Description: 论文包括两个方面：离散余弦变换（DCT）的快速算法及滤波器实现结构，于波变换域图像门槛降噪。离散余弦变换是广泛应用于信号处理、图像处理领域的重要工具之一，己经被多个国际标准所接受，如JPEG、MPEG、H．263等。DCT应用到实际系统中的前提是具有能够快速实现的算法，自从1977第一个真正的DCT快速算法出现以来，寻求更快、更规则、更简单的DCT快速算法一直是信号处理领域的一个研究方向。论文针对应用中对DCT长度的-papers include two aspects : discrete cosine transform (DCT) algorithm for the rapid and filter structure, in the wavelet transform domain image noise threshold. Discrete Cosine Transform is widely used in signal processing, image processing area of one of the important tools, has been a number of international standards to be accepted, such as JPEG, MPEG, H. 263, and so on. DCT applied to the actual system is the prerequisite to achieving rapid algorithm Since 1977 the first real fast DCT algorithm since its emergence, seek faster, more rules, DCT more simple fast algorithm signal processing has been an area of research. Application papers against the length of the DCT Platform: |
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Description: 论文包括两个方面：离散余弦变换（DCT）的快速算法及滤波器实现结构，于波变换域图像门槛降噪。离散余弦变换是广泛应用于信号处理、图像处理领域的重要工具之一，己经被多个国际标准所接受，如JPEG、MPEG、H．263等。DCT应用到实际系统中的前提是具有能够快速实现的算法，自从1977第一个真正的DCT快速算法出现以来，寻求更快、更规则、更简单的DCT快速算法一直是信号处理领域的一个研究方向。论文针对应用中对DCT长度的-papers include two aspects : discrete cosine transform (DCT) algorithm for the rapid and filter structure, in the wavelet transform domain image noise threshold. Discrete Cosine Transform is widely used in signal processing, image processing area of one of the important tools, has been a number of international standards to be accepted, such as JPEG, MPEG, H. 263, and so on. DCT applied to the actual system is the prerequisite to achieving rapid algorithm Since 1977 the first real fast DCT algorithm since its emergence, seek faster, more rules, DCT more simple fast algorithm signal processing has been an area of research. Application papers against the length of the DCT Platform: |
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Description: 使用二维离散余弦变换(DCT)进行图象压缩。原始图象被转换成为8*8大小的块进行压缩和重构。 Cnum:为压缩时保留的系数的个数 MSM:均方误差压缩应该做到在最合理的近似原图象的情况下使用最少的系数。函数：dctmtx:返回一个n*n阶DCT变换 blkproc:对图象进行不同的块处理。 im2col:重排图象块为矩阵列。注意：只适用于灰度图象。-The use of two-dimensional discrete cosine transform (DCT) for image compression. Original image is converted to become the size of 8* 8 block compression and reconstruction. Cnum: reservations for the compression factor of the number of MSM: mean square error compression should be done in the most reasonable approximation of the original image using the least coefficient. Function: dctmtx: returns an n* n-order DCT transform blkproc: image processing of different blocks. im2col: rearrangement of the matrix block out images. Note: only applicable to grayscale images. Platform: |
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Author:hff |
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Description: 基于DCT域的图像数字水印技术：
摘要：数字水印技术作为数字媒体版权保护的有效办法，近年来在国内外引起了人们极大的兴趣。作者采用了DCT离散余弦变换的算法，对图像这种多媒体数字作品进行了数字水印的嵌入和检测研究。并且使用了高效实用的编程工具MATLAB来介绍了一种DCT域的图像数字水印嵌入和提取的实例，并且在最后对嵌入水印的图像进行了攻击实验，验证了该算法的鲁棒性和不可见性。-Based on the DCT domain image watermarking techniques: Abstract: Digital watermarking of digital media technology as an effective means of copyright protection, in recent years both at home and abroad has aroused great interest. The author adopted the DCT discrete cosine transform algorithms, the image of this multi-media digital works for the digital watermark embedding and detection research. And the use of efficient MATLAB programming tools useful to introduce a DCT domain image watermarking embedding and extraction examples, and in the final of the embedded watermark image of the attack experiments verify the robustness of the algorithm and non- Visibility. Platform: |
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Author:绯村剑心 |
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Description: 我一个师兄毕业是编写的图像融合程序,一定有人需要的-I am a senior graduating from the preparation of the image fusion procedure, a certain someone in need Platform: |
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Author:龚振宇 |
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Description: DCT1.m为一维离散余弦变换exp22.m为对一幅灰度图像进行离散余弦变换
exp23.m为对一幅彩色图像进行离散余弦变换-DCT1.m for the one-dimensional discrete cosine transform exp22.m for a gray image exp23.m discrete cosine transform for the color of an image discrete cosine transform Platform: |
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Author:李沁 |
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Description: DCT用于掌纹识别的word论文文档，比pdf更容易阅读编辑和引用，供大家学习和交流-The discrete cosine transform is a classical image processing technique, and the discriminant analysis is a commonly used image feature extraction technique. These two techniques are effectively combined in the paper, and a new palmprint feature extraction approach is proposed. After performing discrete cosine transform on the palmprint images, the proposed approach first uses a two-dimensional separability judgment to select the frequency bands with favorable separability. Then from the selected bands, it extracts the discriminant features by using an improved Fisherface method. The experimental results on the public palmprint image database demonstrate the effectiveness of the proposed approach. Platform: |
