is there a version of Principle Component Analysis for images?
显示 更早的评论
hello everybody, i want to ask about Principle Component Analysis, a tool used for data analysis
is there a version for PCA that is used for analysis the images?
and i want a source code and some examples for that
thanks for your help
回答（3 个）
Sean de Wolski
2013-4-15
doc pca
and
edit pca
10 个评论
Adam Filion
2013-4-15
And regular pca, which I forgot about...
Mohamed Moawed
2013-4-15
Sean de Wolski
2013-4-15
What version are you using? If you are on a relatively old version, use princomp() as Adam suggested.
doc princomp
Or upgrade to the newest release:
Mohamed Moawed
2013-4-15
Sean de Wolski
2013-4-15
Turn the images into column vectors. Spatial location does not matter.
Mohamed Moawed
2013-4-15
Sean de Wolski
2013-4-15
x = I(:)
where I is your image.
Mohamed Moawed
2013-4-15
Sean de Wolski
2013-4-15
Essentially. You need to horizontally concatenate all of your images first.
Mohamed Moawed
2013-4-15
Adam Filion
2013-4-15
0 个投票
I don't know much PCA myself, but I know we have some built-in tools in Statistics and Wavelet toolboxes that may be of use:
http://www.mathworks.com/help/stats/princomp.html http://www.mathworks.com/help/wavelet/ug/multiscale-principal-components-analysis.html
There are also a number of entries on the File Exchange for PCA:
Image Analyst
2013-4-15
0 个投票
The most famous application of PCA to images is eigenfaces: http://en.wikipedia.org/wiki/Eigenface You can essentially construct any face image by a weighted sum of eigenface (PCA) images.
3 个评论
Mohamed Moawed
2013-4-15
Image Analyst
2013-4-16
Sure, you could do it. Would that be useful to you? Why do you want PCA component images anyway?
Mohamed Moawed
2013-4-16
类别
在 帮助中心 和 File Exchange 中查找有关 Dimensionality Reduction and Feature Extraction 的更多信息
2013-4-15
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
