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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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A High-performance Low Cost Inverse Integer Transform Architecture for AVS Video Standard
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作者 李宇飞 王琴 付宇卓 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期116-121,共6页
A high-performance, low cost inverse integer transform architecture for advanced video standard (AVS) video coding standard was presented. An 8 × 8 inverse integer transform is required in AVS video system whic... A high-performance, low cost inverse integer transform architecture for advanced video standard (AVS) video coding standard was presented. An 8 × 8 inverse integer transform is required in AVS video system which is compute-intensive. A hardware transform is inevitable to compute the transform for the real-time application. Compared with the 4 × 4 transform for H.264/AVC, the 8 × 8 integer transform is much more complex and the coefficient in the inverse transform matrix Ts is not inerratic as that in H.264/AVC. Dividing the Ts into matrix Ss and Rs, the proposed architecture is implemented with the adders and the specific CSA-trees instead of multipliers, which are area and time consuming. The architecture obtains the data processing rate up to 8 pixels per-cycle at a low cost of area. Synthesized to TSMC 0.18 μm COMS process, the architecture attains the operating frequency of 300 MHz at cost of 34 252 gates with a 2-stage pipeline scheme. A reusable scheme is also introduced for the area optimization, which results in the operating frequency of 143 MHz at cost of only 19 758 gates. 展开更多
关键词 inverse integer transform high-definitioin television (HDTV) carry-save adder (CSA) tree pipeline advanced video standard (AVS)
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Compression of ECG signal using video codec technology-like scheme
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作者 Dihu Chen Sheng Yang 《Journal of Biomedical Science and Engineering》 2008年第1期22-26,共5页
In this paper, we present a method using video codec technology to compress ECG signals. This method exploits both intra-beat and inter-beat correlations of the ECG signals to achieve high compression ratios (CR) and ... In this paper, we present a method using video codec technology to compress ECG signals. This method exploits both intra-beat and inter-beat correlations of the ECG signals to achieve high compression ratios (CR) and a low percent root mean square difference (PRD). Since ECG signals have both intra-beat and inter-beat redundancies like video signals, which have both intra-frame and inter-frame correlation, video codec technology can be used for ECG compression. In order to do this, some pre-process will be needed. The ECG signals should firstly be segmented and normalized to a sequence of beat cycles with the same length, and then these beat cycles can be treated as picture frames and compressed with video codec technology. We have used records from MIT-BIH arrhythmia database to evaluate our algorithm. Results show that, besides compression efficiently, this algorithm has the advantages of resolution adjustable, random access and flexibility for irregular period and QRS false detection. 展开更多
关键词 ECG compression video CODEC QRS detection ARITHMETIC coding
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Recent Advances in Video Coding for Machines Standard and Technologies
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作者 ZHANG Qiang MEI Junjun +3 位作者 GUAN Tao SUN Zhewen ZHANG Zixiang YU Li 《ZTE Communications》 2024年第1期62-76,共15页
To improve the performance of video compression for machine vision analysis tasks,a video coding for machines(VCM)standard working group was established to promote standardization procedures.In this paper,recent advan... To improve the performance of video compression for machine vision analysis tasks,a video coding for machines(VCM)standard working group was established to promote standardization procedures.In this paper,recent advances in video coding for machine standards are presented and comprehensive introductions to the use cases,requirements,evaluation frameworks and corresponding metrics of the VCM standard are given.Then the existing methods are presented,introducing the existing proposals by category and the research progress of the latest VCM conference.Finally,we give conclusions. 展开更多
关键词 video coding for machines VCM video compression
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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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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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Scalable Compression Algorithm for Video Monitoring System
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作者 王一拙 石峰 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期129-133,共5页
A layered compression algorithm is presented which delivers spatial scalable encoded bit streams for remote video monitoring system. The complexity of the algorithm is modest and is well suited to real time implementa... A layered compression algorithm is presented which delivers spatial scalable encoded bit streams for remote video monitoring system. The complexity of the algorithm is modest and is well suited to real time implementation. Based on the layered compression algorithm, a codec system model is established. High-speed video compression can be realized with parallel data compression in this codec system. For image reconstruction, a prediction method using two nearest pix points is presented. 展开更多
关键词 scalable compression layered compression video monitoring system multiple description coding
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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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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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Efficient Fast Multiplication Free Integer Transformation for the 1-D DCT of the H.265 Standard
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作者 Mohamed Nasr Haggag Mohamed El-Sharkawy +1 位作者 Gamal Fahmy Maher Rizkalla 《Journal of Software Engineering and Applications》 2010年第8期784-795,共12页
In this paper, efficient one-dimensional (1-D) fast integer transform algorithms of the DCT matrix for the H.265 stan-dard is proposed. Based on the symmetric property of the integer transform matrix and the matrix op... In this paper, efficient one-dimensional (1-D) fast integer transform algorithms of the DCT matrix for the H.265 stan-dard is proposed. Based on the symmetric property of the integer transform matrix and the matrix operations, which denote the row/column permutations and the matrix decompositions, along with using the dyadic symmetry modification on the standard matrix, the efficient fast 1-D integer transform algorithms are developed. Therefore, the computational complexities of the proposed fast integer transform are smaller than those of the direct method. In addition to computational complexity reduction one of the proposed algorithms provides transformation quality improvement, while the other provides more computational complexity reduction while maintaining almost the same transformation quality. With lower complexity and better transformation quality, the first proposed fast algorithm is suitable to accelerate the quality-demanding video coding computations. On the other hand, with the significant lower complexity, the second proposed fast algorithm is suitable to accelerate the video coding computations. 展开更多
关键词 FAST Algorithm HDTV H.265 ICT Order-16 transform video coding
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Design of the Quantization Matrix in the Distributed Compressed Sensing Video Coding*
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作者 Yueyue Dai Xinhua Rui Xuanyu Zhao 《Journal of Computer and Communications》 2016年第5期16-23,共8页
In the frame of compressed sensing distributed video coding, the design of the quantization matrix directly affects the reconstruction quality of the receiving terminal of the video. In this article, we present a new ... In the frame of compressed sensing distributed video coding, the design of the quantization matrix directly affects the reconstruction quality of the receiving terminal of the video. In this article, we present a new design method of the Gaussian quantization matrix adapting to the compressed sensing coding, for that the distribution of the parameters of the image is featured of the characteristic of approximately normal distribution after measured by compressive sensing. By this way, the parameters of a certain quantity of the image frames depending on the video sequences generated by the Gaussian quantization matrix possess certain adaptive capacity. By comparison with the plan of the traditional quantization, the quantization matrix presented in this article would improve the reconstruction quality of the video. 展开更多
关键词 compressed Sensing Distributed video coding Gaussian Quantization Matrix
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Residual Distributed Compressive Video Sensing Based on Double Side Information 被引量:2
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作者 CHEN Jian SU Kai-Xiong WANG Wei-Xing LAN Cheng-Dong 《自动化学报》 EI CSCD 北大核心 2014年第10期2316-2323,共8页
关键词 压缩视频 附加信息 分布式 感知 双面 残留 奈奎斯特速率 补偿技术
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Edge Oriented Compression Coding on Image Sequence 被引量:1
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作者 ZHANG Zhao yang GAO Lei ZHANG Ying CHEN Hao (School of Communication and Information Engineering, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第3期208-213,共6页
An edge oriented image sequence coding scheme is presented. On the basis of edge detecting, an image could be divided into the sensitized region and the smooth region. In this scheme, the architecture of sensitized r... An edge oriented image sequence coding scheme is presented. On the basis of edge detecting, an image could be divided into the sensitized region and the smooth region. In this scheme, the architecture of sensitized region is approximated with linear type of segments. Then a rectangle belt is constructed for each segment. Finally, the gray value distribution in the region is fitted by normal forms polynomials. The model matching and motion analysis are also based on the architecture of sensitized region. For the smooth region we use the run length scanning and linear approximating. By means of normal forms polynomial fitting and motion prediction by matching, the images are compressed. It is shown through the simulations that the subjective quality of reconstructed picture is excellent at 0.0075 bit per pel. 展开更多
关键词 video coding image compression very low bit rate edge oriented coding
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A WYNER-ZIV VIDEO CODING METHOD UTILIZING MIXTURE CORRELATION NOISE MODEL 被引量:1
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作者 Hu Xiaofei Zhu Xiuchang 《Journal of Electronics(China)》 2012年第3期197-203,共7页
In Wyner-Ziv (WZ) Distributed Video Coding (DVC), correlation noise model is often used to describe the error distribution between WZ frame and the side information. The accuracy of the model can influence the perform... In Wyner-Ziv (WZ) Distributed Video Coding (DVC), correlation noise model is often used to describe the error distribution between WZ frame and the side information. The accuracy of the model can influence the performance of the video coder directly. A mixture correlation noise model in Discrete Cosine Transform (DCT) domain for WZ video coding is established in this paper. Different correlation noise estimation method is used for direct current and alternating current coefficients. Parameter estimation method based on expectation maximization algorithm is used to estimate the Laplace distribution center of direct current frequency band and Mixture Laplace-Uniform Distribution Model (MLUDM) is established for alternating current coefficients. Experimental results suggest that the proposed mixture correlation noise model can describe the heavy tail and sudden change of the noise accurately at high rate and make significant improvement on the coding efficiency compared with the noise model presented by DIStributed COding for Video sERvices (DISCOVER). 展开更多
关键词 transform domain Wyner-Ziv (WZ) DIStributed coding for video sERvices (DISCOVER) video coding Correlation noise model Mixture Laplace-Uniform Distribution Model (MLUDM)
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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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Second Generation Wavelet Applied to Lossless Compression Coding of Image 被引量:1
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作者 Yan Tang Yu-long Mo 《Advances in Manufacturing》 2000年第3期225-229,共5页
In this paper, the second generation wavelet transform is applied to image lossless coding, according to its characteristic of reversible integer wavelet transform. The second generation wavelet transform can provide ... In this paper, the second generation wavelet transform is applied to image lossless coding, according to its characteristic of reversible integer wavelet transform. The second generation wavelet transform can provide higher compression ratio than Huffman coding while it reconstructs image without loss compared with the first generation wavelet transform. The experimental results show that the se cond generation wavelet transform can obtain excellent performance in medical image compression coding. 展开更多
关键词 wavelet transform integer wavelet image compression lossless coding
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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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An Introduction to High Efficiency Video Coding Range Extensions
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作者 Bin Li Jizheng Xu 《ZTE Communications》 2016年第1期12-18,共7页
High Efficiency Video Coding (HEVC) is the latest international video coding standard, which can provide the similar quality with about half bandwidth compared with its predecessor, H.264/MPEG?4 AVC. To meet the requi... High Efficiency Video Coding (HEVC) is the latest international video coding standard, which can provide the similar quality with about half bandwidth compared with its predecessor, H.264/MPEG?4 AVC. To meet the requirement of higher bit depth coding and more chroma sampling formats, range extensions of HEVC were developed. This paper introduces the coding tools in HEVC range extensions and provides experimental results to compare HEVC range extensions with previous video coding standards. Ex?perimental results show that HEVC range extensions improve coding efficiency much over H.264/MPEG?4 AVC High Predictive profile, especially for 4K sequences. 展开更多
关键词 H.265 High Efficiency video coding(HEVC) MPEG-H range extensions video compression
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High-Efficiency Video Coder in Pruned Environment Using Adaptive Quantization Parameter Selection
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作者 Krishan Kumar Mohamed Abouhawwash +2 位作者 Amit Kant Pandit Shubham Mahajan Mofreh A.Hogo 《Computers, Materials & Continua》 SCIE EI 2022年第10期1977-1993,共17页
The high-efficiency video coder(HEVC)is one of the most advanced techniques used in growing real-time multimedia applications today.However,they require large bandwidth for transmission through bandwidth,and bandwidth... The high-efficiency video coder(HEVC)is one of the most advanced techniques used in growing real-time multimedia applications today.However,they require large bandwidth for transmission through bandwidth,and bandwidth varies with different video sequences/formats.This paper proposes an adaptive information-based variable quantization matrix(AIVQM)developed for different video formats having variable energy levels.The quantization method is adapted based on video sequence using statistical analysis,improving bit budget,quality and complexity reduction.Further,to have precise control over bit rate and quality,a multi-constraint prune algorithm is proposed in the second stage of the AI-VQM technique for pre-calculating K numbers of paths.The same should be handy to selfadapt and choose one of the K-path automatically in dynamically changing bandwidth availability as per requirement after extensive testing of the proposed algorithm in the multi-constraint environment for multiple paths and evaluating the performance based on peak signal to noise ratio(PSNR),bit-budget and time complexity for different videos a noticeable improvement in rate-distortion(RD)performance is achieved.Using the proposed AIVQM technique,more feasible and efficient video sequences are achieved with less loss in PSNR than the variable quantization method(VQM)algorithm with approximately a rise of 10%–20%based on different video sequences/formats. 展开更多
关键词 Adaptive quantization high-efficient video coding(HEVC) quad-tree rate-distortion optimization(RDO) video compression variable quantization method(VQM) quantization parameter(QP)
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The Implementation of Mirror-Image Effect in MPEG-2 Compressed Video
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作者 倪强 周磊 张文军 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期151-156,共6页
Straightforward techniques for spatial domain digital video editing (DVE) of compressed video via decompression and recompression are computationally expensive. In this paper, a novel algorithm was proposed for mirror... Straightforward techniques for spatial domain digital video editing (DVE) of compressed video via decompression and recompression are computationally expensive. In this paper, a novel algorithm was proposed for mirror-image special effect editing in compressed video without full frame decompression and motion estimation. The results show that with the reducing of computational complexity, the quality of edited video in compressed domain is still close to the quality of the edited video in uncompressed domain at the same bit rate. 展开更多
关键词 digital video editing (DVE) compressed domain MPEG-2 mirror-image production discrete cosine transform (DCT) special effects
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