Description: 1.了解离散傅立叶变换及离散余弦变换的基本原理;
2.掌握进行FFT及逆变换的方法;
3.了解图像在频域中处理方法,应用MATLAB语言作简单的低通滤波器。
-1. Understand the discrete Fourier transform and discrete cosine transform the basic principle; 2. master for FFT and inverse transform; 3. understanding of image processing in the frequency domain method, MATLAB language for simple low-pass filter. Platform: |
Size: 16483 |
Author:小春 |
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Description: Image Compression
A collection of simple routines for image compression using different techniques.
图象压缩的不同方法
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: 10228 |
Author:王云云 |
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Description: VC编写的高效的图象2D快速傅立叶正变换程序,编译通过.适合256色bmp图象变换.效果和matlab的fft2()没法比,但是程序值得借鉴.适合图象处理初学者,有助于理解傅立叶变换在图象处理中的重要作用.-VC efficient preparation of the image is 2D fast Fourier transform procedures compile. Bmp for 256-color image transformation. Results and Matlab fft2 () no match for, but the procedure is worth learning from. Image processing for beginners, helps to understand Fourier transform in the image processing an important role. Platform: |
Size: 84992 |
Author:李安定 |
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Description: 1.了解离散傅立叶变换及离散余弦变换的基本原理;
2.掌握进行FFT及逆变换的方法;
3.了解图像在频域中处理方法,应用MATLAB语言作简单的低通滤波器。
-1. Understand the discrete Fourier transform and discrete cosine transform the basic principle; 2. master for FFT and inverse transform; 3. understanding of image processing in the frequency domain method, MATLAB language for simple low-pass filter. Platform: |
Size: 16384 |
Author:小春 |
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Description: Matlab_基于FFT的图像配准
粗估算两幅图像之间的平移差,返回水平方向平移差到xtran,返回垂直方向平移差到ytran
用在图像配准中的粗匹配中,对噪声、图像中物体发生运动等极为鲁棒!-FFT-based Matlab_ Image Registration rough estimate of the translation between two images, poor, poor translation to return to the horizontal direction to xtran, to return to the vertical direction to the poor translation ytran image registration used in the coarse matching of noise, image movement of objects, such as occurred in a very robust! Platform: |
Size: 135168 |
Author:yol |
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Description: The frequency domain plays an important role in image
processing to smooth, enhance, and detect edges of images. Although
image data typically does not include imaginary values, the fast Fourier
transform (FFT) has been used for obtaining spectra. In this paper,
the fast Hartley transform (FHT) is used to transform two-dimensional
image data. Because the Hartley transform is real valued, it does
not require complex operations. Both spectra and autocorrelations of
two-dimensional ultrasound images of normal and abnormal livers were
computed. Platform: |
Size: 4096 |
Author:archit |
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Description: 本实验要求开发一个2-D FFT程序包,使其可以应用于后续的几个实验。这个程序需要完成的功能是用因子(-1)^(x+y)乘以输入图像以实现滤波的中心变换,并还要求用一个实矩阵乘以一个复数矩阵通过调用两个图像的乘法程序来实现对应元素的相乘,同时计算反傅立叶变换,得到的结果乘以(-1)^(x+y)并取其实部最后计算频谱。实验中用到傅立叶变换的基本公式,通过实验我们可以更加深刻的理解频域滤波的基础。-The experiment calls for the development of a 2-D FFT package so that it can be applied to a number of follow-up experiment. This process needs to be done is to factor the function (-1) ^ (x+ y) multiplied by the input image to achieve the center of filter change, and also requires a real matrix multiplied by a complex matrix by calling the two images of the multiplication process to achieve multiplication of the corresponding elements, calculating the anti-Fourier transform at the same time, the result multiplied by (-1) ^ (x+ y) and check the final calculation of the Department of the spectrum in fact. Fourier transform experiment used the basic formula, we can experiment more profound understanding of the basis of frequency domain filtering. Platform: |
Size: 142336 |
Author:jhm |
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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: 二维傅里叶变换,对图像进行二维傅里叶变换处理-Two-Dimensional Fast Fourier Transform
The purpose of this project is to develop a 2-D FFT program "package" that will be used
in several other projects that follow. Your implementation must have the capabilities to:
(a) Multiply the input image by (-1)x+y to center the transform for filtering.
(b) Multiply the resulting (complex) array by a real function (in the sense that the
the real coefficients multiply both the real and imaginary parts of the transforms).
Recall that multiplication of two images is done on pairs of corresponding elements.
(c) Compute the inverse Fourier transform.
(d) Multiply the result by (-1)x+y and take the real part.
