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Very Low Bit Rate Video Coding Using Motion Compensated 3 D Wavelet Transform
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作者 HOU Wei dong MO Yu long (School of Communication and Information Engineering, Shanghai University) HU Hai ping (School of Sciences, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第4期342-344,共3页
A new motion compensated 3 D wavelet transform (MC 3DWT) video coding scheme is presented in this paper. The new coding scheme has a good performance in average PSNR, compression ratio and visual quality of reconst... A new motion compensated 3 D wavelet transform (MC 3DWT) video coding scheme is presented in this paper. The new coding scheme has a good performance in average PSNR, compression ratio and visual quality of reconstructions compared with the existing 3 D wavelet transform (3DWT) coding methods and motion compensated 2 D wavelet transform (MC WT) coding method. The new MC 3DWT coding scheme is suitable for very low bit rate video coding. 展开更多
关键词 video coding very low bit rate 3 D wavelet transform motion compensation
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3-D Wavelet Transform for Very Low Bit-Rate Video Coding
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作者 Hou Weidong Mo Yulong Zhu Qiuyu Wei Chunlong (Shool of Communication and Information Engineering, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第2期48-51,共4页
A new improved Goh's 3 D wavelet transform(WT) coding scheme is presented in this paper. The new scheme has great advantages including a simple code structure, low computation cost and good performance in PSNR, c... A new improved Goh's 3 D wavelet transform(WT) coding scheme is presented in this paper. The new scheme has great advantages including a simple code structure, low computation cost and good performance in PSNR, compression ratios and visual quality of reconstructions, when compared to the other existing 3 D WT coding methods and the 2 D WT based coding methods. The new 3 D WT coding scheme is suitable for very low bit rate video coding. 展开更多
关键词 video coding video compression very low bit rate 3 D wavelet transform
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Global motion estimation with Gabor wavelet transform
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作者 王朋 刘重庆 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期645-650,共6页
A novel algorithm of global motion estimation is proposed. First, through Gabor wavelet transform (GWT), a kind of energy distribution of image is obtained and checkpoints are selected according to a probability dec... A novel algorithm of global motion estimation is proposed. First, through Gabor wavelet transform (GWT), a kind of energy distribution of image is obtained and checkpoints are selected according to a probability decision approach proposed. Then, the initialized motion vectors are obtained via a hierarcbal block-matching based on these checkpoints. Finally, by employing a 3-parameter motion model, precise parameters of global motion are found. From the experiment, the algorithm is reliable and robust. 展开更多
关键词 global motion estimation Gabor wavelet transform probability decision block-matching.
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Multiple description scalable video coding based on 3D lifted wavelet transform 被引量:3
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作者 KIM Yong-deak 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期857-863,共7页
In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multi... In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multiple description scalable coding (MDSC) is investigated, and novel MDSC schemes based on 3D wavelet coding are proposed, using the lifting imple- mentation of temporal filtering. The proposed MDSC schemes can avoid the mismatch problem in multiple description video coding, and have high scalability and robustness of video transmission. Experimental results showed that the proposed schemes are feasible and adequately effective. 展开更多
关键词 Multiple DESCRIPTION SCALABLE coding (MDSC) motion compensated temporal filtering (MCTF) Block-split bidi-rectional motion estimation 3D lifted wavelet transform
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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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AN EFFICIENT 3-DIMENSIONAL DISCRETE WAVELET TRANSFORM ARCHITECTURE FOR VIDEO PROCESSING APPLICATION 被引量:1
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作者 Ganapathi Hegde Pukhraj Vaya 《Journal of Electronics(China)》 2012年第6期534-540,共7页
This paper presents an optimized 3-D Discrete Wavelet Transform (3-DDWT) architecture. 1-DDWT employed for the design of 3-DDWT architecture uses reduced lifting scheme approach. Further the architecture is optimized ... This paper presents an optimized 3-D Discrete Wavelet Transform (3-DDWT) architecture. 1-DDWT employed for the design of 3-DDWT architecture uses reduced lifting scheme approach. Further the architecture is optimized by applying block enabling technique, scaling, and rounding of the filter coefficients. The proposed architecture uses biorthogonal (9/7) wavelet filter. The architecture is modeled using Verilog HDL, simulated using ModelSim, synthesized using Xilinx ISE and finally implemented on Virtex-5 FPGA. The proposed 3-DDWT architecture has slice register utilization of 5%, operating frequency of 396 MHz and a power consumption of 0.45 W. 展开更多
关键词 3-D Discrete wavelet transform (3-DDWT) Lifting scheme PIPELINING video coding Low power
