The definition of covariance is
Cov(x, y) = E[ (X-E(X)) * (Y-E[Y]) ]
where E is abbreviation of expectation. It is same with Mean.
X = [1 2 3 4 5];
E(X) -> 3 or 3.75
3 is the result of "sum(X)/5"
3.75 is the result of "sum(X)/(5-1)"
In the statistics, mean is divided by N-1 to avoid outlier data affection.
*Example of Covariance
X = [ 2 3 4 2 1 4]
Y = [ 2 4 2 1 6 8]
meanX = sum(X) / 6 -> 2.667
(X - meanX) -> [-0.6667 0.3333 1.3333 -0.6667 -1.6667 1.3333]
(X - meanX) * (X -meanX) -> [ 0.4444 0.1111 1.7778 0.4444 2.7778 1.7778]
cov(x, x) -> sum( ( (X - meanX) * (X -meanX) ) ) / (N-1)
cov of X, Y is like that
-> cov(x,x) cov(x,y)
-> 1.4667 0.5333
in the matlab...
Image size of origin is 320*240. Processing time is 30.96 second took. The result of stitching The resul...
(OpenCV Study) Background subtractor MOG, MOG2, GMG example source code (BackgroundSubtractorMOG, BackgroundSubtractorMOG2, BackgroundSubtractorGMG)Background subtractor example souce code. OpenCV support about 3 types subtraction algorithm. Those are MOG, MOG2, GMG algorithms. Det...
As you can see in the following video, I created a class that stitching n cameras in real time. https://www.youtube.com/user/feelmare/sear...
The MNIST dataset is a dataset of handwritten digits, comprising 60 000 training examples and 10 000 test examples. The dataset can be downl...
Example source code of extract HOG feature from images, save descriptor values to xml file, using opencv (using HOGDescriptor )This example source code is to extract HOG feature from images. And save descriptors to XML file. The source code explain how to use HOGD...
I use MOG2 algorithm to background subtraction. The process is resize to small for more fast processing to blur for avoid noise affectio...
* Introduction - The solution shows panorama image from multi images. The panorama images is processing by real-time stitching algorithm...
This is example for background subtraction on opencv 3.2 version previously, I post 2.7 version example on here. http://study.marearts.co...
OpenCV Drawing Example, (line, circle, rectangle, ellipse, polyline, fillConvexPoly, putText, drawContours)line, circle, rectangle, ellipse, polyline, fillConvexPoly, putText, drawContours example source code!!. ... //http://study....
This post is about how to copy Mat data to vector and copy vector data to Mat. Reference this example source code. printf("///////...