title: How to undo a perspective transform for a single point in opencv
body: <p>I am trying to do some image analysis using an Inverse Perspective Map. I used the openCV functions getTransform and findHomography to generate a transformation matrix and apply it to the source image. This works well and I am able to get the points from the image I want. The problem is, I don't know how I can take individual point values and undo the transform to draw them back on the original picture. I want to only undo the transform for this set of points to find their original location. How does one do this. 
  The points are in the form Point(x,y) from the openCV library. </p>