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RTP payload format for H.264/SVC scalable video coding 被引量:7
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作者 WENGER Stephan HANNUKSELA Miska M. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期657-667,共11页
The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design ... The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure. 展开更多
关键词 h.264 Advanced video coding (AVC) Scalable video coding (SVC) Scalability Real-time transport protocol (RTP) Packetization
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DCLSA:一种适用于H.264/AVC的DCT系数分层置乱算法 被引量:2
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作者 包先雨 蒋建国 李援 《中国图象图形学报》 CSCD 北大核心 2008年第4期618-623,共6页
基于目前的DCT系数加密算法在安全性、压缩比和信噪比上都各自存在缺点,提出了一种新的适用于H.264/AVC的DCT系数分层置乱算法(DCLSA)。该算法针对H.264/AVC中4×4DCT变换的特点,首先将同一宏块中每个4×4块DCT系数进行块间分层... 基于目前的DCT系数加密算法在安全性、压缩比和信噪比上都各自存在缺点,提出了一种新的适用于H.264/AVC的DCT系数分层置乱算法(DCLSA)。该算法针对H.264/AVC中4×4DCT变换的特点,首先将同一宏块中每个4×4块DCT系数进行块间分层,构建系数分层模型,然后可根据安全性要求对不同层系数进行随机置乱,实现加密编码。通过性能比较和具体实验效果分析,此算法具有更高的安全性、更优的压缩比和较好的信噪比,适合于H.264/AVC的网络安全应用。 展开更多
关键词 h.264/AVC dct系数置乱 视频加密 密钥同步
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H.264/AVC中的整数变换与DCT变换的比较 被引量:1
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作者 杜路泉 王泽勇 +1 位作者 王黎 高晓蓉 《现代电子技术》 2008年第20期131-133,138,共4页
数字视频技术在通信和广播领域获得了日益广泛的应用,视频信息和多媒体信息在网络中的处理和传输成为当前我国信息化中的热点技术。运动图像专家组和视频编码专家组给出一种更好的标准,确定为MPEG-4标准的第十部分,即H.264/AVC。简述H.... 数字视频技术在通信和广播领域获得了日益广泛的应用,视频信息和多媒体信息在网络中的处理和传输成为当前我国信息化中的热点技术。运动图像专家组和视频编码专家组给出一种更好的标准,确定为MPEG-4标准的第十部分,即H.264/AVC。简述H.264的研究意义及DCT的原理。为了减少运算量,分析H.264中如何对宏块的整数变换,详述H.264的编码变换的方法,给出整数变换方法与传统的DCT的区别和联系,并给出H.264的整数变换方法的快速算法即蝶形算法,这与传统的DCT变换是不同的。 展开更多
关键词 dct h.264 编码 蝶形算法 视频信息
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基于H.264的DCT变换系数解码的FPGA实现 被引量:2
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作者 梁盼 付永庆 陶宝泉 《应用科技》 CAS 2010年第2期20-23,共4页
根据H.264码流解码过程中整数DCT逆变换逆量化的算法原理,优化设计出一种基于FPGA的新型解决方案.设计采用VHDL和C语言相结合的编程方式,其中源数据的获取和分析在NIOSⅡ软核处理器中用C编程完成,各高效算法则用硬件描述语言VHDL编程实... 根据H.264码流解码过程中整数DCT逆变换逆量化的算法原理,优化设计出一种基于FPGA的新型解决方案.设计采用VHDL和C语言相结合的编程方式,其中源数据的获取和分析在NIOSⅡ软核处理器中用C编程完成,各高效算法则用硬件描述语言VHDL编程实现.说明了逆量化和逆变换的算法原理,各功能模块的设计流程和仿真结果.设计充分利用DCT算法的对称性,提出用高度并行结构来加快处理速度的方法.设计方案在保证运算精度的同时,结构简洁、运行速度快,可移植性强. 展开更多
关键词 h.264 dct 逆量化 FPGA
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H.264的整数DCT变换编码与量化过程 被引量:6
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作者 张晓燕 谢珺堂 《军民两用技术与产品》 2005年第5期40-42,45,共4页
H.264是由ITU与ISO两个国际组织共同联合开发的具有高编码效率、高压缩质量的视频新标准。H.264采用了4×4块的无乘法整数变换编码算法,不仅有效地降低了编解码的运算量,而且避免了反变换的误匹配问题。详细分析了H.264的整数DCT变... H.264是由ITU与ISO两个国际组织共同联合开发的具有高编码效率、高压缩质量的视频新标准。H.264采用了4×4块的无乘法整数变换编码算法,不仅有效地降低了编解码的运算量,而且避免了反变换的误匹配问题。详细分析了H.264的整数DCT变换的原理和实现,并阐述了与变换编码相应的量化过程。 展开更多
关键词 h.264 视频标准 编码效率 整数dct变换 匹配运算
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Very Low Bit-Rate Video Coding by Combining H.264/AVC Standard and 2-D Discrete Wavelet Transform
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作者 Ali Aghagolzadeh Saeed Meshgini +1 位作者 Mehdi Nooshyar Mehdi Aghagolzadeh 《Wireless Sensor Network》 2010年第4期328-336,共9页
In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is a... In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is applied on each video frame independently to extract the low frequency components for each frame and then the low frequency parts of all frames are coded using H.264/AVC codec. On the other hand, the high frequency parts of the video frames are coded by Run Length Coding algorithm, after applying a threshold to neglect the low value coefficients. Experiments show that our proposed method can achieve better rate-distortion performance at very low bit-rate applications below 16 kbits/s compared to applying H.264/AVC standard directly to all frames. Applications of our proposed video coding technique include video telephony, video-conferencing, transmitting or receiving video over half-rate traffic channels of GSM networks. 展开更多
关键词 video coding h.264/AVC STANDARD RUN Length coding Two-Dimensional WAVELET Transform
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H.264/AVC整数DCT变换与量化的FPGA实现 被引量:3
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作者 郁光珍 郑博 +1 位作者 李松亭 赵不贿 《电视技术》 北大核心 2011年第9期20-22,共3页
根据H.264/AVC的变换量化原理,在FPGA上设计并实现了整数变换及量化部分。首先采用层次化、模块化的思想,将系统划分为多个功能模块,降低了硬件实现的复杂度,对DCT算法进行了优化,并对量化模块采用了流水线操作,最后设计全部采用Verilo... 根据H.264/AVC的变换量化原理,在FPGA上设计并实现了整数变换及量化部分。首先采用层次化、模块化的思想,将系统划分为多个功能模块,降低了硬件实现的复杂度,对DCT算法进行了优化,并对量化模块采用了流水线操作,最后设计全部采用Verilog硬件描述语言实现,并用Modelsim进行功能仿真,同时实验结果通过在Xilinx公司Vertex2P系列的XC2VP30 FPGA上验证。仿真及综合结果表明,与优化之前相比,系统所需时钟周期减少了29个,最大时钟频率可达到135.498MHz,为H.264标准的硬件实现提供了参考。 展开更多
关键词 h.264 dct 量化 FPGA
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H.264/AVC中整数DCT变换量化模块的Verilog设计 被引量:1
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作者 沈劲桐 张卫 《计算机与现代化》 2013年第2期108-112,116,共6页
H.264/AVC视频压缩标准采用了4×4整数DCT变换和量化方法,避免了数据失配并提高了精度,具有较高的编码效率。本文分析H.264整数DCT变换和量化算法,将DCT变换转换为两次快速蝶形运算,减少了计算量,并用Verilog硬件描述语言编程实现整... H.264/AVC视频压缩标准采用了4×4整数DCT变换和量化方法,避免了数据失配并提高了精度,具有较高的编码效率。本文分析H.264整数DCT变换和量化算法,将DCT变换转换为两次快速蝶形运算,减少了计算量,并用Verilog硬件描述语言编程实现整数DCT变换和量化功能,利用QuartusII进行综合和仿真,得到正确的结果。本设计具有54.54MHz的时钟频率、较低的资源消耗和功耗。 展开更多
关键词 h 264 AVC 整数dct 量化 VERILOG hDL
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H.264中一种有效的对整数DCT系数的预测方法
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作者 雷亚锋 高鹏 吴枫 《计算机工程与应用》 CSCD 北大核心 2008年第23期71-74,共4页
提出了一种在H.264中减小DCT变换和量化计算量的新的有效方法。通过理论分析,研究了Normal4×4,LumaDC4×4和ChramaDC2×2这三种变换的系数动态分布,进而对变换和量化方法的三种类型提出相应的DCT系数量化为零三个充分条件... 提出了一种在H.264中减小DCT变换和量化计算量的新的有效方法。通过理论分析,研究了Normal4×4,LumaDC4×4和ChramaDC2×2这三种变换的系数动态分布,进而对变换和量化方法的三种类型提出相应的DCT系数量化为零三个充分条件。与文献中所提到的其它方法相比,该方法更加有效、精确。理论分析和实验结果表明:在减小计算复杂度、编码视频质量、错误接受率(false acceptance rate),错误拒绝率(false rejection rate)等方面,该方法都优于其它方法。 展开更多
关键词 视频编码 h.264 量化
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H.264/AVC零值量化DCT系数分级预判算法
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作者 曾鹏程 张小红 《江西理工大学学报》 CAS 2016年第1期87-94,共8页
在H.264/AVC标准算法中,运动补偿后的残差块经过4×4整数离散余弦变换(DCT)及量化过程后,往往出现大量的零值量化系数(ZQDCT),而这些零值系数完全可以通过提前判别来省略其变换量化过程.为了减少ZQDCT的冗余计算,在分析提取出最佳... 在H.264/AVC标准算法中,运动补偿后的残差块经过4×4整数离散余弦变换(DCT)及量化过程后,往往出现大量的零值量化系数(ZQDCT),而这些零值系数完全可以通过提前判别来省略其变换量化过程.为了减少ZQDCT的冗余计算,在分析提取出最佳全零块判决阈值的基础上,结合高斯分布模型和DCT系数能量"Z"形分布特性,提出了基于该新阈值的零值量化系数分级预判算法,在残差块DCT变换之前按分级模式预判出ZQDCT,从而跳过其变换量化操作.实验结果表明,与标准算法相比,该算法明显降低了编码数据量,同时减少了最高达42%的离散余弦变换(DCT)、量化(Q)、反量化(IQ)以及离散余弦反变换(IDCT)过程计算时间. 展开更多
关键词 h.264/AVC 零值量化系数 分级预判 高斯分布 Zigzag扫描
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Reversible Data Hiding Based on Run-Level Coding in H.264/AVC Video Streams
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作者 Yi Chen Hongxia Wang Xuyun Zhang 《Computers, Materials & Continua》 SCIE EI 2020年第5期911-922,共12页
This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for em... This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for embedding data into H.264/AVC video sequences.In order to guarantee the reversibility of the proposed scheme,the last nonzero quantized discrete cosine transform(DCT)coefficients in embeddable 4×4 blocks are shifted by the technology of histogram modification.The proposed scheme is realized after quantization and before entropy coding of H.264/AVC compression standard.Therefore,the embedded information can be correctly extracted at the decoding side.Peak-signal-noise-to-ratio(PSNR)and Structure similarity index(SSIM),embedding payload and bit-rate variation are exploited to measure the performance of the proposed scheme.Experimental results have shown that the proposed scheme leads to less SSIM variation and bit-rate increase. 展开更多
关键词 Reversible data hiding run-level coding visual quality bit-rate increase h.264/AVC video streams
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A rate control scheme for H.264 video under low bandwidth channel 被引量:11
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作者 YIN Ming WANG Hong-yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期990-995,共6页
The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are prop... The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are proposed to circumvent the dilemma, the inaccurate prediction model and improper bit allocation deter H.264 application on low bandwidth channel. To resolve this issue, this paper proposes a novel rate control scheme by considering the macroblock (MB) encoding complexity variation and buffer variation and by exploiting the spatio-temporal correlation sufficiently well. Simulations showed that this scheme improves the perceptual quality of the pictures with similar or smaller PSNR deviations when compared to that of rate control in JVT-O016. 展开更多
关键词 video coding h.264 Rate control hRD Bit allocation
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RATE CONTROL ALGORITHM FOR H.264 VIDEO ENCODER 被引量:2
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作者 Xue Jinzhu Shen Lansun (Signal & Information Processing Lab, Beijing University of Technology, Beijing 100022) 《Journal of Electronics(China)》 2003年第6期456-460,共5页
This letter proposes a rate control algorithm for H.264 video encoder, which is based on block activity and buffer state. Experimental results indicate that it has an excellent performance by providing much accurate b... This letter proposes a rate control algorithm for H.264 video encoder, which is based on block activity and buffer state. Experimental results indicate that it has an excellent performance by providing much accurate bit rate and better coding efficiency compared with H.264. The computational complexity of the algorithm is reduced by adopting a novel block activity description method using the Sum of Absolute Difference (SAD) of 16× 16 mode, and its robustness is enhanced by introducing a feedback circuit at frame layer. 展开更多
关键词 Rate control video coding h.264
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Analysis of Video Quality Variation with Different Bit Rates of H.264 Compression 被引量:1
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作者 Yen-Jen Chen Yang-Jen Lin Sheau-Ling Hsieh 《Journal of Computer and Communications》 2016年第5期32-40,共9页
The study applied a charge-coupled device (CCD) camera to send video signals to 4 DaVinci<sup>TM</sup> development boards (TMS320DM6446) of Texas Instruments (TI) to carry out H.264 Baseline Profile video ... The study applied a charge-coupled device (CCD) camera to send video signals to 4 DaVinci<sup>TM</sup> development boards (TMS320DM6446) of Texas Instruments (TI) to carry out H.264 Baseline Profile video coding. One of the development boards coded in the Variable Bit Rate (VBR) mode, and the other three development boards coded in the Constant Bit Rate (CBR) mode. In addition, the constant rates are 2 Mbps, 1.5 Mbps and 1 Mbps respectively. The H.264 video