Description: 运动估计是视频压缩中帧间预测编码的关键技术之一，在各个压缩标准中都广泛使用了基于块的运动估计技术。由于运动估计通常具有较大的运算量，因此对压缩性能具有重要的影响。本文在分析了视频序列的特点和对现有的快速搜索算法深入理解的基础上提出了一种改进的快速运动估计搜索算法，通过实验表明该算法对压缩性能有了较好的改进。
-Video Compression interframe predictive coding one of the key technologies. in various compression standards has made extensive use of block-based motion estimation technology. As the motion estimation is usually larger amount of computation, so the compression performance has a significant influence. Based on the analysis of the video sequence and the characteristics of the existing Quick Search Algorithm in-depth understanding on the basis of a modified Quick search motion estimation algorithm, experiments show that the algorithm has better compression performance improvements. Platform: |
Size: 22302 |
Author:刘昌劲 |
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Description: Image Compression
A collection of simple routines for image compression using different techniques.
BTCODE:
Image compression Using Block Truncation Coding.
PYRAMID:
Image compression based on Gaussian Pyramids.
DCTCOMPR:
Image compression based on Discrete Cosine Transform.
IMCOMPR:
Image compression based on Singular Value Decomposition.
The given codes can be also used in 2D noise suppression.
Platform: |
Size: 10066 |
Author:林明 |
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Description: 本文结合DCT变换的特性，利用分形的Peano一hilbert扫描曲线，对基于DCT变换的图像编码方法进行了研究，并提出了改进方法。主要工作分为两个部分: 一是在分块DCT基础上的改进。对分块后生成的各图像块矩阵，不直接作二维DCT变换，而是先进行扫描，使之重排成一维向量，再进行一维DCT变换，这样可以减少运算量。 其次是对层次余弦变换编码部分的改进。使用层次DCT变换与零树编码相结合的方法，并在扫描编码过程中，按Peano一hilbert扫描顺序进行编码。这样不仅可以减少“块效应”，而且可以加快编码速度。-this paper the characteristics of DCT, using fractal Peano a Hilbert scanning curve, the DCT-based image coding method for the study and improvement of methods. The work is divided into two main parts : First, the DCT block on the basis of improvements. Right after block production of the image block matrix, not for direct two-dimensional DCT, but first scan, so they line up in a heavy-dimensional vector and then a peacekeeping DCT, thus reducing the amount of computation. Secondly, the level of cosine transform coding some of the improvements. The use level of DCT and zero tree coding combination of methods, coding and scanning process, according to a Hilbert Peano code scanning sequence. This will not only reduce the "blocking effect" but we can speed up the coding speed. Platform: |
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Author:lzy |
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Description: 运动估计是视频压缩中帧间预测编码的关键技术之一，在各个压缩标准中都广泛使用了基于块的运动估计技术。由于运动估计通常具有较大的运算量，因此对压缩性能具有重要的影响。本文在分析了视频序列的特点和对现有的快速搜索算法深入理解的基础上提出了一种改进的快速运动估计搜索算法，通过实验表明该算法对压缩性能有了较好的改进。
-Video Compression interframe predictive coding one of the key technologies. in various compression standards has made extensive use of block-based motion estimation technology. As the motion estimation is usually larger amount of computation, so the compression performance has a significant influence. Based on the analysis of the video sequence and the characteristics of the existing Quick Search Algorithm in-depth understanding on the basis of a modified Quick search motion estimation algorithm, experiments show that the algorithm has better compression performance improvements. Platform: |
Size: 22528 |
Author:刘昌劲 |
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Description: Image Compression
A collection of simple routines for image compression using different techniques.
BTCODE:
Image compression Using Block Truncation Coding.
PYRAMID:
Image compression based on Gaussian Pyramids.
DCTCOMPR:
Image compression based on Discrete Cosine Transform.
-Image Compression A collection of simple r outines for image compression using different techniques. BTCODE : Image compression Using Block Truncation Codi Vi. PYRAMID : Image compression based on Gaussian Pyramids. DCTCOMPR : Image compression based on Discrete Cosine trapidil nsform. Platform: |
Size: 9216 |
Author:like |
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Description: 提出一种基于视觉特性的图像摘要算法，增大人眼敏感的频域系数在计算图像Hash时的权重，使得图像Hash更好地体现视觉特征，并提高鲁棒性。将原始图像的分块DCT系数乘以若干由密钥控制生成的伪随机矩阵，再对计算的结果进行基于分块的Watson人眼视觉特性处理，最后进行量化判决产生固定长度的图像Hash序列。本算法比未采用视觉特性的算法相比，提高了对JPEG压缩和高斯滤波的鲁棒性。图像摘要序列由密钥控制生成，具有安全性。-Based on the visual characteristics of the image digest algorithm, increasing the human eye-sensitive frequency-domain coefficients in the calculation of the image when the weight of Hash, Hash makes images better reflect the visual characteristics, and improve robustness. Will block the original image multiplied by the number of DCT coefficients generated by the key control of pseudo-random matrix, then the results of calculation based on the sub-block of Watson HVS treatment, and finally quantify the judgments arising from fixed-length sequence of images Hash . Than the algorithm did not use the visual characteristics of the algorithm, improve the JPEG compression and Gaussian filtering robustness. Abstract image sequence generated by the key control, with security. Platform: |
Size: 167936 |
Author:kurt |
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Description: Image Compression
A collection of simple routines for image compression using different techniques.
BTCODE:
Image compression Using Block Truncation Coding.
PYRAMID:
Image compression based on Gaussian Pyramids.
DCTCOMPR:
Image compression based on Discrete Cosine Transform.
IMCOMPR:
Image compression based on Singular Value Decomposition.
The given codes can be also used in 2D noise suppression.
Platform: |
Size: 10240 |
Author:林明 |
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Description: 基于小波变换的图像压缩变换
编码最常用的有子带编码和块编码，本实验做了基于小波变换的子带压缩部分。-Based on wavelet transform image compression transform coding has the most commonly used sub-band coding and block coding, to do this experiment based on the wavelet transform part of the sub-band compression. Platform: |
Size: 51200 |
Author:吴亚鹏 |
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Description: 用matlab做的基于DCT变换的图像压缩源码，先把图像分成8X8 的子块，然后做DCT变换，再量化，在恢复重建图像-Using matlab to do DCT-based transform image compression source code, first image is divided into 8x8 sub-block, and then make DCT transform, and then quantified, at the resumption of the reconstructed image Platform: |
Size: 1024 |
Author:张子木 |
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Description: 一系列展示图像压缩技术的源代码。包括有：使用块截断编码的图像压缩(Block Truncation)、基于高斯金字塔变换的图像压缩(Gaussian Pyramids)、基于离散余弦变换对图像压缩(Discrete Cosine Transform)、基于奇异值分解(SVD)的图像压缩(Singular Value Decomposition)。给出的代码还可以用于2D图像噪声消除-A series of image compression technology to display the source code. Include: the use of block truncation coding for image compression (Block Truncation), based on the Gaussian pyramid transform for image compression (Gaussian Pyramids), based on the discrete cosine transform for image compression (Discrete Cosine Transform), based on singular value decomposition (SVD) Image compression (Singular Value Decomposition). Given code can also be used in 2D image noise cancellation Platform: |
Size: 44032 |
Author:李远 |
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Description: 基于块方向的图像无损压缩代码，压缩包解压时不能有密码，不含res和DEBUG-Block-based direction of image lossless compression code, when extracting compressed package should not have a password, non-res and DEBUG Platform: |
Size: 4760576 |
Author:Ry |
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Description: 分块有损压缩图像忽略了块间相关性，重构时会产生块效应，该文提出一种空域自适应去块效应算法。对块边缘采用方向自适应
有理滤波，以弱化块效应。根据块的内部活动性将图像块分成平坦块和纹理块2 类，利用基于方差的空域检测方法检测出平坦块，并对平
坦块进行邻块边缘自适应平滑。实验结果表明，该算法有效去除了块效应，一定程度上提高了信噪比，算法简单且鲁棒性较好。-Block lossy compression image ignores the inter-block correlation, Reconstruction would have a blocking effect, the paper presents a airspace Adaptive Deblocking Algorithm. To block the edge of rational use of the direction of adaptive filtering, in order to weaken the block effect. According to block the internal activity of the image block is divided into a flat block and texture block 2 categories, the use of airspace based on the variance detection methods to detect the flat block, and a flat block adjacent block edge adaptive smoothing. Experimental results show that the algorithm effectively blocking go except, to some extent, improve the signal to noise ratio, the algorithm is simple and better robustness. Platform: |
Size: 147456 |
Author:子登 |
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Description: 已知两个不同图像块亮度数据如下：
（1）分析DCT原理，采用DCT方法，编程并计算相应的DCT系数，分析系数分布特点。
（2）依据视觉特性分析量化表步长的分布特点，完成DCT系数量化。
（3）采用Z形扫描，实现输出数据的统计编码，形成Video stream。
（4）采用IDCT重建图像亮度数据，计算SAD大小，分析产生误差的原因及采用DCT进行数据压缩的原理。（ ）
（5）分别利用左上角1、3、6个系数重建图像，计算相应的SAD，并由此分析直流和低频系数的重要性。
-Known brightness of two different image data block is as follows: (1) Principles of analysis of DCT, the DCT method, program and calculate the corresponding DCT coefficient, analysis of distribution coefficients. (2) quantitative analysis based on visual characteristics of the distribution of long-form features step-by-step to complete the DCT coefficient quantization. (3) the use of Z-scan output data to achieve statistical encoding, the formation of Video stream. (4) the use of the reconstructed image brightness IDCT data to calculate the SAD size, analysis of the causes of errors and the use of DCT for the principle of data compression. () (5), respectively, a factor of 1,3,6 using the upper left corner of the reconstruction of images, calculating the corresponding SAD, and the resulting analysis of DC and the importance of low-frequency coefficients. Platform: |
Size: 1024 |
Author:张元 |
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Description: 一種基于塊樹結構的SPIHT數字圖像壓縮算法: 在分析圖像經過小波變換后所具有的特性的基礎上,提出了一種改進的SPIHT算法.由于低頻系數占據圖像的百分之九十以上的能量,在圖像的重構中十分重要,所以,對這些系數不進行壓縮而直接傳輸 而最高頻系數相對不重要,所以不做處理,只在圖像重構時以指定的數值予以重構,因此不僅提高了圖像的質量,同時提高了圖像的壓縮率.在具體的算法中,提出了塊樹的結構,減少了算法所需的內存,拓寬了算法的應用范圍.-A tree structure based on the SPIHT block of digital image compression algorithm: After the analysis of images after the wavelet transform features, based on a modified SPIHT algorithm. Due to the low frequency coefficient images occupy more than 90 percent of energy in image reconstruction is very important, so these factors do not directly transfer compression The most high-frequency coefficient is relatively unimportant, so no treatment, only when the image reconstruction be designated numerical reconstruction therefore not only improve the image quality, while improving the image compression ratio. algorithms in specific, the proposed block-tree structure, the algorithm to reduce memory requirements and broaden the scope of application of the algorithm. Platform: |
Size: 273408 |
Author:jason.. |
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Description: 基于像素域的改進的SPIHT算法:分層樹的集分割算法是一種簡單、有效的嵌入式零樹編碼算法.在算法的基礎上提出了一種基于空域的改進方法.首先將圖像的偶數裂像素減去相鄰兩奇數列的均值,形成分裂圖像.然后將分裂圖像的奇數列提取出來作為主圖像,將偶數列提取出來作為幅圖像.最后將主幅圖像以合適的權值分別進行壓縮-Pixel-based domain improved SPIHT algorithm: the set partitioning in hierarchical tree algorithm is a simple, efficient embedded zerotree coding algorithm. In the algorithm based on an improved method based on the airspace. First of all, the even split the image pixels minus the two adjacent odd-numbered out of the mean to form a split image. and then split the images out of the odd-numbered extracted as the main image will be extracted out as even-numbered images. Finally, the main image to the right to appropriate values for compression Platform: |
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Author:jason.. |
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Description: 本论文首先系统地介绍了视频压缩编码的基本原理和方法，以及各国际标准
化组织提出的压缩标准；其次分析了JPEG和MPEG-4的主要技术，据此提出
MPEG-4简单框架编码器的软件实现方案，给出流程图，在VC++环境下用C语言
程序实现了JPEG压缩及MPEG-4简单框架的视频压缩功能，采用测试序列验证
无误，并对两种标准的压缩比进行试验对比，突出压缩的关键技术为DCT和运动
估计算法；接着深入研究了DCT变换、运动估计和补偿算法并进行了优化改进，
给出了用于快速匹配块的自适应十字模式搜索算法，并给出了对各种块匹配估计
算法的仿真结果。然后详细介绍了TI公司TMS320C6711DSP的软硬件特性，并
在此基础上提出系统的硬件实现方案。接着介绍了基于系统软硬件环境的移植问
题和优化方法，并针对算法移植和仿真过程中的问题进行了说明。
最后就课题设计过程中研究的结果予以总结，并阐述了以后课题研究的要点。-In this thesis,an introduction to video compression principal,methods and central
international video coding standards is done firstly.Then analyzing the core techniques
of JPEG and MPEG-4 and proposing a scheme of MPEG-4 SP encoder,the coding
function of JPEG and MPEG-4 is achieved in C successfully with test sequence Then
compare the compressed ratio of two standards,point out the key of compression is DCT
and Motion Estimation algorithm.Afterwards,studying the DCT/Motion
Estimation/Motion Compensation algorithm in detail and giving an adaptive rood
pattern search for fast Block-Matching motion estimation.Then the simulation of several
motion estimation algorithms based block-matching is given.Accordingly,a scheme of
a DSP-based video compression system is put forward,with the features of TI’s
TMS320C6711 DSP.At last,the transplant and optimization are considered on the basis
of soft and hard environments,also the simulation process.
