Rank: 74 based on 485 downloads (last 30 days) and 12 files submitted
photo

Theodoros Giannakopoulos

E-mail
Company/University
Computational Intelligence Lab @ Demokritos . gr
Lat/Long
37.96795272827148, 23.76673698425293

Personal Profile:

Theodoros Giannakopoulos received his diploma of Informatics and Telecommunications in the University of Athens (2002), M.Sc. of SIPS ("Signal and Image Processing Systems), organised by University of Patras (2004) and his PhD in the field of audio analysis (University of Athens, 2009).

He is currently a research associate in
- Computational Intelligence Laboratory (CIL) of the Institute of Informatics and Telecommunications (National Center for Scientific Research "DEMOKRITOS", Greece)
- the Dpt of Informatics and Telecommunications in the University of Athens .

WEB PAGE: http://www.di.uoa.gr/~tyiannak

Professional Interests:
Signal Processing, Pattern recognition, audio classification, content-based multimedia indexing.

 

Watch this Author's files

 

Files Posted by Theodoros View all
  • 1 - 5 of
  • 12
Updated   File Tags Downloads
(last 30 days) 		Comments Rating
12 Sep 2012 Screenshot Image Processing GUI A simple GUI with basic image processing functionalities. Author: Theodoros Giannakopoulos image processing, gui, color filtering, moion filtering 98 5
  • 4.0
4.0 | 1 rating
24 Sep 2010 Screenshot Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos audio, speech, speech analysis, signal processing 79 6
  • 5.0
5.0 | 4 ratings
24 Feb 2009 Screenshot Generate report of .m files in html table Generates a report of the m-files in a given directory. Results are stored in an html file. Author: Theodoros Giannakopoulos matlab documentation, misc, help 2 2
  • 4.0
4.0 | 1 rating
08 Nov 2008 Screenshot Image retrieval - Query by Example Demo This demo provides a simple query by image example method, based on HSV values. Author: Theodoros Giannakopoulos color, image analysis, image retrieval, query by example 73 33
  • 4.2
4.2 | 16 ratings
20 May 2008 Screenshot Generate Animated GIF Files for Plotting Audio Data This m-file generates a animated GIF file that visualizes audio data. Author: Theodoros Giannakopoulos audio processing, video processing, audio visulization, animated gif, audio data, signal processing 10 1
  • 5.0
5.0 | 1 rating
Comments and Ratings by Theodoros View all
  • 1 - 5 of
  • 10
Updated File Comments Rating
19 Apr 2013 mmread Read virtually any media file in Windows, Linux, or Mac. Author: Micah Richert

Really nice work! Though, I have the following problem. When reading frames from a large video file and the function seems to be rather slow for large frame indeces. E.g
video = mmread('/home/tyiannak/Desktop/05-10-19.avi', [10000]);
runs for several seconds. I suppose this is due to some type of file seeking. Can I avoide this?
Regards,
Theodore
14 Mar 2013 Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos

Dear Nikolay. First of all thank you for your comments. Some notes on them:
(a) mp3 IO was not supported in older Matlab versions. Furthermore, audioread seems to have some OS compatibility issues, so I stuck with WAV file format only. Personally, I prefer to use some extrernal script for transcoding (e.g. commandline ffmpeg...)
(b) optioned listening seems right to me to: I will change this in the future
(c) GUI is also some fututre plan
(d) It's true that the precision / recall is not 100%: this is due to the very simple audio features adopted. One can rely to more sophisticated features for better results (e.g. mfccs, other spectral features etc).
I'd be glad to see your new results using and expanding this algorithm.
Again, thank you for your comments!
Theodoore
24 Mar 2011 mmread Read virtually any media file in Windows, Linux, or Mac. Author: Micah Richert

I've just downloaded your code and used it for reading mpeg files in Matlab. The fact that is worked without any problems on Ubuntu is really good, so ... thank you!
15 Feb 2011 Image Processing GUI A simple GUI with basic image processing functionalities. Author: Theodoros Giannakopoulos

Hi Sam. Thank you for your question. This is quite simple actually. You only need to add a button and then use the imrotate function (http://www.mathworks.com/help/toolbox/images/ref/imrotate.html). I am uploading an updated version which provides you the ability to rotate an image (rotate angle is selected in the range 0.360 using a slider).

03 Feb 2011 Image retrieval - Query by Example Demo This demo provides a simple query by image example method, based on HSV values. Author: Theodoros Giannakopoulos

Hi MUKUND SARDA, thank you for your interest. There is a quite detailed description of the algorithm above. In general the idea is quite simple: an empirical measure is defined on the thresholded distances of the HSV feature space. Then this similarity measure is sorted for returning the closest images. If you have any particular questions, please feel free to ask.
Comments and Ratings on Theodoros' Files View all
  • 1 - 5 of
  • 97
Updated File Comment by Comments Rating
02 Jul 2013 Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos Mojtaba

Ooops, it should be like this
output = [output; segments{i}];

02 Jul 2013 Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos Mojtaba

Thanks, It has very helpful comments and also works perfectly. It is also possible to add a few lines of code to concatenate the cell "segments" in order to have the removed silence version of the input signal, e.g.:

function [segments, fs, output] = detectVoiced(x, t)

output = [];
for i = length(segments)
output = [segments{i}; output];
end

29 May 2013 Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos muthu

how to run this coding give the steps and also i want use this code for my research work

22 May 2013 Color Detection Using HSV Color Space (Training and Testing) The provided Matlab functions demonstrate a simple method for training and testing a color detection Author: Theodoros Giannakopoulos zhengguo, dai

22 May 2013 Color Detection Using HSV Color Space (Training and Testing) The provided Matlab functions demonstrate a simple method for training and testing a color detection Author: Theodoros Giannakopoulos zhengguo, dai

my email is zhgdai@126.com
Top Tags Applied by Theodoros
  • 1 - 5 of
  • 48
audio processing, video processing, audio, color, image processing
Files Tagged by Theodoros View all
  • 1 - 5 of
  • 13
Updated   File Tags Downloads
(last 30 days) 		Comments Rating
12 Sep 2012 Screenshot Image Processing GUI A simple GUI with basic image processing functionalities. Author: Theodoros Giannakopoulos image processing, gui, color filtering, moion filtering 98 5
  • 4.0
4.0 | 1 rating
24 Sep 2010 Screenshot Silence removal in speech signals A simple method for silence removal in speech streams Author: Theodoros Giannakopoulos audio, speech, speech analysis, signal processing 79 6
  • 5.0
5.0 | 4 ratings
24 Feb 2009 Screenshot Generate report of .m files in html table Generates a report of the m-files in a given directory. Results are stored in an html file. Author: Theodoros Giannakopoulos matlab documentation, misc, help 2 2
  • 4.0
4.0 | 1 rating
08 Nov 2008 Screenshot Image retrieval - Query by Example Demo This demo provides a simple query by image example method, based on HSV values. Author: Theodoros Giannakopoulos color, image analysis, image retrieval, query by example 73 33
  • 4.2
4.2 | 16 ratings
20 May 2008 Screenshot Generate Animated GIF Files for Plotting Audio Data This m-file generates a animated GIF file that visualizes audio data. Author: Theodoros Giannakopoulos audio processing, video processing, audio visulization, animated gif, audio data, signal processing 10 1
  • 5.0
5.0 | 1 rating

Contact us