compression files produced by the boards were analyzed via video analysis software (CodecVisa) in the study. This software can analyze and present the compression data characteristics of the video files under each video frame, i.e., bits/MB, QP, and PSNR. In this research, the characteristics of data of each frame under four different compression conditions were compared. Their differences were calculated and averaged, and the standard deviation was evaluated. It was further connected with the values of quality characteristics and the peak signal to noise ratio (PSNR) of each frame to analyze the relation among the frame quality, the compression rate of CBR, as well as the quantitative granularity. The preliminary conclusion of the study is that the compression behaviors of CBRs in different coding sources are adjusted in a specific proportion in order to cope with the change in frame complexity. The frame will be severely damaged by a critical value during the process of network transmission while the source rate is less than the value of the characteristic. 展开更多
关键词 h.264 video coding CodecVisa PSNR VBR CBR QP
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Fast Inter Coding Mode Selection Algorithm for H.264
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作者 董海燕 张其善 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第3期219-224,共6页
In order to reduce the encoding complexity of macroblock coding mode decision in H.264/AVC, a selective smaller block-size searching algorithm and a selective intra coding mode searching algorithm are proposed by usin... In order to reduce the encoding complexity of macroblock coding mode decision in H.264/AVC, a selective smaller block-size searching algorithm and a selective intra coding mode searching algorithm are proposed by using the high correlation among coding modes and in spatial and temporal domains of video sequence. Simulation results demonstrate that the proposed algorithm can provide significant improvement in computational requirement, with negligible small picture quality degradation and slight bit rate increase. 展开更多
关键词 h.264 video coding motion estimation inter flame coding intra frame coding mode decision rate distortion
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Enhanced Adaptive Approach of Video Coding at Very Low Bit Rate Using MSPIHT Algorithm
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作者 C. Ravichandran N. Malmurugan 《Circuits and Systems》 2016年第8期1233-1241,共9页
Nowadays video coding approach is a major key in many applications for easy transmission and storage consumption. The process of transformation is based on the empirical wavelet transform (EWT). The encoding process o... Nowadays video coding approach is a major key in many applications for easy transmission and storage consumption. The process of transformation is based on the empirical wavelet transform (EWT). The encoding process of video data provides secure and less consumption of storage and the reconstruction process consists of the reverse process with the extraction. In this paper, the coding of video is carried out at a very low bit rate with the enhancement of performance by proposing an approach of modified Set Partitioning in Hierarchical Tree (MSPIHT). This method encodes the high frequency frames with the scheduling of wavelet transform for efficient performances of encoding and improves the ability of both the frequency and time. By applying empirical wavelet transform on each video frame, the component of video frequency is extracted and the low frequency frame is encoded by the H.264/AVC standard. The low coefficient values are ignored in applying the threshold and in the reconstruction process, HBLPCE method is used for imaging enhancement. The simulation of the proposed approach analysis shows better performance in reliable process and efficiency when compared to existing. 展开更多
