title: How to draw the trajectory ( tracking path ) of an moving object in an image - Opencv?
body: <p>How to draw the trajectory ( tracking path ) in an image - Opencv ?</p>
  
  <p>i know the co-ordinates of an moving object ( x,y), every frame it is updating new (x ,y ) co-ordinates.</p>
  
  <p>now How to draw the trajectory  path of an object for last 20 frames or N number of frames.</p>