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Author:小哈 |
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Description: 随着人机交互界面的日益复杂,嵌入式系统显示复杂图象的应用也越来越多,而未经过压缩的图象占用的存储空间很大,压缩后的图象存储空间大幅度减少,而嵌入式系统在进行图象解码时会用到占用大量计算资源的 DCT算法,本文提出了一种应用于嵌入式系统的 8 ×8离散余弦变换算法的优化及实现方法。-With the increasing complexity of man-machine interface, embedded system shows a complex picture of the applications are more and more compressed image without the storage space occupied by large, compressed image storage space substantially reduced, embedded systems will be used during image decoding take up a lot of computing resources DCT algorithm, this paper presents an embedded systems used in 8 × 8 discrete cosine transform algorithm optimization and realization method. Platform: |
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Author:康云 |
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Description: 本文提出一种在原始视频DCT(离散余弦变换)与SVD(奇异值分解)域自适应嵌入水印的算法。算法首先将视频流分割成一个个场景,场景中的视频图像被变换到DCT-SVD域中,水印量化嵌入在最大奇异上,实现了水印盲检测。同时实验证明该算法在满足透明性要求下也满足一定的鲁棒性要求,能够抵抗低通滤波、中值滤波、椒盐噪声、高斯噪声、H.264压缩攻击以及统计攻击和帧剪切等攻击。-This paper presents an original video in the DCT (Discrete Cosine Transform) and SVD (singular value decomposition) algorithm for adaptive watermark embedding. Firstly, a video stream is divided into scenes, scenes of the video image is converted to the DCT-SVD domain, the watermark embedded in the largest singular quantification, the realization of the watermark signal. Furthermore, the experiments show that the algorithm meet the transparency requirements are met under certain robustness requirements, can resist the low-pass filtering, median filtering, salt and pepper noise, Gaussian noise, H.264 compression attacks and attacks and frame shear statistics attack. Platform: |
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Author:久久 |
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Description: Discrete Cosine Transform (DCT) and quantization are two critical parts in image encoding. By discussing how coefficients retaining and quantization step selection influence the quality of the reconstructed image, this homework helps to understand the procedure of encoding of an image in the international video standards (JPEG, H.261, ...). Platform: |
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Author:pgorangel |
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Description: this the code for compression of an image using discrete cosine transform-this is the code for compression of an image using discrete cosine transform Platform: |
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Author:nitharsana |
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Description: 1了解图像变换的意义和手段；
2熟悉离散傅里叶变换、离散余弦变换、离散小波变换的基本性质；
3熟练掌握图像变换的方法及应用；
4通过实验了解二维频谱的分布特点；
5通过本实验掌握利用MATLAB编程实现数字图像的变换。
-An understanding of the meaning and image transformation means 2 familiar with the discrete Fourier transform, discrete cosine transform, discrete wavelet transform the fundamental nature 3 master image transformation method and its application four experiments to understand the distribution characteristics of two-dimensional spectrum 5 Through this study, MATLAB programming master the use of digital image transformation. Platform: |
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Author:wanghui |
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Description: 作为信息隐藏的重要分支，数字水印是一种有效的数字产品版权保护和数据安全维护技术。近年来数字水印技术成为了信息安全领域的研究热点，也得到了较大的发展。基于变换域的水印技术是目前研究的热点和重点。本文系统介绍了数字水印的原理和应用方法，概要介绍了数字水印的几种主流算法，并重点研究了一种基于离散余弦变换(DCT)数字图像水印算法，并借助 MATLAB编程工具，实现数字水印的嵌入和提取仿真，以及为测试鲁棒性而对水印图像进行攻击实验。-As an important branch of information hiding, digital watermarking is an effective copyright protection of digital products and data security maintenance technology. In recent years, digital watermarking has become a hot research field of information security, has also been considerable development. Transform domain watermarking technique based on the current research focus and focus. This system describes the principles and applications of digital watermarking methods, an overview of several mainstream digital watermarking algorithms, and focus on a discrete cosine transform (DCT) digital image watermarking, and with the MATLAB programming tools, digital watermark embedding and extraction simulation, as well as test the robustness of the watermark image on the attack experiments. Platform: |
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Author:yang cheng |
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Description: 基于DCT域的图像数字水印技术： 摘要：数字水印技术作为数字媒体版权保护的有效办法，近年来在国内外引起了人们极大的兴趣。作者采用了DCT离散余弦变换的算法，对图像这种多媒体数字作品进行了数字水印的嵌入和检测研究。并且使用了高效实用的编程工具MATLAB来介绍了一种DCT域的图像数字水印嵌入和提取的
