I use the package opencv2, and included "opencv/cv.h".  It reports a 
warning:
     #warning "This is a deprecated opencv header provided for 
compatibility. Please include a header from a corresponding opencv module"

I haven't been staying in this developing track.  It seems that cv.h is 
deprecated in Version 2 (or 2.1?).

What would be the right way then to include opencv headers?   -- It 
would be further appreciated if anyone can point me to the reason of 
that being deprecated.

Thanks!

Hao