(e) Compute the spectrum. Platform: |
Size: 1024 |
Author:solo |
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Description: Pass the Images Through Optics -- Use a Gaussian "Aperture Function"
This code segement can use a measured aperture function just as easily - simply replace the next five lines by "load measured_aperture" where measured_aperture is the measured function strored in ASCII and the data stored in the file measured_aperture.mat is a MATLAB .mat file that contains the matrix apfunction. (in MATLAB type "help load" for how to use load and look at the c and fortran code that shows how to read and write MATLAB .mat files).
(Note: When the Point Spread Function is Gaussian, then so is the Aperture function)
To simulate the effect of the tracker optics, each of the movie frames is now blurred using a 2-D FFT (Fast Fourier Transform). The first frame of the resulting image is shown in Figure 1.
- Pass the Images Through Optics -- Use a Gaussian "Aperture Function"
This code segement can use a measured aperture function just as easily - simply replace the next five lines by "load measured_aperture" where measured_aperture is the measured function strored in ASCII and the data stored in the file measured_aperture.mat is a MATLAB .mat file that contains the matrix apfunction. (in MATLAB type "help load" for how to use load and look at the c and fortran code that shows how to read and write MATLAB .mat files).
(Note: When the Point Spread Function is Gaussian, then so is the Aperture function)
To simulate the effect of the tracker optics, each of the movie frames is now blurred using a 2-D FFT (Fast Fourier Transform). The first frame of the resulting image is shown in Figure 1.
Platform: |
Size: 1024 |
Author:sabah_altaie |
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Description: 傅立叶变换是数字图像处理中应用最广的一种变换,其中图像增强、图像复原和图像分析与描述等,每一类处理方法都要用到图像变换,尤其是图像的傅立叶变换。常用的图像增强技术可分为基于空域和基于变换域的两类方法。最常用的变换域是频域空间。在频域空间,图像的信息表现为不同频率分量的组合。如果能让某个范围内的分量或某些频率的分量受到抑制而让其他分量不受影响,就可以改变输出图像的频率分布,达到不同的增强目的。
4、高通滤波- 锐化
-Fourier transform in digital image processing is a transformation, which is the most widely used, including image enhancement, image restoration and image analysis and description. Each method is used for image processing, especially the image transform. This paper describes the digital image transform and gives the MATLAB program. Then, using FFT, realizes the image smoothing by using the low-pass filter and images sharpening by using the high-pass filter. Platform: |
Size: 23552 |
Author:李慕白 |
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Description: the code conducts the image compression of the gray scale image up to 90 using 4 algos fft wavelet pca and cosine transform-the code conducts the image compression of the gray scale image up to 90 using 4 algos fft wavelet pca and cosine transform Platform: |
Size: 1024 |
Author:vicky |
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Description: 使用matlab的gui界面实现图像缩放旋转功能,FFT,DCT,等图像变化变换,并绘出直方图-Use the matlab gui interface for image scaling rotation, FFT, DCT, and other changes in the image transformation, and draw the histogram Platform: |
Size: 557056 |
Author:jason |
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Description: 在下面给出的图1中寻找小写字母a。
要求
1. 程序输入图像1,输出表征字母a大概位置的图像和字母a出现的次数;
2. 使用二维fft实现,建议自己编写二维fft函数,不使用matlab自带的fft2函数。-Given below in figure 1 in search for small letters a.
requirements
1. The input image 1, output characterization of the letters a general location image and the letters a in the frequency of
2. Use 2 d FFT realize, suggested that his writing 2 d FFT function, do not use matlab bring fft2 function.
Platform: |
Size: 3072 |
Author:潘多 |
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Description: 基于MATLAB实现了极坐标下的傅里叶变换,对一个给定 n×n 的二维信号,其计算复杂度等价于笛卡尔坐标下的2D-FFT,可广泛应用于图像处理和分析。-A fast high accuracy Polar FFT algorithm is given in the software package written in MATLAB. For a given 2D signal of size n×n, the algorihtm s complexity is just like in a Cartesian 2D-FFT, which can be used widely in image processing and analysis. Platform: |
Size: 579584 |
Author:周清保 |
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Description: (1)在MATLAB环境下编写FFT算法(不调用系统现有函数);
(2)实现对选定图片进行FFT计算、还原(IFFT计算),并与系统FFT函数做对比,进行分析;
(3)设计GUI界面。-(1) the preparation of the FFT algorithm (do not call the system existing function) in MATLAB environment
(2) to achieve the selected image to the FFT calculation, reduction (IFFT computing), and FFT functions to do comparison with the system for analysis
(3) Design GUI interface. Platform: |
Size: 183296 |
Author:黄培哲 |
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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.
Notes:
The function conv2fft performs a 2D FFT-based convolution.
Type help conv2fft on MATLAB command window for more informations.-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: 9216 |
Author:keyvan |
Hits: