Human Body Gait Analysis

I am trying to get the body points of human body such as wrist joint, ankle joint, hip joint etc. For that first I am thinking to get outline of human body in the image. But if I use Edge detection, it gives the detection of clothing including other objects in the image(as coming out in the image attached). So how to detect human in image and get the outline i.e. Silhouette of the the human body only without the outline of clothing. And once I get the outline of human body, then I can take the outer curve little inside to get the joints. Actually my final aim is get human body joints. If there are any alternative methods for obtaining it, then that would be helpful.