C++ :: Split Image To 3 Channels - Opencv Error

I am currently planning on splitting my image into 3 channels so i can get the RGB values of an image to plot a scatter graph so i can model is using a normal distribtion calculating the covariance matrix, mean, etc. then calculate distance between the background points and the actual image to segment the image.

Now in my first task, i have wrote the following code.

VideoCapture cam(0);
//int id=0;
Mat image, Rch,Gch,Bch;
vector<Mat> rgb(3); //RGB is a vector of 3 matrices
namedWindow("window");

[Code] ....

but as soon as it reaches the split function, i step through it, it causes a unhandled exception error. access violation writing location 0xfeeefeee.

I am still new to opencv, so am not used to dealing with unhandled exception error.

I tried adding items into the vector still error, either via push_back or general assignment i.e. rgb[0] = Rch or Bch still error.