众多网友多年的梦想。其实搭建网络电台并不是一件困难的事情,只要花点时间、多点耐性,就可以让你的声音在网络中通过流媒体的形式“流”遍全球的各个角落。不过至于能不能一炮成名、电台有多少听众这就要看大家自己的努力了。 展开更多
关键词 media encodER 网络电台 计算机网络 应用程序 声卡
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玩玩电影 聊聊编码——WMV之瑞士军刀·Windows Media Encoder9
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《计算机应用文摘》 2005年第10期45-45,共1页
Windrows Media Encoder 9足微软发布的WMV9媒体编码戟件。它的功能非常强大,不但能对视频文件进行编码压缩,还能进行视频采集和网络广播。
关键词 media Windows 瑞士军刀 WMV encodER 电影 媒体编码 编码压缩 视频文件 网络广播 视频采集 发布 微软
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考虑气体的渗流应力耦合模型在黄壁庄水库中的应用
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作者 赵兰浩 王卫国 张海容 《水力发电》 CAS 2024年第5期76-81,共6页
目前建立的多孔介质耦合模型通常认为气体是不可压缩的,无法描述气体的输运过程,无法反映气体对水体入渗和固体变形的影响。为了描述多孔介质中固液气三相的渗流应力耦合过程,基于多孔介质理论和有效应力原理,提出了一种耦合了改进守恒... 目前建立的多孔介质耦合模型通常认为气体是不可压缩的,无法描述气体的输运过程,无法反映气体对水体入渗和固体变形的影响。为了描述多孔介质中固液气三相的渗流应力耦合过程,基于多孔介质理论和有效应力原理,提出了一种耦合了改进守恒水平集(ICLS)方法并考虑气体可压缩性的固液气三相渗流应力耦合模型。将该方法应用于黄壁庄水库坝前冒泡现象的渗流应力耦合分析中,模拟了水位骤升后,固体变形、水体入渗和气体运移过程,及其耦合效应。计算结果表明,该方法能够简单直观的描述水气两相的运移过程及渗流应力耦合过程,且模拟结果与实际观测结果基本一致。 展开更多
关键词 渗流应力耦合模型 气体可压缩 多孔介质 ICLS方法 有限元法 黄壁庄水库
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基于深度学习的高能同步辐射光源数据快速无损压缩算法
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作者 张敏行 符世园 +2 位作者 高宇 程耀东 陈刚 《计算机应用》 CSCD 北大核心 2024年第S01期95-100,共6页
高能同步辐射光源(HEPS)产生的高帧率、高分辨率图像数据以样本为单位存储,每个样本对应近千张灰度图。通用无损压缩方法对此类图像压缩效果不佳,而基于深度学习的压缩方法通常压缩解压耗时较长。为了解决上述问题,结合光源图像数据特点... 高能同步辐射光源(HEPS)产生的高帧率、高分辨率图像数据以样本为单位存储,每个样本对应近千张灰度图。通用无损压缩方法对此类图像压缩效果不佳,而基于深度学习的压缩方法通常压缩解压耗时较长。为了解决上述问题,结合光源图像数据特点,提出一种基于深度学习的快速无损压缩算法。以样本对应的图像序列为单位压缩,根据少量前向帧利用时空学习网络预测图像取值并编码残差图,以实现高压缩比(CR);此外,通过图像子集划分和子集次优编码方法,将图像序列划分为多个子集并构建编码表,从而减少压缩解压缩耗时。经过测试,相较于PNG、JPEG2000等传统图像无损压缩算法,所提算法的CR提升了0.22~0.68;相较于DeepZip等深度学习无损压缩算法,所提算法的压缩耗时减少了41.0%以上,解压缩耗时减少了9.3%以上。 展开更多
关键词 图像压缩 深度学习 图像分组 无损压缩 编码方法
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基于Windows Media SDK的DRM系统开发 被引量:3
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作者 董纳 杨静 +1 位作者 苑红晓 常立立 《计算机系统应用》 2006年第2期37-40,56,共5页
随着网络的发展,数字媒体文件的盗版问题的日益泛滥,Microsoft Windows Media 9在编码过程中提供了对数字权限管理(DRM)的支持,可实现对数字媒体文件的加密保护。该文简要介绍了Microsoft的DRM技术原理及工作流程,叙述了如何采用DRM技... 随着网络的发展,数字媒体文件的盗版问题的日益泛滥,Microsoft Windows Media 9在编码过程中提供了对数字权限管理(DRM)的支持,可实现对数字媒体文件的加密保护。该文简要介绍了Microsoft的DRM技术原理及工作流程,叙述了如何采用DRM技术保护网站上的音频和视频资料。重点描述了如何基于Windows Media Rights Manager SDK创建认证服务器,提供认证许可的发放及身份的验证,如何基于Windows Media Encoder SDK 创建一个数字权限管理(DRM)系统来生成密钥、打包、加密和发行数字媒体内容。 展开更多
关键词 数字媒体认证服务Windows media encoder SDK Windows media RIGHTS Manager数字权限管理(DRM)加 密解密
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