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AN ALGORITHM FOR CODING VIDEO SIGNAL BASED ON 3-D WAVELET TRANSFORMATION
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作者 Wu Peng Zhang Miaolan Li Xianglin (Dept. of Electrical Eng., Graduate School, Uni. of Sci. and Tech. of China, Beijing 100039) 《Journal of Electronics(China)》 2000年第2期97-107,共11页
This paper presents an algorithm for coding video signal based on 3-D wavelet transformation. When the frame order t of a video signal is replaced by order 2, the video signal can be looked as a block in 3-D space. Af... This paper presents an algorithm for coding video signal based on 3-D wavelet transformation. When the frame order t of a video signal is replaced by order 2, the video signal can be looked as a block in 3-D space. After splitting the block into smaller sub-blocks, imitate the method of 2-D wavelet transformation for images, we can transform the sub-blocks with 3-D wavelet. Most of video signal energy is in the decomposed low-frequency sub-bands. These sub-bands affect the visual quality of the video signal most. Quantizing different sub-bands with different precision and then entropy encoding each sub-band, we can eliminate inter- and intra-frame redundancy of the video signal and compress data. Our simulation experiments show that this algorithm can achieve very good result. 展开更多
关键词 waveletS 3-D wavelet transformATION video signal coding
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MULTI-RESOLUTION MOTION ESTIMATION AND COMPENSATION BASED ON ADJACENT PREDICTION OF FRAME DIFFERENCE IN WAVELET DOMAIN 被引量:3
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作者 Tang Guowei Gu Guochang 《Journal of Electronics(China)》 2009年第3期412-416,共5页
Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame... Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted, the complexity of motion estimation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Resolution Motion Estimation(MRME) is improved. 展开更多
关键词 wavelet transforms motion estimation motion compensation Multi-resolution analysis video coding
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A Modified Block Matching Motion Estimation Algorithm for the Very Low Bit-Rate video Coding 被引量:1
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作者 Lu Guanming Bi Houjie and Jiang Ping (Department of Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing, 210003, P.R. China ) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1998年第2期24-29,共6页
Block matching motion estimation techniques have been widely used in video coding applications. However, they also show their deficiency in the coherence of motion vectors and antinoise ability. This paper proposes a... Block matching motion estimation techniques have been widely used in video coding applications. However, they also show their deficiency in the coherence of motion vectors and antinoise ability. This paper proposes a modified algorithm which can adopt any one of existing search algorithms and pays more attention to the correlation of neighboring blocks.It will be shown that the proposed algorithm is simple and significantly reduces the computational complexity. Simulation results also show that this algorithm improves the smoothness of the motion field, hence reducing the cost to code the motion vectors while keeping good performance comparable with the conventional block matching motion estimation algorithm. 展开更多
关键词 motion estimation video coding very low bit-rate coherence of motion vectors
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Multiresolution Video Watermarking Algorithm Exploiting the Block-Based Motion Estimation 被引量:2
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作者 Salwa A. K. Mostafa Abdelrahman Ali 《Journal of Information Security》 2016年第4期260-268,共9页
This paper presents a novel technique for embedding a digital watermark into video frames based on motion vectors and discrete wavelet transform (DWT). In the proposed scheme, the binary image watermark is divided int... This paper presents a novel technique for embedding a digital watermark into video frames based on motion vectors and discrete wavelet transform (DWT). In the proposed scheme, the binary image watermark is divided into blocks and each watermark block is embedded several times in each selected video frame at different locations. The block-based motion estimation algorithm is used to select the video frame blocks having the greatest motion vectors magnitude. The DWT is applied to the selected frame blocks, and then, the watermark block is hidden into these blocks by modifying the coefficients of the Horizontal sub-bands (HL). Adding the watermark at different locations in the same video frame makes the scheme more robust against different types of attacks. The method was tested on different types of videos. The average peak signal to noise ratio (PSNR) and the normalized correlation (NC) are used to measure the performance of the proposed method. Experimental results show that the proposed algorithm does not affect the visual quality of video frames and the scheme is robust against a variety of attacks. 展开更多
关键词 Digital video Watermarking wavelet transform motion Vector motion estimation video Frame
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VBR WAVELET VIDEO CODING AND ITS RATE CONTROL IN ATM NETWORKS
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作者 Lin Gang Tian Tiehong Liu Zemin(P.O.Box 96, School of Telecom. Engineering, Beijing Univ. of Posts and Telecom, Beijing 100876) 《Journal of Electronics(China)》 2000年第3期219-224,共6页
