Get video from dvr card in c#

Question

hi
i have a samsung camera and a RoxRon dvr card, i can see the video in the dvr software but i can't connect to the dvr from my code in visual studio

please help me

when i use cvcreatecapture and so on, i get the error : Error: Unable to create capture from camera-1

i'm confused! whether i must use directx? or emgu is enough? or what?

please help me to get video from dvr or camera to a vision project(image processing)
thanks