Rank: 909 based on 84 downloads (last 30 days) and 2 files submitted
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Alceu Costa

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Company/University
University of Sao Paulo

Personal Profile:

http://www.icmc.usp.br/~alceufc Alceu Costa - ICMC/USP

Professional Interests:
Image Processing, Computer Vision, Machine Learning, CBIR, Computer Aided Diagnosis

 

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28 May 2013 SFTA Texture Extractor Implementation of the SFTA algorithm for texture feature extraction. Author: Alceu Costa image descriptors, image processing, computer vision, fractal, texture, texture descriptor 58 2
  • 4.0
4.0 | 1 rating
08 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa image processing, computer vision, fractal, image descriptors, box counting to bound... 26 5
  • 3.0
3.0 | 1 rating
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07 Nov 2012 SFTA Texture Extractor Implementation of the SFTA algorithm for texture feature extraction. Author: Alceu Costa

Hello Kaveh,

Thanks for the feedback. The extraction time of 24s that you are getting is considerably higher than the extraction times that I got in my experiments.

Just for comparison, I have just executed with a 720x576 grayscale image, setting the nt parameter to 8 and the extraction time was 6s:

>> tic; sfta(I, 8); toc;
Elapsed time is 6.039394 seconds.

Which value for the nt parameter that you are using? For the datasets that I have employed to test SFTA, I found that a value of nt higher than 8 did not increase classification accuracy.

Here’s a link to the article that I hope can help you:

http://www2.icmc.usp.br/~alceufc/documents/sibgrapi_afc_2012.pdf

23 Feb 2011 DIRR (find files recursively filtering name, date or bytes) Lists files recursively filtering name date and/or size. Output can be set as name date and/or size. Author: Maximilien Chaumon

18 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa

@Damodara

Just repeat the same procedure for each set of boundary point returned by bwboundaries.

If you have the original black and white image from which you extracted the boundary points, then you probably can use the bwperim function instead of bwboundaries.

10 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa

@Damodara

All you have to do is to convert the boundary points to a black and white image, where the non zero pixels are the boundary and the zero pixels are background.

First, get the linear indices of the boundary pixels:

>> B = bwboundaries(I);
>> BP = B{1}
>> L = sub2ind(size(Ib), BP(:,1), BP(:,2)) % Get the linear indices of the boundary pixels.

Then use the linear indices to generate the binary image Ib:

>> Ib = zeros(size(I))
>> Ib(L) = 1;

And then use Ib to compute the fractal dimension:

>> hausDim(Ib)

Comments and Ratings on Alceu's Files View all
Updated File Comment by Comments Rating
07 Nov 2012 SFTA Texture Extractor Implementation of the SFTA algorithm for texture feature extraction. Author: Alceu Costa Costa, Alceu

Hello Kaveh,

Thanks for the feedback. The extraction time of 24s that you are getting is considerably higher than the extraction times that I got in my experiments.

Just for comparison, I have just executed with a 720x576 grayscale image, setting the nt parameter to 8 and the extraction time was 6s:

>> tic; sfta(I, 8); toc;
Elapsed time is 6.039394 seconds.

Which value for the nt parameter that you are using? For the datasets that I have employed to test SFTA, I found that a value of nt higher than 8 did not increase classification accuracy.

Here’s a link to the article that I hope can help you:

http://www2.icmc.usp.br/~alceufc/documents/sibgrapi_afc_2012.pdf

04 Nov 2012 SFTA Texture Extractor Implementation of the SFTA algorithm for texture feature extraction. Author: Alceu Costa Mollazade, Kaveh

Dear Alceu,

Thank you. This is a nice method to compute the hausdorff's fractal dimension from the border of an object.
I have implemented your method on a data set.
It seems your method is computationally time consuming since for a 720*576 gray scale image, 24.453 second is required for analysis.
Have you any comments about this?

Regards,

Kaveh

28 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa Damodara

ya i got it ...!

18 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa Costa, Alceu

@Damodara

Just repeat the same procedure for each set of boundary point returned by bwboundaries.

If you have the original black and white image from which you extracted the boundary points, then you probably can use the bwperim function instead of bwboundaries.

17 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa Damodara

hi ,
if i have number of objects then how do i convert all those objects boundary.. in a single image.

Top Tags Applied by Alceu
computer vision, fractal, image descriptors, image processing, feature vector
Files Tagged by Alceu View all
Updated   File Tags Downloads
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28 May 2013 SFTA Texture Extractor Implementation of the SFTA algorithm for texture feature extraction. Author: Alceu Costa image descriptors, image processing, computer vision, fractal, texture, texture descriptor 58 2
  • 4.0
4.0 | 1 rating
08 Feb 2011 Hausdorff (Box-Counting) Fractal Dimension Returns the Haussdorf fractal dimension of an object represented by a binary image. Author: Alceu Costa image processing, computer vision, fractal, image descriptors, box counting to bound... 26 5
  • 3.0
3.0 | 1 rating

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