Description: 提供了关于图像抽样、量化、均匀化、规定化及获得图像位面图的程序-provided on the image sampling, quantization, homogenization, and provides access to images of surface spaces of the processes Platform: |
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Author:王严 |
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Description: 一张图片是之前用摄像机采集的，另一张图片是经过离散沃尔什变换再量化编码压缩后又解压所得，能看出区别吗？呵呵。flik.m是原图，newflik.m是新图。
附上所有MATLAB源程序，有兴趣的话，你也可以用这几个程序对自己的照片“加工”一番。以下6个程序分别保存为6的m文件，文件名与下面给出的一致。待“加工”图片应该存放在Matlab的Work目录下。-Before a picture is collected by the camera, another picture is the result of discrete Walsh transform and then re-quantization coding compression decompression income, you can see the difference? Ha ha. flik.m is the image, newflik.m is a new map. MATLAB source code attached to all interested, you can also use these procedures on their own photo processing of something. The following six procedures were saved as 6 m file, the file name is given with the following consensus. To be processing picture should be stored in Matlab s Work directory. Platform: |
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Author:余海风 |
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Description: 基于标量量化的图像多描述编码（MDSQ）是提高信息传输质量的一种有效方法,本程序利用Matlab 工具在处理矩阵上的灵活性,实现了MDSQ 算法, 并通过解码后的图像证明该方法良好的多描述性能。-Scalar quantization-based image multiple description coding (MDSQ) is to improve the quality of information transmission of an effective method, the procedures for the use of Matlab tool flexibility matrix treatment, realized MDSQ algorithm, and through decoded images show that the method good performance of multiple description. Platform: |
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Author:shanyingying |
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Description: 摘 要
文章以空间监控系统为背景,深入研究了JPEG图像压缩标准的实现方法,并基于FPGA对其进行了实现和优化。文中给出了详细的实现方法和优化过程,测试表明达到了很好的效果。
简单介绍了有损静态图像压缩当前有两种比较流行的标准JPEG和JPEG2000。说明了用JPEG方法压缩的原因。
介绍JPEG基本原理：JPEG对灰度图像的压缩处理过程主要包括:图像分割,离散余弦变换(DCT),量化(Quantization),“Z”形排序(Zigzag Scan),差分脉冲编码调制(Differential Pulse Code Modulation,DPCM)对直流系数(DC),行程长度编码(Run-Length Encoding,RLE)对交流系数(AC),霍夫曼(Huffman)编码等。
JPEG标准的特点是离散余弦变换。
比较详细介绍压缩系统的构成和实现。实现提及步骤， JPEG压缩模块设计和编码模块实现细节。
-Abstract
Article in the space monitoring system for the background, in-depth study of the JPEG image compression standard implementation methods and carried out based on FPGA implementation and optimization. In this paper, a detailed method of implementation and optimization of the process, testing showed that to achieve good results.
Easy introduction of harmful static image compression has two kinds of comparisons that the current popular standard JPEG and JPEG2000. Illustrated by the reasons for JPEG compression method.
JPEG introduce the basic principles: JPEG compression of gray-scale image processing include: image segmentation, discrete cosine transform (DCT), quantization (Quantization), "Z"-shaped sort (Zigzag Scan), differential pulse code modulation (Differential Pulse Code Modulation, DPCM) on the DC coefficient (DC), Run Length Encoding (Run-Length Encoding, RLE) of the exchange coefficient (AC), Hoffman (Huffman) coding.
JPEG standard is characterized by discrete Platform: |
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Author:压子 |
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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: |
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Author:张元 |
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Description: This a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
-This is a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
Platform: |
Size: 1024 |
Author:Ho Joon Lee |
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Description: This a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
-This is a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
Platform: |
Size: 3072 |
Author:Ho Joon Lee |
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Description: This a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
-This is a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
Platform: |
Size: 128000 |
Author:Ho Joon Lee |
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Description: This a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
-This is a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
Platform: |
Size: 189440 |
Author:Ho Joon Lee |
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Description: This a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
-This is a JPEG encoding & decoding program of still image. It does not use level shifting. Discrete Cosine transform (DCT) is performed both by classical & Chen s Flowgraph methods. Predefined JPEG quantization array & zigzag order are used here. RUN - LEVEL coding is used instead of Huffman coding. Compression ratio is compared for each DCT method. Effect of coarse and fine quantization is also examined. The execution time of 2 DCT methods is also checked. In addition, most energatic DCT coefficients are also applied to examine the effect in MatLab 7.4.0 R2007a. Input is 9 gray scale pictures & output is 9*9=81 pictures to compare. Blocking effect is obvious.
Platform: |
Size: 95232 |
Author:Ho Joon Lee |
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Description: Matlab矢量量化图像压缩程序
矢量量化VQ，是一个常见的压缩技术。Linde, Buzo, and Gray 提出了基于
训练序列的Vector Quantization (VQ)算法。-Matlab vector quantization image compression procedures for vector quantization VQ, is a common compression technology. Linde, Buzo, and Gray proposed based on training sequence of Vector Quantization (VQ) algorithm. Platform: |
Size: 47104 |
Author:adu |
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Description: Matlab矢量量化图像压缩程序
矢量量化VQ，是一个常见的压缩技术。Linde, Buzo, and Gray 提出了基于
训练序列的Vector Quantization (VQ)算法。-Matlab vector quantization image compression procedures for vector quantization VQ, is a common compression technology. Linde, Buzo, and Gray proposed based on training sequence of Vector Quantization (VQ) algorithm. Platform: |
Size: 47104 |
Author:adu |
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Description: 实现对视频图像的游程编码和解码。过程包括：二维DCT变换、量化及游程编码。
一般来讲对于视频的I帧进行恢复，其信噪比可达到38DB以上。-Implementation of the video image encoding and decoding run-length. Process includes: two-dimensional DCT transform, quantization and run-length encoding. In general, I frame for the video resume, the signal to noise ratio can reach more than 38DB. Platform: |
Size: 7168 |
Author:zrs |
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Search - quantization for image in matlab