Here is the code :
Mat _orange = imread("orange.jpg");
Mat_<Vec3f> orange;
_orange.convertTo(orange, orange.type(), 1.0/255.0);
The _orange.convertTo(orange, orange.type(), 1.0/255.0);
part causes the error.
Here is the error message:
OpenCV Error: Assertion failed (!fixedType() || ((Mat*)obj)->type() == mtype) in unknown function.
PS: I am using Visual Studio 2012 and OpenCV 2.4.4