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基于CIF-to-QCIF变换的压缩域视频水印算法
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作者 曹华 周敬利 +1 位作者 余胜生 胡玉平 《计算机工程与应用》 CSCD 北大核心 2006年第14期65-68,94,共5页
现有视频水印算法的设计目标主要是对有损压缩、重量化编码等处理具有鲁棒性,但很少考虑视频帧格式变换因素,使水印对这类处理不具有鲁棒性。论文结合视频帧格式由CIF到QCIF的变换设计了一个压缩域的视频盲水印算法,水印被嵌入到CIF格... 现有视频水印算法的设计目标主要是对有损压缩、重量化编码等处理具有鲁棒性,但很少考虑视频帧格式变换因素,使水印对这类处理不具有鲁棒性。论文结合视频帧格式由CIF到QCIF的变换设计了一个压缩域的视频盲水印算法,水印被嵌入到CIF格式的视频流中,既可以从CIF视频中提取也可以从QCIF视频中提取,实验结果表明提出的算法对MPEG重编码以及CIF到QCIF的视频格式变换具有鲁棒性,而且整个嵌入提取过程都基于DCT域,具有较低的计算复杂度。 展开更多
关键词 视频水印 视频变换编码 CIF—to—QCIF变换
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A VIDEO SPECTRUM SPLITTING ENCODING SCHEME BASED ON HUMAN VISION AND ITS COMPUTER SIMULATION
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作者 赵宇 李华 +1 位作者 俞斯乐 滕建辅 《Transactions of Tianjin University》 EI CAS 1995年第1期79+76-79,共5页
In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Bas... In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Basically, this involves transmission of low frequency luminance information at full frame rate for good motion rendition and transmission of high frequency luminance signal at reduced frame rate for good detail in static images. 展开更多
关键词 D video encoding discrete wavelet transform human vision computer simulation
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AN IMPROVED ALL ZERO BLOCK FINDING METHOD BASED ON THE STATISTIC CHARACTERISTICS OF DCT TRANSFORM COEFFICIENTS
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作者 Xi Yinglai Hao Chongyang 《Journal of Electronics(China)》 2006年第1期99-102,共4页
In the H.263 video codec related systems, motion estimation and Discrete Cosine Transform (DCT) have the most computational requirements. In order to reduce complexity of the encoder to dedicate more resources to othe... In the H.263 video codec related systems, motion estimation and Discrete Cosine Transform (DCT) have the most computational requirements. In order to reduce complexity of the encoder to dedicate more resources to other functions, according to the study of existing methods, an Improved All Zero Block Finding (IAZBF) method based on the statistic characteristics of DCT coefficients is proposed. Compared with existing methods, IAZBF improves the detecting efficiency by about 50% without importing too much extra computation requirement. Being computed with additions and shifts instead of complicated multiplications, IAZBF is of low computation complexity, especially for low-end processors. In addition, IAZBF upholds picture fidelity and remains compatible with the H.263 bitstream standard. 展开更多
关键词 Discrete Cosine Transform (DCT) All-zero blocks Computation reduction
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A reversibility-gain model for integer Karhunen-Loève transform design in video coding
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作者 Xing-guo ZHU Lu YU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2015年第10期883-891,共9页
Karhunen-Loeve transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical probl... Karhunen-Loeve transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical problem. In this paper, a joint reversibility-gain (R-G) model is proposed for integer-KLT design in video coding. Specifically, the 'reversibility' is modeled according to distortion analysis in using forward and inverse integer transform without quantization. It not only measures how invcrtible a transform is, but also bounds the distortion introduced by the non-orthonormal integer transform process. The 'gain' means transform coding gain (TCG), which is a widely used criterion for transform design in video coding. Since KLT maximizes the TCG under some assumptions, here we define the TCG loss ratio (LR) to measure how much coding gain an integer-KLT loses when compared with the original KLT. Thus, the R-G model can be explained as follows: subject to a certain TCG LR, an integer- KLT with the best reversibility is the optimal integer transform for a given non-integer-KLT. Experimental results show that the R-G model can guide the design of integer-KLTs with good performance. 展开更多
关键词 Integer transform Karhunen-Loeve transform (KLT) Integer-KLT Transform coding Video coding
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