-DCT domain of image-based digital watermarking technology: Abstract: digital watermarking technology as an effective way of copyright protection of digital media, both at home and abroad in recent years has aroused great interest of the people. The DCT discrete cosine transform algorithm of digital watermark embedding and detection, the image of this multimedia digital works. Practical and efficient programming tools and use MATLAB to introduce a DCT domain image watermarking embedding and extracting Platform: |
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Author:赵杰 |
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Description: 实现图像处理中，实现对一幅灰度图像的快速傅立叶变换,并求其变换后的系数（幅度）分布，同时实现对一幅图像做离散余弦变换,选择适当的DCT系数阈值对其进行DCT反变换 -Realize image processing, to achieve the fast Fourier transformation of a grayscale image, and determine the distribution of its transform coefficients (amplitude), while achieving a discrete cosine transform of an image do, to select the appropriate threshold value of the DCT coefficients to the DCT inverse transform Platform: |
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Author:茗汀 |
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Description: 盲水印提取时不需要参考原始载体图像,在信息隐藏、版权保护等方面具有更广泛的应用前景。提出的盲水印算法在分块离散余弦变换(DCT)和离散小波变换(DWT)的基础上,利用关系双方DCT系数和DWT系数在受到攻击时具有相同变化趋势的特点,采用关系嵌入和量化嵌入的自适应选择嵌入策略,较大幅度地提高了盲水印提取的鲁棒性。同时在量化嵌入中采用抖动调制,实现了水印透明性和鲁棒性调节的便捷性。大量仿真实验结果表明该算法对噪声干扰、低通滤波、JPEG压缩、对比度增强等攻击有很好的鲁棒性和透明性。关键词 数字水印盲水印关系嵌入量化嵌入离散余弦变换离散小波变换
按这篇文章的算法，自己编的matlab,没有攻击时水印提取率为1，加水印后图像PSNR有45+，。有攻击后提取率也有0.9+。-Blind watermark extraction can be fulfilled without referring to the original host image. Therefore it hasmuch
prospective applications in the fields of information hiding and copyright protection. Based on blocking Discrete Cosine
Transform (DCT) and blocking DiscreteWaveletTransform (DWT), the proposed blind watermarking algorithm uses an
embedding strategy of adaptively selecting either relationship embedding or quantization embedding. The relationship em-
bedding comes from the observation thatboth themagnitudes of coefficients concerned in the relationship usually have thesame change trend when the image is attacked. This strategy remarkably improves the robustness ofwatermark extraction.In addition, dithermodulation is used in quantization embedding, bywhich the tradeoff between transparency and robus-tness ofwatermarking can be easily adjusted. Simulation results show that the algorithm is fairly robust against the attacks such as noise, filtering, compression, and contrast Platform: |
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Author:CXF |
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Description: This the first comprehensive treatment of the oretical aspects of the discrete cosine transform (DCT), which is being recommended by various standards organizations, such as the CCITT, ISO etc., as the primary compression tool in digital image coding. The main purpose of the book is to provide a complete source for the user of this signal processing tool, where both the basics and the applications are detailed. An extensive bibliography covers both the theory and applications of the DCT. The novice will find the book useful in its self-contained treatment of the theory of the DCT, the detailed description of various algorithms supported by computer programs and the range of possible applications, including codecs used for teleconferencing, videophone, progressive image transmission, and broadcast TV. The more advanced user will appreciate the extensive references. Tables describing ASIC VLSI chips for implementing DCT, and motion estimation and details on image compression boards are also provided.-This is the first comprehensive treatment of the theoretical aspects of the discrete cosine transform (DCT), which is being recommended by various standards organizations, such as the CCITT, ISO etc., as the primary compression tool in digital image coding. The main purpose of the book is to provide a complete source for the user of this signal processing tool, where both the basics and the applications are detailed. An extensive bibliography covers both the theory and applications of the DCT. The novice will find the book useful in its self-contained treatment of the theory of the DCT, the detailed description of various algorithms supported by computer programs and the range of possible applications, including codecs used for teleconferencing, videophone, progressive image transmission, and broadcast TV. The more advanced user will appreciate the extensive references. Tables describing ASIC VLSI chips for implementing DCT, and motion estimation and details on image compression boards Platform: |
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Author:张超 |
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