In the end,the summarization about the Platform: |
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Author:father2002 |
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Description: 一系列展示图像压缩技术的源代码。包括有：使用块截断编码的图像压缩(Block Truncation)、基于高斯金字塔变换的图像压缩(Gaussian Pyramids)、基于离散余弦变换对图像压缩(Discrete Cosine Transform)、基于奇异值分解(SVD)的图像压缩(Singular Value Decomposition)。给出的代码还可以用于2D图像噪声消除。-Image Compression
A collection of simple routines for image compression using different techniques.
BTCODE:
Image compression Using Block Truncation Coding.
PYRAMID:
Image compression based on Gaussian Pyramids.
DCTCOMPR:
Image compression based on Discrete Cosine Transform.
IMCOMPR:
Image compression based on Singular Value Decomposition.
The given codes can be also used in 2D noise suppression.
Notes:
The function "conv2fft" performs a 2D FFT-based convolution.
Type "help conv2fft" on Matlab command window for more informations. Platform: |
Size: 56320 |
Author:依米 |
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Description: 摘 要：基于块的运动估计是视频压缩国际标准中广泛采用的关键技术。在对目前运动估计快速块匹配算法研究的基础上，描述了运动估计
的原理；揭示 了在图像质量、搜索速度和压缩码率等方面提高算法效率时存在的3 类主要问题 ：初始搜索点的选择、匹配准则和搜索策略 ；
分另 q 阐述了目前常用的解决这3 类问题的方法，并进行了比较和分析 ；提出了对运动估计算法的一些展望。-Abstract: The block-based motion estimation is a video compression standard is widely used in international key technology. In the current fast block matching motion estimation algorithm based on the principles described in the motion estimation revealed in image quality, the search speed and compression rate and so improve the efficiency exists in the 3 principal issues: the initial search point selection, matching criteria and search strategies points q describes the other currently used to solve the 3 class problem, and compared and analyzed proposed motion estimation algorithm on some prospects. Platform: |
Size: 182272 |
Author:zjl |
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Description: Abstract- H.264/AVC is becoming a popular video codec for
its better compression ratio, lower distortion and applicability
to portable electronic devices. Thus, issues of copyright
protection appropriate for this standard become very
important. In this paper, a new blind SVD (Singular Value
Decomposition) - DCT combined video watermarking scheme
for the ".264 standard is proposed. The proposed method is a
blind watermarking algorithm as the hidden information can be
extracted without the original video and the original singular
values. To reduce visual quality degradation caused by
coefficients modifying, the perceptual model and block selection
mechanism are introduced to control the modification strength.
The performance of the proposed algorithm is evaluated with
respect to imperceptibility, robustness and data payload.
Experimental results reveal that the proposed scheme achieves
enough robustness while preserving the perceptual quality.-Abstract- H.264/AVC is becoming a popular video codec for
its better compression ratio, lower distortion and applicability
to portable electronic devices. Thus, issues of copyright
protection appropriate for this standard become very
important. In this paper, a new blind SVD (Singular Value
Decomposition)- DCT combined video watermarking scheme
for the ".264 standard is proposed. The proposed method is a
blind watermarking algorithm as the hidden information can be
extracted without the original video and the original singular
values. To reduce visual quality degradation caused by
coefficients modifying, the perceptual model and block selection
mechanism are introduced to control the modification strength.
The performance of the proposed algorithm is evaluated with
respect to imperceptibility, robustness and data payload.
Experimental results reveal that the proposed scheme achieves
enough robustness while preserving the perceptual quality. Platform: |
Size: 486400 |
Author:lie |
Hits:
Search - block based compression