This paper presents a new video coding system based on wavelet transform and its rate control scheme over ATM networks. First, three dimensional wavelet transform is performed for the original image sequence, and an e... This paper presents a new video coding system based on wavelet transform and its rate control scheme over ATM networks. First, three dimensional wavelet transform is performed for the original image sequence, and an extension of set partitioning in hierarchical trees algorithm is employed to quantize the wavelet coefficients. Then, the output rate of the coder is controlled at group of frame scale, ensuring that it conforms to the parameters of a leaky bucket controller. Several leaky buckets with different sizes are discussed too. Simulation shows the efficiency of this codec and the effectiveness of the proposed rate control scheme. 展开更多
关键词 ATM networks video coding wavelet transform Rate control
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A CODING SCHEME USING GLOBAL MOTION ESTIMATION FOR AVS P-FRAME
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作者 Gong Shengrong Guo Li Cui Zhiming 《Journal of Electronics(China)》 2007年第6期815-820,共6页
Block matching has been used for motion estimation and motion compensation in the Au- dio and Video Standard (AVS) for years. While having an acceptable performance in describing mo- tion between frames, it requires q... Block matching has been used for motion estimation and motion compensation in the Au- dio and Video Standard (AVS) for years. While having an acceptable performance in describing mo- tion between frames, it requires quite a few bits to represent the motion vectors. In certain circum- stances, the use of global motion estimation and compensation would perform equally well or even better than the block matching in terms of motion accuracy, while it results in the coding of global motion model parameters. In this letter, we modify an AVS coder by adding (1) six global motion model parameters to the frame header, and (2) mode selection among INTRA, SKIP, INTER-16×16, INTER-16×8, INTER-8×16, INTER-8×8, and Global Motion Compensation (GMC) modes by La- grange optimal rate-distortion criteria. Simulation results demonstrate that over 0.1dB improvement in PSNR is obtained compared to the AVS coder for an average coded P-frame with the same bit- rate. 展开更多
关键词 coding scheme motion compensation motion estimation Audio and video Standard (AVS)
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Fast Implementation of VC-1 with Modified Motion Estimation and Adaptive Block Transform
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作者 Michael Tammen Mohamed El-Sharkawy +1 位作者 Hisham Sliman Maher Rizkalla 《Circuits and Systems》 2010年第1期12-17,共6页
The Society of Motion Picture and Television Engineers (SMPTE) Standard 421M, commonly known as VC-1, is a state-of-the-art video compression format that provides highly competitive video quality, from very low throug... The Society of Motion Picture and Television Engineers (SMPTE) Standard 421M, commonly known as VC-1, is a state-of-the-art video compression format that provides highly competitive video quality, from very low through very high bit rates, at a reasonable computational complexity. First, this paper presents fast motion compensation methods. The four motion estimation methods examined are fast, three step search, varying diamond, and 2D logarithmic. These methods use less search points than the full spiral scan used in the VC-1 reference software, which allows for faster motion estimation. Second, this paper presents a residual texture based choice of the block size for the Discrete Cosine Transform (DCT). To determine the block size, data is examined after the residual texture has been calculated. This is in contrast to the VC-1 reference software, which uses calculations at the block level to determine the block size. The residual texture of each block is small and uniform, allowing for simplified block choices. 展开更多
关键词 VC-1 motion estimation DISCRETE COSINE transform video Compression
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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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Fast Approaches for Sub-pixel Precision Variable Block Size Motion Estimation
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作者 张颖 萧允治 沈庭芝 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期209-214,共6页
The new features of H. 264 video coding standard make the motion estimation module much more time consuming than before. Especially, the motion search is required for each of the 4 modes for inter prediction. In order... The new features of H. 264 video coding standard make the motion estimation module much more time consuming than before. Especially, the motion search is required for each of the 4 modes for inter prediction. In order to reduce the computational complexity, we analyze the statistics of results of motion estimation, such as the continuity of best modes of blocks in successive frames and the chance to give up a sub-partition mode (smaller than 16 × 16) after integer-pixel motion estimation, from which we suggest to make mode prediction based on the motion information of the previous frame and skip sub-pixel motion estimation in subpartition mode selectively. According to the experimental result, the proposed algorithm can save 75 % of the computational time with a slight degradation (0.03 dB) on PSNR compared with the pseudocode of fast search motion estimation in JM12.2. 展开更多
关键词 video coding motion estimation SUB-PIXEL variable block size
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Very Low Bit-Rate Video Coding Based on Wavelet Transform
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作者 Hou Weidong Mo Yulong Wei Chunlong (School of Communication & Information Engineering) 《Advances in Manufacturing》 SCIE CAS 1998年第4期12-16,共5页
Two video coding schemes based on wavelet transform achieving very low bit rate are presented in this paper. The first is a hybrid motion compensated wavelet transform(MC WT)system which behaves better at very low ... Two video coding schemes based on wavelet transform achieving very low bit rate are presented in this paper. The first is a hybrid motion compensated wavelet transform(MC WT)system which behaves better at very low bit rates than the block DCT residual coder. The second is a new efficient coding system based on a simple frame differencing wavelet transform(FD WT)which performs well in both PSNR and visual quality with substantially reduced complexity. 展开更多
关键词 very low bit rate video coding wavelet transform video compression
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Hierarchical Search Motion Estimation Algorithms for Real-time Video Coding 被引量:2
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作者 Zhang Yong Yu Lu Zhou Feng Yao Qingdong (Zhejiang University, Hangzhou 310027) 《通信学报》 EI CSCD 北大核心 1998年第5期63-68,共6页
HierarchicalSearchMotionEstimationAlgorithmsforRealtimeVideoCodingZhangYongYuLuZhouFengYaoQingdong(ZhejiangU... HierarchicalSearchMotionEstimationAlgorithmsforRealtimeVideoCodingZhangYongYuLuZhouFengYaoQingdong(ZhejiangUniversity,Hangzh... 展开更多
关键词 图像编码 运动估计 分层搜索 视频通信
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A pixel-based outlier-free motion estimation algorithm for scalable video quality enhancement 被引量:2
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作者 Xuan DONG Jiangtao WEN 《Frontiers of Computer Science》 SCIE EI CSCD 2015年第5期729-740,共12页
Scalable video quality enhancement refers to the process of enhancing low quality frames using high quality ones in scalable video bitstreams with time-varying qualities. A key problem in the enhancement is how to sea... Scalable video quality enhancement refers to the process of enhancing low quality frames using high quality ones in scalable video bitstreams with time-varying qualities. A key problem in the enhancement is how to search for correspondence between high quality and low quality frames. Previous algorithms usually use block-based motion estimation to search for correspondences. Such an approach can hardly estimate scale and rotation transforms and always in- troduces outliers to the motion estimation results. In this paper, we propose a pixel-based outlier-free motion estimation algorithm to solve this problem. In our algorithm, the motion vector for each pixel is calculated with respect to estimate translation, scale, and rotation transforms. The motion relationships between neighboring pixels are considered via the Markov random field model to improve the motion estimation accuracy. Outliers are detected and avoided by taking both blocking effects and matching percentage in scale- invariant feature transform field into consideration. Experiments are conducted in two scenarios that exhibit spatial scalability and quality scalability, respectively. Experimental results demonstrate that, in comparison with previous algorithms, the proposed algorithm achieves better correspondence and avoids the simultaneous introduction of outliers, especially for videos with scale and rotation transforms. 展开更多
关键词 motion estimation scalable video coding videosuper resolution.
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Flexible three-band motion-compensated temporal filtering for scalable video coding
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作者 WANG Yong-yu SUN Qu YUAN Chao-wei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2009年第1期116-120,共5页
A novel scheme for scalable video coding using three-band lifting-based motion-compensated transform is presented in this article. A series of flexible three-band motion-compensated lifting steps are used to implement... A novel scheme for scalable video coding using three-band lifting-based motion-compensated transform is presented in this article. A series of flexible three-band motion-compensated lifting steps are used to implement the temporal wavelet transform, which provide improved compression performance by selecting specific motion model according to real video sequences, and offer higher temporal scalability flexibility by using three-band lifting steps. The experimental results compared with motion picture expert group (MPEG)-4 codec concerning standard video sequences demonstrate the effectiveness of the method. 展开更多
关键词 wavelet transform LIFTING scalable video coding three-band temporal decomposition motion-compensated temporal filtering (MCTF)
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A Video Coding Algorithm Based on Intraframe and Interframe Joint Prediction of Wavelet Coefficients
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作者 Zhang Xudong Wang Desheng Peng Yingning (Tsinghua University, Beijing 100084) 《通信学报》 EI CSCD 北大核心 1998年第5期11-17,共7页
AVideoCodingAlgorithmBasedonIntraframeandInterframeJointPredictionofWaveletCoeficientsZhangXudongWangDesheng... AVideoCodingAlgorithmBasedonIntraframeandInterframeJointPredictionofWaveletCoeficientsZhangXudongWangDeshengPengYingning(Tsin... 展开更多
关键词 视频编码 小波变换 运动估计 压缩
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