Difference between revisions of "Adaptive Thresholding"
(→'''Global Value Adaptive Thresholding''': added section: Mixture Model Thresholding) |
(→'''Global Value Adaptive Thresholding''': added section: Other Types of Auto-Thresholding; found more info on Otsu thresholding) |
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* [http://zone.ni.com/devzone/conceptd.nsf/webmain/93BE563C89260D5E86256D8F0050B5E3 General Description] | * [http://zone.ni.com/devzone/conceptd.nsf/webmain/93BE563C89260D5E86256D8F0050B5E3 General Description] | ||
| − | === Otsu Thresholding === | + | === Otsu Auto-Thresholding === |
| + | A somewhat technical overview of the Otsu algorithm can be found in section 2 of [http://www.iis.sinica.edu.tw/JISE/2001/200109_01.pdf this paper]. The same paper additionally proposed a modified version of the Otsu algorithm that it asserts is less computationally expensive than the traditional Otsu algorithm. | ||
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| + | ==== Links ==== | ||
* [http://rsb.info.nih.gov/ij/plugins/otsu-thresholding.html Sample Image Filter] | * [http://rsb.info.nih.gov/ij/plugins/otsu-thresholding.html Sample Image Filter] | ||
** [http://rsb.info.nih.gov/ij/plugins/download/jars/Otsu_Thresholding.jar Original Source Code] | ** [http://rsb.info.nih.gov/ij/plugins/download/jars/Otsu_Thresholding.jar Original Source Code] | ||
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--[[User:DavidF|David]] 21:14, 7 Nov 2005 (EST) | --[[User:DavidF|David]] 21:14, 7 Nov 2005 (EST) | ||
| − | === Maximum Entropy Thresholding === | + | === Maximum Entropy Auto-Thresholding === |
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| + | ==== Links ==== | ||
* [http://rsb.info.nih.gov/ij/plugins/entropy.html Sample Image Filter] | * [http://rsb.info.nih.gov/ij/plugins/entropy.html Sample Image Filter] | ||
** [http://rsb.info.nih.gov/ij/plugins/download/Entropy_Threshold.java Original Source Code] | ** [http://rsb.info.nih.gov/ij/plugins/download/Entropy_Threshold.java Original Source Code] | ||
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--[[User:DavidF|David]] 21:27, 7 Nov 2005 (EST) | --[[User:DavidF|David]] 21:27, 7 Nov 2005 (EST) | ||
| − | === Mixture Model Thresholding === | + | === Mixture Model Auto-Thresholding === |
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| + | ==== Links ==== | ||
* [http://rsb.info.nih.gov/ij/plugins/mixture-modeling.html Sample Image Filter] | * [http://rsb.info.nih.gov/ij/plugins/mixture-modeling.html Sample Image Filter] | ||
** [http://rsb.info.nih.gov/ij/plugins/download/jars/Mixture_Modeling.jar Original Source Code] | ** [http://rsb.info.nih.gov/ij/plugins/download/jars/Mixture_Modeling.jar Original Source Code] | ||
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| + | === Other Types of Auto-Thresholding === | ||
| + | * Binary Clustering | ||
| + | * Metric | ||
| + | * Moments | ||
| + | ** "Moment preserving thresholding is a parametric method which segments the image based on the condition that the thresholded image has the same moments as the original image." - taken from [http://www.iis.sinica.edu.tw/JISE/2001/200109_01.pdf] | ||
| + | * Inner-class Variance | ||
== '''Local Value Adaptive Thresholding''' == | == '''Local Value Adaptive Thresholding''' == | ||
Revision as of 22:53, 7 November 2005
Adaptive thresholding is an image segmentation algorithm that appears quite resistent to varying lighting conditions.
Contents
Global Value Adaptive Thresholding
(useful for barrel-in-sunlight detection)
Otsu Auto-Thresholding
A somewhat technical overview of the Otsu algorithm can be found in section 2 of this paper. The same paper additionally proposed a modified version of the Otsu algorithm that it asserts is less computationally expensive than the traditional Otsu algorithm. -class variance with an exhaustive search." -
Links
I've been trying to analyze the source code of this image filter (not written by me) in order to figure out how the Otsu Thresholding algorithm works. I've had limited success, in that I have completely figured out how GrayLevelClass.java works. However I have not been able to decode OtsuThresholding.java which appears to contain the essential details specific to the Otsu algorithm. --David 21:14, 7 Nov 2005 (EST)
Maximum Entropy Auto-Thresholding
- taken from [1]
Links
Once again, I've tried to analyze the source code of this image filter in order to figure how the algorithm its using works. --David 21:27, 7 Nov 2005 (EST)
Mixture Model Auto-Thresholding
Links
Other Types of Auto-Thresholding
- Binary Clustering
- Metric
- Moments
- "Moment preserving thresholding is a parametric method which segments the image based on the condition that the thresholded image has the same moments as the original image." - taken from [2]
- Inner-class Variance
Local Value Adaptive Thresholding
(useful for line-on-grass detection)
