Rank: 269 based on 234 downloads (last 30 days) and 10 files submitted
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Frederico D'Almeida

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UnB - Universidade de Brasilia

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Files Posted by Frederico View all
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26 Mar 2004 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida coherenceenhancing di..., nonlinear diffusion, anisotropic diffusion, filtering 78 36
  • 4.63636
4.6 | 33 ratings
18 Mar 2003 DTMF Detector Detects DTMF tones in audio by Goertzel algorithm. Author: Frederico D'Almeida dtmf, communications, goertzel, audio, algorithm 13 1
21 Feb 2002 General Extra Toolbox Generic functions for matrix manipulation, image processing, etc. Author: Frederico D'Almeida fft, index, matrices, image manipulation, matrix, max 8 4
  • 2.5
2.5 | 4 ratings
18 Feb 2002 Shrink Eliminates image borders. Author: Frederico D'Almeida morphology, segmentation, shrink border image 6 0
18 Feb 2002 Posterize Reduces the number of colors of an image. Author: Frederico D'Almeida color, posterize reduce colo... 11 0
Comments and Ratings on Frederico's Files View all
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15 Nov 2011 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida li, ray

good,thanks.
28 Jan 2011 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida Yuan, Ding

Hi Frederico,

I am translating your matlab code in to IDL, I find that in the convolution step ('gsderiv.m'), the gaussian kernel is not normalized. It is done in 1D 'kernel=kernel/sum(kernel)', however, it is important that you do it like this:
kernel_grid=meshgrid(kernel_index,kernel_index)
kernel = exp(-.5*(kernel_grid./sigma).^2)
kernel=kernel/sum(kernel)

then you do convolution

 
22 Dec 2010 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida Malviya, Aadarsh

theres some problem in linear diffusion. I am getting colored images in nonlinear.

How can i reduce the diffusion and I am unable to undrstand the inputs takn can any one help me please aadarshmalviya@gmail.com
18 Oct 2010 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida À=, Xiuli

nice work!
but there is a tiny question, the function name of 3d nonlinear diffusion should be nldif3, not nldif, this maybe a typo.
27 Sep 2010 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida zaki, mops

there is bug in almost all file for example
Input argument "x" is undefined.
in fileaosiso at 16
y = zeros(size(x));

 Input argument "x" is undefined.
in file aosiso1 at 16
y = zeros(size(x));
i cant under stand why these are are coming as im using the higher version of matlab. R14
Top Tags Applied by Frederico
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filtering, morphology, 2d, algorithm, anisotropic diffusion
Files Tagged by Frederico View all
  • 1 - 5 of
  • 10
Updated   File Tags Downloads
(last 30 days) 		Comments Rating
26 Mar 2004 Nonlinear Diffusion Toolbox Set of functions to perform nonlinear diffusion on images. Author: Frederico D'Almeida coherenceenhancing di..., nonlinear diffusion, anisotropic diffusion, filtering 78 36
  • 4.63636
4.6 | 33 ratings
18 Mar 2003 DTMF Detector Detects DTMF tones in audio by Goertzel algorithm. Author: Frederico D'Almeida dtmf, communications, goertzel, audio, algorithm 13 1
21 Feb 2002 General Extra Toolbox Generic functions for matrix manipulation, image processing, etc. Author: Frederico D'Almeida fft, index, matrices, image manipulation, matrix, max 8 4
  • 2.5
2.5 | 4 ratings
18 Feb 2002 Shrink Eliminates image borders. Author: Frederico D'Almeida morphology, segmentation, shrink border image 6 0
18 Feb 2002 Posterize Reduces the number of colors of an image. Author: Frederico D'Almeida color, posterize reduce colo... 11 0

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