关键词 video coding h.264 Standard Empirical Wavelet Transform PARTITION SPIhT hBLPCE
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基于FPGA的H.264解码核的实现
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作者 付永庆 姜灵灵 《应用科技》 CAS 2012年第3期9-14,共6页
对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化.介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高处理速度... 对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化.介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高处理速度,实现了解码结构上的优化.本算法在EP2S60F672C5ES FPGA上获得验证,结果表明给出的H.264解码算法是正确的,且有节省硬件资源和较快解码速度的优点. 展开更多
关键词 视频编码标准h.264/AVC h.264解码核 FPGA 句法预测 反量化 dct 帧内预测
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Performance Comparison of AVS and H.264/AVC Video Coding Standards 被引量:5
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作者 王新夫 赵德斌 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第3期310-314,共5页
A new audio and video compression standard of China,known as advanced Audio Video coding Standard (AVS).is emerging.This standard provides a technical solution for many applications within the information industry s... A new audio and video compression standard of China,known as advanced Audio Video coding Standard (AVS).is emerging.This standard provides a technical solution for many applications within the information industry such as digital broadcast,high-density laser—digital storage media,and so on.The basic part of AVS,AVS1-P2,targets standard definition (SD)and high definition(HD)format video compression,and aims to achieve similar coding efficiency as H.264/AVC but with lower computational complexity.In this paper,we first briefly describe the major coding tools in AVS1-P2,and then perform the coding efficiency comparison between AVS1-P2 Jizhun profile and H.264/AVC main profile.The experimental results show that the AVS1-P2 Jizhun profile has an average of 2.96% efficiency loss relative to H.264/AVC main profile in terms of bit-rate saving on HD progressive-scan sequences,and an average of 28.52% coding loss on interlace-scan sequences.Nevertheless,AVS1-P2 possesses a valuable feature of lower computational complexity. 展开更多
关键词 video coding image compression AVS h.264/AVC
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基于纹理特征的H.264视频隐写算法 被引量:1
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作者 张英男 张敏情 +1 位作者 刘佳 孙寿健 《科学技术与工程》 北大核心 2014年第28期93-97,共5页
针对当前视频隐蔽通信算法对视频质量以及码率有较大影响的问题,结合H.264/AVC编码标准,提出了一种新的视频隐蔽通信算法。算法根据离散余弦变换特点,对块依据纹理块判别准则进行判断,修改某些低频系数来进行嵌入。实验结果表明,该算法... 针对当前视频隐蔽通信算法对视频质量以及码率有较大影响的问题,结合H.264/AVC编码标准,提出了一种新的视频隐蔽通信算法。算法根据离散余弦变换特点,对块依据纹理块判别准则进行判断,修改某些低频系数来进行嵌入。实验结果表明,该算法对视频质量和码率有较小影响,并具有隐写容量大、抗隐写分析较好等优点。 展开更多
关键词 视频 信息隐藏 dct低频系数 h.264 纹理特征
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H.264视频编码器在DM6437上的优化实现 被引量:1
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作者 何苏勤 刘静 邢藏菊 《电子设计工程》 2012年第8期183-186,共4页
为了实现基于DSP的H.264视频编码器的实时性能,提出了一系列优化实现方法。首先结合TMS320DM6437硬件特点,描述了X264代码向TMS320DM6437平台的移植过程和优化方法,重点介绍了整数DCT变换和量化的线性汇编编写及汇编级优化。实验结果表... 为了实现基于DSP的H.264视频编码器的实时性能,提出了一系列优化实现方法。首先结合TMS320DM6437硬件特点,描述了X264代码向TMS320DM6437平台的移植过程和优化方法,重点介绍了整数DCT变换和量化的线性汇编编写及汇编级优化。实验结果表明,本编码器实现了cif格式视频的实时编码,Dl格式视频的编码速率也达到了18 fps,基本满足视频监控系统中编码器的需求。 展开更多
关键词 h.264 DM6437 整数dct 量化 移植 优化
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