Local Adaptive Thresholding

Threshold with local statistics, such as mean or median.

Description

ADAPTIVETHRESHOLD An adaptive thresholding algorithm that seperates the foreground from the background with nonuniform illumination.
  bw=adaptivethreshold(IM,ws,C) outputs a binary image bw with the local threshold mean-C or median-C to the image IM.

ws is the local window size.

tm is 0 or 1, a switch between mean and median. tm=0 mean(default); tm=1 median.

Contributed by Guanglei Xiong ([e-mail]) at Tsinghua University, Beijing, China.

For more information, please see
  http://homepages.inf.ed.ac.uk/rbf/HIPR2/adpthrsh.htm

• Required Products: Image Processing Toolbox
• MATLAB release: MATLAB 7.0.4 (R14SP2)

[J. Zhou]

Pretty cool results with flexible options.
Great job!

[tester Mc tester]

it didnt work!!
i get
Error using ==> mat2gray
A must be double

[Alan Zhang]

The 2 lines near the end should be changed from:
sIM=mIM-IM;
bw=im2bw(sIM,C);
to:
sIM=mIM-IM-C;
bw=im2bw(sIM,0);
This change allows C to be +ve and negative. In the old code bw=im2bw(sIM,C) causes error when C is -ve.

[Piyorot Khongchuay]

cool

[saravanan kumar]

nice work

[amit vishnipolsky]

 

[mel tem]

thank you

[saravanan radhakrishnan]

really good code

[kayalvizhi lakshmanan]

 

[ranjeeth dasineni]

works great man!!

[zhang shi jie]

really nice

[alev soke]

thank you very much.
it is a perfect program.

[Guillermo Moreno]

Simple and Fast, thanks

[hafid rafi]

it's very very simple thanks

[sanjay bhattacharya]

Nice code, but not applicable in extreme situations.

[sanjay bhattacharya]

I have written a code without using any std functions like imfilter etc, its purely based on fundamentals.

CHECK OUT THE OUTPUT IMAGES
http://sites.google.com/site/adapthresh/

[sanjay bhattacharya]

it can detect the letters even where its very dark (see the lines in the end) line 8 etc

[Hans Müller]

@Sanjay

How about sharing it, then?

[Navneet Viswan]

is it possible to detect laser traces on an object using this algorithm?

[Martin]

 

[Jorge Lewinnek]

what is that window size?

[Ana Triana]

Easy to read and use. Thank you.

[Nektarios Valous]

Great script!

[eray]

Very simple and effective, thanks!

[Rosidah Lazid]

Had anyone here used this code for processing trabecular micro CT images? Appreciate your feedback on the outcome. Thanks.

[Shashi]

I did apply this algorithm on my images but it didn't work out completely. There is a research paper by Q.Huang et.al. which speaks about Otsu's thresholding using adaptive window. I would like to know if somebody has implemented that.

[Hokchhay Tann]

Great code, but not applicable to my type of images. I'm trying to make the threshold automated since I have a hundred thousands of this kind. I appreciate any suggestions.

https://sites.google.com/site/hokchhay10/